HYDROLOGIC/HYDRAULIC ANALYSIS REPORT FOR THE TROLLEY BROOK CULVERT ASHLAND, MA

Transcription

1 HYDROLOGIC/HYDRAULIC ANALYSIS REPORT FOR THE TROLLEY BROOK CULVERT ASHLAND, MA Prepared for: THE TOWN OF ASHLAND BOARD OF SELECTMEN AND PLANNING DEPARTMENT Prepared by: June 3, 216

2 Hydrologic/Hydraulic Analysis Report Trolley Brook Culvert, Ashland, MA June 3, 216 TABLE OF CONTENTS SUBJECT PAGE PURPOSE 3 INTRODUCTION AND WATERSHED DESCRIPTION 3 METHODOLOGY 3 DATA AND ASSUMPTIONS 4 SUMMARY 6 CONCLUSION 7 RECOMMENDATIONS 7 8 APPENDICES A HydroCAD Report Existing Flows to Culvert B HydroCAD Report Proposed Flows to Culvert C Existing HydroCAD Report 1 Yr Storm with Node Summaries D Proposed HydroCAD Report 1 Yr Storm with Node Summaries E NRCS Soils Data F Rainfall Data Obtained from NOAA Atlas 14 G Trolley Brook Plan and Profiles H Observation Photos I Compiled Watershed Plan Note Photo on cover from: Google Earth Page 2 of 8

3 Hydrologic/Hydraulic Analysis Report Trolley Brook Culvert, Ashland, MA June 3, 216 PURPOSE The Town is concerned about the stormwater runoff impacts of the proposed Rail Transit District Apartments Project on the existing Trolley Brook Culvert. A hydrologic model was developed to analyzed the impacts. This report is provided to summarize the development of the model and summarize the analysis. INTRODUCTION AND WATERSHED DESCRIPTION The 193± feet long culvert conveys stream and stormwater runoff flow between Megunko Road and the railroad tracks through downtown and outlets at the Sudbury River behind the Town library. The project watershed area (316± acres) includes Lorraine Drive, portions of Pennock Road, Wilbur Drive and the Middle School to the South; the Rail Transit District Apartment site and High Street Bridge over the MBTA tracks to the west; the south side of Pleasant Street to the north; and the Library and west of the residences on Cherry Street to the East. Just over half the area (179± acres) is presently wooded, 37± acres are wetlands, 39± acres are fields (Nyanza landfill and Middle school athletic fields), 32± acres are residential areas, 37± acres of industrial/commercial sites with another 17± acres of roof/roads. Natural Resources Conservation Service (NRCS) mapping indicates that soils (47±%) within the watershed are predominately hydrologic group rating A soils, 16±% are C soils, 1±% are D soils, 21±% are unrated. The watershed area to the Trolley Brook Culvert is complex and sizable with stormwater runoff from 316± acres of land contributory to the inlet off Megunko Road. The culvert also serves to convey stormwater runoff from a section of the downtown area with drainage connections at each junction (drain manhole). Existing wetland areas, streams and culverts help capture, contain and control peak rates of runoff. The fire station has been flooded during previous large storm events. The Rail Transit District Apartments Project is proposed to develop 3± acres of woodland to construct 398 unit apartment complex with associated access drives, parking areas and utilities. Prior review of the calculations provided indicates that the peak rate of runoff will be maintained from the developed area; however, the volume of runoff will be increased which discharges to the north wetlands and thence to Chemical Brook to the culvert. METHODOLOGY The hydrologic analysis was complete using HydroCAD, a computer program that models the hydrology using the Urban Hydrology for Small Watersheds TR (SCS) method and routing and hydraulics using TR 2 methodology. The analysis was completed for a Type III 24 hour storm using Dynamic Storage Indication Method to account for tailwater. Page 3 of 8

4 Hydrologic/Hydraulic Analysis Report Trolley Brook Culvert, Ashland, MA June 3, 216 DATA AND ASSUMPTIONS The following data was compiled and assumptions were made to complete the analysis. Watershed plans were compiled and developed from the following sources: Town GIS provided by the Ashland Engineering Department Site Plan (1) entitled AS BUILT PLAN LORRAINE DRIVE dated August 1, 21, revised September 18, 21, Prepared by GLM Engineering Consultants, Inc., 17 Washington Street, Holliston, MA Site Plan (1) entitled Parking & Traffic Control Key Plan, Jefferson at Ashland Station Ashland Massachusetts, dated 2/2/22, revised 4/1/28, Prepared by Allen & Major Associates, Inc. Document entitled Stormwater Management Report, Ashland Rail Transit Apartments Ashland, MA dated 9/28/1, Prepared by Kelly Engineering Group, Inc. Site Plan (17) entitled Site Development Plans for Ashland Rail Transit Apartments M.B.T.A. Access Road Ashland, MA, dated September 28, 21, revised 3/7/216, Prepared by Kelly Engineering Group, Inc. Site Plan (24) entitled Access and Utility Easement Exhibit Plan of Land in Ashland, MA, dated 12//7, Prepared by Hancock Associates, 1 Centre Street, Danvers, MA 1923 Plans (2) Attachment A, entitled Existing Drainage Exhibit and Attachment B, entitled Proposed Drainage Exhibit dated 9/28/1, Prepared by Kelly Engineering Group, Inc. Google Earth and Google Maps Hydrologic soils data and group ratings obtained from Natural Resources Conservation Service Web Soil Survey ( o B/D and C/D soils were modeled as D soils assuming saturated conditions o Nyanza grass cap was assumed to be C soils o Udorthents were assumed as A soils due to classification of surrounding soils Note that previous calculations for the Rail Transit District Apartments Project, utilize a D rating for the Paxton soils on the project site where these calculations use the NRSC rating of C for these soils. Field survey of the culvert completed by Borderland Engineering, Inc. Field observations on April 19, May 11 & 24 and June 1, 7 & 8 Nyanza landfill drainage system plans were not available and PSC did not have access to the site for this report. MBTA Access Road plans and calculations were not available and subsurface infiltration system sizes could not be verified and therefore are not included in this analysis. Page 4 of 8

5 Hydrologic/Hydraulic Analysis Report Trolley Brook Culvert, Ashland, MA June 3, 216 Rainfall data obtained from NOAA Atlas 14, Volume 1, Version 2, 24 hour rainfall ( for the following events: 1 Yr = 2.73 in. 2 Yr. = 3.36 in. Yr. = 4.4 in. 1 Yr. =.2 in. 2 Yr. = 6.43 in. Yr. = 7.34 in. 1 Yr. = 8.2 in. Note that previous calculation for the culvert and the Rail Transit District Apartments project utilized TP 4 data which uses 6. inches of rainfall for a 1 year, 24 hour rainfall event (slightly more than the 2 year NOAA Atlas 14 storm event). 1 minute minimum time of concentration (Tc) was assumed for urbanized areas. Tail water (flood) elevations associated with the Charles River were not used assuming the peak elevations for the river will be hours later than the peak for this watershed. SUMMARY Analysis of the model concentrates on the impacts of the development on flooding of the culvert. Appendices C and D includes a complete HydroCAD report for the existing and proposed 1 year storm events with node summaries for the entire watershed for the 2,, 2, and 1 year storm events. However, the Town is primarily concerned about the impact of the development on the existing culvert through the downtown area summaries of which are outlined in the tables below. Backup data for these tables is provided in Appendices C and D. Although there is a large percentage of highly permeable soils and wetlands that absorb and store significant quantities of the stormwater runoff within the watershed, the culvert is unable to accommodate peak runoff from all storm events. The model indicates the culvert is surcharged under the 2 year storm event and is not able to accommodate the year storm. Due to the proposed project s distance from the culvert and that stormwater management measure are proposed to control the peak rate of runoff from the site Table 1 shows that the peak rate of runoff will not be measurably exceeded at the culvert until the year storm event. This is due to the increase of the second peak coinciding with runoff flows from the Middle School and Megunko Hill residential properties. Table 2 however shows a measurable increase in the volume of runoff reaching the culvert starting at the 2 year storm event and Table 3 shows the increase in flooding at the entrance to the culvert (flow that the culvert cannot accommodate). The substantial increase for the 1 year storm event is due, again, to the increase of the second peak runoff flows. The culvert is not allowed to catch up before incoming flow from the development area and upper reaches of the watershed area causes combined flows to again exceed the inlet capacity of the culvert. Page of 8

6 Hydrologic/Hydraulic Analysis Report Trolley Brook Culvert, Ashland, MA June 3, 216 TABLE 1 PEAK STORMWATER RUNOFF FLOWS TO ENTRANCE TO CULVERT Storm Event (Year) Rain (in) Existing Proposed Change % % % % % % 9% 1% Flows measured in cubic feet per second () TABLE 2 VOLUME OF STORMWATER RUNOFF FLOWS TO ENTRANCE TO CULVERT Storm Event (Year) Rain (in) Existing Proposed Change % % % 7% 7% 7% 6% 6% Volumes measured in acre feet (af) TABLE 3 VOLUME OF STORMWATER RUNOFF FLOODING AT ENTRANCE TO CULVERT Storm Existing Future Flooding Year Total Primary Secondary Total Primary Secondary af % % % % % % Primary is flow that is conveyed by the culvert Secondary is flow that cannot currently be accommodated by the culvert Page 6 of 8

7 Hydrologic/Hydraulic Analysis Report Trolley Brook Culvert, Ashland, MA June 3, 216 CONCLUSION The proposed Rail Transit District Apartments Project has raised the focus on flooding issues associated with the culvert system that conveys water from Trolley Brook through the downtown area. Concerns are highlighted by the following reports, data and observations. I. Properties (notably the Fire Station) along the culvert have experienced flooding during larger storm events. II. III. IV. Climate data indicates that larger storm events are occurring with greater frequency. Currently the head losses due to inlet blockage, sharp bends, reverse flow or flat pipes, differential vertical pipe alignment through structures, inefficient culvert materials, blockage from protruding pipe connections and tail water elevations reduce the flow capacity of the culvert. Hydrologic calculations for the Rail Transit District Apartments Project within the watershed indicate an increase in the volume of stormwater runoff that the culvert needs to accommodate. V. The culvert is currently surcharged during the 2 year storm event and its capacity is exceeded for the year storm event. VI. VII. The proposed development will increase in the peak rate of runoff for the and 1 year storm events. The additional volume of runoff from the proposed development will increase flooding of the culvert significantly for the 1 year and higher storms. RECOMMENDATIONS 1. In order to maintain the current (existing condition) frequency and severity of flooding, the stormwater management system for the Rail Transit District Apartments project would need to be revised so post development runoff volumes do not exceed existing runoff volumes. This would require additional best management practices (BMPs) and/or low impact development (LID) techniques to provide additional infiltration on site. 2. Interim maintenance items to maximize capacity of existing culvert. a. Install a self cleaning trash rack to replace bars at the inlet. b. Cut and remove pipe sections, where possible, that extend into the culvert. c. Locate and expose the two junctions that could not be located during field survey to observe the invert elevations, condition and potential capacity issues. d. Investigate the reason 18 inches of water was observed in DMH9 in Front Street. Page 7 of 8

8 Hydrologic/Hydraulic Analysis Report Trolley Brook Culvert, Ashland, MA June 3, For MassDOT projects, culverts of this significance are required to be sized to convey the 2 to year storm event. Each of the following options will require additional evaluation of land rights, construction issues, permitting, long term impacts, and costs. a. Option 1: Provide LID techniques and BMPs up gradient of the culvert to reduce and control runoff from the watershed. This requires utilizing limited upland (not within wetland resource) areas and outside the Nyanza cap and contamination area. b. Option 2: Replace the existing culvert with a 6 foot wide by 4 foot high box culvert or equivalent. This will increase flow downgradient of the culvert and possibly increase flooding frequency and severity and at a significant construction cost. c. Option 3: Provide a bypass capability within the watershed that would convey flow in excess of the existing capacity of the culvert to the Sudbury River. Land acquisition permitting and downgradient impacts will need to be evaluated. Page 8 of 8

9 HYDROLOGIC/HYDRAULIC ANALYSIS REPORT FOR THE TROLLEY BROOK CULVERT ASHLAND, MA APPENDIX A HydroCAD Report Existing Flows to Culvert

10 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=2.73" Printed 6/17/216 Page 1 Summary for Pond C: Inlet to Culvert [63] Warning: Exceeded Reach TB1 INLET depth by hrs Area = ac, 1.81% Impervious, Depth > 1.33" for 1 Year St event = hrs, Volume= 32. af = hrs, Volume= 32. af, Atten= %, Lag=. min Primary = hrs, Volume= 32. af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= 12.4 hrs Flood Elev= 191.2' Device Routing Invert Outlet Devices #1 Primary 187.' 36." Round Culvert L= 82.' RCP, sq.cut end projecting, Ke=. Inlet / Outlet Invert= 187.' / 186.4' S=.73 '/' Cc=.9 n=.12, Flow Area= 7.7 sf #2 Secondary 191.2' 2.' long x 1.' breadth Broad-Crested Rectangular Weir Head (feet) Coef. (English) Primary OutFlow hrs HW=189.49' TW=188.99' (Dynamic Tailwater) 1=Culvert (Outlet Controls 4.6 fps) Secondary OutFlow hrs HW=187.2' TW=.' (Dynamic Tailwater) 2=Broad-Crested Rectangular Weir ( Controls. ) Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=2.73" Printed 6/17/216 Page 2 Pond C: Inlet to Culvert Area=288.2 ac Peak Elev=189.' Primary Secondary

11 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=2.73" Printed 6/17/216 Page 3 for Pond C: Inlet to Culvert Time (hours) () Elevation (feet) () Primary Secondary () () Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=2.73" Printed 6/17/216 Page 4 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () ()

12 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=2.73" Printed 6/17/216 Page for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () () Trolley Brook Culvert - EXISTING Condition Type III 24-hr 2 Year St Rainfall=3.36" Printed 6/17/216 Page 6 Summary for Pond C: Inlet to Culvert [8] Hint: Peaked.' above defined flood level [63] Warning: Exceeded Reach TB1 INLET depth by hrs Area = ac, 1.81% Impervious, Depth > 1.46" for 2 Year St event = 12.4 hrs, Volume= af = 12.4 hrs, Volume= af, Atten= %, Lag=. min Primary = hrs, Volume= af Secondary hrs, Volume=.8 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 191.2' Device Routing Invert Outlet Devices #1 Primary 187.' 36." Round Culvert L= 82.' RCP, sq.cut end projecting, Ke=. Inlet / Outlet Invert= 187.' / 186.4' S=.73 '/' Cc=.9 n=.12, Flow Area= 7.7 sf #2 Secondary 191.2' 2.' long x 1.' breadth Broad-Crested Rectangular Weir Head (feet) Coef. (English) Primary OutFlow hrs HW=191.2' TW=19.6' (Dynamic Tailwater) 1=Culvert (Inlet Controls 3.88 fps) Secondary OutFlow hrs HW=191.2' TW=.' (Dynamic Tailwater) 2=Broad-Crested Rectangular Weir (Weir fps)

13 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 2 Year St Rainfall=3.36" Printed 6/17/216 Page 7 Pond C: Inlet to Culvert Primary Secondary Area=288.2 ac Peak Elev=191.2' Trolley Brook Culvert - EXISTING Condition Type III 24-hr 2 Year St Rainfall=3.36" Printed 6/17/216 Page 8 for Pond C: Inlet to Culvert Time (hours) () Elevation (feet) () Primary Secondary () ()

14 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 2 Year St Rainfall=3.36" Printed 6/17/216 Page 9 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () () Trolley Brook Culvert - EXISTING Condition Type III 24-hr 2 Year St Rainfall=3.36" Printed 6/17/216 Page 1 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () ()

15 Trolley Brook Culvert - EXISTING Condition Type III 24-hr Year St Rainfall=4.4" Printed 6/17/216 Page 11 Summary for Pond C: Inlet to Culvert [8] Hint: Peaked.66' above defined flood level [63] Warning: Exceeded Reach TB1 INLET depth by hrs Area = ac, 1.81% Impervious, Depth > 1.88" for Year St event = hrs, Volume= 4.4 af = hrs, Volume= 4.4 af, Atten= %, Lag=. min Primary = hrs, Volume= af Secondary = hrs, Volume=.82 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 191.2' Device Routing Invert Outlet Devices #1 Primary 187.' 36." Round Culvert L= 82.' RCP, sq.cut end projecting, Ke=. Inlet / Outlet Invert= 187.' / 186.4' S=.73 '/' Cc=.9 n=.12, Flow Area= 7.7 sf #2 Secondary 191.2' 2.' long x 1.' breadth Broad-Crested Rectangular Weir Head (feet) Coef. (English) Primary OutFlow hrs HW=191.46' TW=191.19' (Dynamic Tailwater) 1=Culvert (Inlet Controls 2.1 fps) Secondary OutFlow hrs HW=191.8' TW=.' (Dynamic Tailwater) 2=Broad-Crested Rectangular Weir (Weir Controls 2.23 fps) Trolley Brook Culvert - EXISTING Condition Type III 24-hr Year St Rainfall=4.4" Printed 6/17/216 Page 12 Pond C: Inlet to Culvert Area=288.2 ac Peak Elev=191.86' Primary Secondary

16 Trolley Brook Culvert - EXISTING Condition Type III 24-hr Year St Rainfall=4.4" Printed 6/17/216 Page 13 for Pond C: Inlet to Culvert Time (hours) () Elevation (feet) () Primary Secondary () () Trolley Brook Culvert - EXISTING Condition Type III 24-hr Year St Rainfall=4.4" Printed 6/17/216 Page 14 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () ()

17 Trolley Brook Culvert - EXISTING Condition Type III 24-hr Year St Rainfall=4.4" Printed 6/17/216 Page 14 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () () Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 16 Summary for Pond C: Inlet to Culvert [8] Hint: Peaked.81' above defined flood level [61] Hint: Exceeded Reach CB1 outlet invert hrs [63] Warning: Exceeded Reach TB1 INLET depth by hrs Area = ac, 1.81% Impervious, Depth > 2.3" for 1 Year St event hrs, Volume=.188 af hrs, Volume=.188 af, Atten= %, Lag=. min Primary = hrs, Volume= af Secondary = hrs, Volume= 2.41 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 191.2' Device Routing Invert Outlet Devices #1 Primary 187.' 36." Round Culvert L= 82.' RCP, sq.cut end projecting, Ke=. Inlet / Outlet Invert= 187.' / 186.4' S=.73 '/' Cc=.9 n=.12, Flow Area= 7.7 sf #2 Secondary 191.2' 2.' long x 1.' breadth Broad-Crested Rectangular Weir Head (feet) Coef. (English) Primary OutFlow hrs HW=191.67' TW=191.4' (Dynamic Tailwater) 1=Culvert (Inlet Controls 2.2 fps) Secondary OutFlow hrs HW=192.1' TW=.' (Dynamic Tailwater) 2=Broad-Crested Rectangular Weir (Weir Controls 2.6 fps)

18 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 17 Pond C: Inlet to Culvert Area=288.2 ac Peak Elev=192.1' Primary Secondary Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 18 for Pond C: Inlet to Culvert Time (hours) () Elevation (feet) () Primary Secondary () ()

19 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 19 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () () Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 2 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () ()

20 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 2 Year St Rainfall=6.43" Printed 6/17/216 Page 21 Summary for Pond C: Inlet to Culvert [8] Hint: Peaked.9' above defined flood level [61] Hint: Exceeded Reach CB1 outlet invert hrs [63] Warning: Exceeded Reach TB1 INLET depth by hrs Area = ac, 1.81% Impervious, Depth > 2.97" for 2 Year St event = 12.4 hrs, Volume= af = 12.4 hrs, Volume= af, Atten= %, Lag=. min Primary = hrs, Volume= af Secondary = hrs, Volume= af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 191.2' Device Routing Invert Outlet Devices #1 Primary 187.' 36." Round Culvert L= 82.' RCP, sq.cut end projecting, Ke=. Inlet / Outlet Invert= 187.' / 186.4' S=.73 '/' Cc=.9 n=.12, Flow Area= 7.7 sf #2 Secondary 191.2' 2.' long x 1.' breadth Broad-Crested Rectangular Weir Head (feet) Coef. (English) Primary OutFlow hrs HW=191.81' TW=191.14' (Dynamic Tailwater) 1=Culvert (Inlet Controls 3.94 fps) Secondary OutFlow hrs HW=192.13' TW=.' (Dynamic Tailwater) 2=Broad-Crested Rectangular Weir (Weir Controls 2.84 fps) Trolley Brook Culvert - EXISTING Condition Type III 24-hr 2 Year St Rainfall=6.43" Printed 6/17/216 Page 22 Pond C: Inlet to Culvert Primary Secondary Area=288.2 ac Peak Elev=192.1'

21 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 2 Year St Rainfall=6.43" Printed 6/17/216 Page 23 for Pond C: Inlet to Culvert Time (hours) () Elevation (feet) () Primary Secondary () () Trolley Brook Culvert - EXISTING Condition Type III 24-hr 2 Year St Rainfall=6.43" Printed 6/17/216 Page 24 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () ()

22 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 2 Year St Rainfall=6.43" Printed 6/17/216 Page 2 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () () Trolley Brook Culvert - EXISTING Condition Type III 24-hr Year St Rainfall=7.34" Printed 6/17/216 Page 26 Summary for Pond C: Inlet to Culvert [8] Hint: Peaked 1.4' above defined flood level [61] Hint: Exceeded Reach CB1 outlet invert 12.4 hrs [63] Warning: Exceeded Reach TB1 INLET depth by hrs Area = ac, 1.81% Impervious, Depth > 3.3" for Year St event = hrs, Volume= af = hrs, Volume= af, Atten= %, Lag=. min Primary = 12.4 hrs, Volume= af Secondary = 12.4 hrs, Volume= af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= 12.4 hrs Flood Elev= 191.2' Device Routing Invert Outlet Devices #1 Primary 187.' 36." Round Culvert L= 82.' RCP, sq.cut end projecting, Ke=. Inlet / Outlet Invert= 187.' / 186.4' S=.73 '/' Cc=.9 n=.12, Flow Area= 7.7 sf #2 Secondary 191.2' 2.' long x 1.' breadth Broad-Crested Rectangular Weir Head (feet) Coef. (English) Primary OutFlow 12.4 hrs HW=191.89' TW=191.73' (Dynamic Tailwater) 1=Culvert (Inlet Controls 1.91 fps) Secondary OutFlow 12.4 hrs HW=192.22' TW=.' (Dynamic Tailwater) 2=Broad-Crested Rectangular Weir (Weir Controls 3.2 fps)

23 Trolley Brook Culvert - EXISTING Condition Type III 24-hr Year St Rainfall=7.34" Printed 6/17/216 Page 27 Pond C: Inlet to Culvert Area=288.2 ac Peak Elev=192.24' Primary Secondary Trolley Brook Culvert - EXISTING Condition Type III 24-hr Year St Rainfall=7.34" Printed 6/17/216 Page 28 for Pond C: Inlet to Culvert Time (hours) () Elevation (feet) () Primary Secondary () ()

24 Trolley Brook Culvert - EXISTING Condition Type III 24-hr Year St Rainfall=7.34" Printed 6/17/216 Page 29 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () () Trolley Brook Culvert - EXISTING Condition Type III 24-hr Year St Rainfall=7.34" Printed 6/17/216 Page 3 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () ()

25 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=8.2" Printed 6/17/216 Page 31 Summary for Pond C: Inlet to Culvert [8] Hint: Peaked 1.8' above defined flood level [61] Hint: Exceeded Reach CB1 outlet invert hrs [63] Warning: Exceeded Reach TB1 INLET depth by hrs Area = ac, 1.81% Impervious, Depth > 4.13" for 1 Year St event = hrs, Volume= af = hrs, Volume= af, Atten= %, Lag=. min Primary = hrs, Volume= af Secondary = hrs, Volume= af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 191.2' Device Routing Invert Outlet Devices #1 Primary 187.' 36." Round Culvert L= 82.' RCP, sq.cut end projecting, Ke=. Inlet / Outlet Invert= 187.' / 186.4' S=.73 '/' Cc=.9 n=.12, Flow Area= 7.7 sf #2 Secondary 191.2' 2.' long x 1.' breadth Broad-Crested Rectangular Weir Head (feet) Coef. (English) Primary OutFlow hrs HW=191.99' TW=191.7' (Dynamic Tailwater) 1=Culvert (Inlet Controls 2.37 fps) Secondary OutFlow hrs HW=192.27' TW=.' (Dynamic Tailwater) 2=Broad-Crested Rectangular Weir (Weir Controls 3.11 fps) Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=8.2" Printed 6/17/216 Page 32 Pond C: Inlet to Culvert Area=288.2 ac Peak Elev=192.28' Primary Secondary

26 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=8.2" Printed 6/17/216 Page 33 for Pond C: Inlet to Culvert Time (hours) () Elevation (feet) () Primary Secondary () () Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=8.2" Printed 6/17/216 Page 34 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () ()

27 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=8.2" Printed 6/17/216 Page 3 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () () Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=8.2" Printed 6/17/216 Page 36 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () ()

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29 HYDROLOGIC/HYDRAULIC ANALYSIS REPORT FOR THE TROLLEY BROOK CULVERT ASHLAND, MA APPENDIX B HydroCAD Report Proposed Flows to Culvert

30 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=2.73" Printed 6/17/216 Page 1 Summary for Pond C: Inlet to Culvert [63] Warning: Exceeded Reach TB1 INLET depth by hrs Area = 294. ac, 19.89% Impervious, Depth > 1.31" for 1 Year St event = hrs, Volume= af = hrs, Volume= af, Atten= %, Lag=. min Primary = hrs, Volume= af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= 12.4 hrs Flood Elev= 191.2' Device Routing Invert Outlet Devices #1 Primary 187.' 36." Round Culvert L= 82.' RCP, sq.cut end projecting, Ke=. Inlet / Outlet Invert= 187.' / 186.4' S=.73 '/' Cc=.9 n=.12, Flow Area= 7.7 sf #2 Secondary 191.2' 2.' long x 1.' breadth Broad-Crested Rectangular Weir Head (feet) Coef. (English) Primary OutFlow hrs HW=189.49' TW=188.99' (Dynamic Tailwater) 1=Culvert (Outlet Controls 4.6 fps) Secondary OutFlow hrs HW=187.2' TW=.' (Dynamic Tailwater) 2=Broad-Crested Rectangular Weir ( Controls. ) Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=2.73" Printed 6/17/216 Page 2 Pond C: Inlet to Culvert Area=294. ac Peak Elev=189.' Primary Secondary

31 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=2.73" Printed 6/17/216 Page 3 for Pond C: Inlet to Culvert Time (hours) () Elevation (feet) () Primary Secondary () () Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=2.73" Printed 6/17/216 Page 4 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () ()

32 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=2.73" Printed 6/17/216 Page for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () () Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 2 Year St Rainfall=3.36" Printed 6/17/216 Page 6 Summary for Pond C: Inlet to Culvert [8] Hint: Peaked.' above defined flood level [63] Warning: Exceeded Reach TB1 INLET depth by hrs Area = 294. ac, 19.89% Impervious, Depth > 1.1" for 2 Year St event = 12.4 hrs, Volume= 37.7 af = 12.4 hrs, Volume= 37.7 af, Atten= %, Lag=. min Primary = 12. hrs, Volume= af Secondary hrs, Volume=.8 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 191.2' Device Routing Invert Outlet Devices #1 Primary 187.' 36." Round Culvert L= 82.' RCP, sq.cut end projecting, Ke=. Inlet / Outlet Invert= 187.' / 186.4' S=.73 '/' Cc=.9 n=.12, Flow Area= 7.7 sf #2 Secondary 191.2' 2.' long x 1.' breadth Broad-Crested Rectangular Weir Head (feet) Coef. (English) Primary OutFlow 12. hrs HW=191.2' TW=19.' (Dynamic Tailwater) 1=Culvert (Inlet Controls 3.88 fps) Secondary OutFlow hrs HW=191.2' TW=.' (Dynamic Tailwater) 2=Broad-Crested Rectangular Weir (Weir fps)

33 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 2 Year St Rainfall=3.36" Printed 6/17/216 Page 7 Pond C: Inlet to Culvert Primary Secondary Area=294. ac Peak Elev=191.2' Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 2 Year St Rainfall=3.36" Printed 6/17/216 Page 8 for Pond C: Inlet to Culvert Time (hours) () Elevation (feet) () Primary Secondary () ()

34 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 2 Year St Rainfall=3.36" Printed 6/17/216 Page 9 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () () Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 2 Year St Rainfall=3.36" Printed 6/17/216 Page 1 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () ()

35 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr Year St Rainfall=4.4" Printed 6/17/216 Page 11 Summary for Pond C: Inlet to Culvert [8] Hint: Peaked.68' above defined flood level [63] Warning: Exceeded Reach TB1 INLET depth by hrs Area = 294. ac, 19.89% Impervious, Depth > 1.96" for Year St event = 12.4 hrs, Volume= af = 12.4 hrs, Volume= af, Atten= %, Lag=. min Primary = hrs, Volume= af Secondary = hrs, Volume=.832 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 191.2' Device Routing Invert Outlet Devices #1 Primary 187.' 36." Round Culvert L= 82.' RCP, sq.cut end projecting, Ke=. Inlet / Outlet Invert= 187.' / 186.4' S=.73 '/' Cc=.9 n=.12, Flow Area= 7.7 sf #2 Secondary 191.2' 2.' long x 1.' breadth Broad-Crested Rectangular Weir Head (feet) Coef. (English) Primary OutFlow hrs HW=191.39' TW=19.66' (Dynamic Tailwater) 1=Culvert (Inlet Controls 4.13 fps) Secondary OutFlow hrs HW=191.88' TW=.' (Dynamic Tailwater) 2=Broad-Crested Rectangular Weir (Weir Controls 2.3 fps) Trolley Brook Culvert - PROPOSED Condition Type III 24-hr Year St Rainfall=4.4" Printed 6/17/216 Page 12 Pond C: Inlet to Culvert Area=294. ac Peak Elev=191.88' Primary Secondary

36 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr Year St Rainfall=4.4" Printed 6/17/216 Page 13 for Pond C: Inlet to Culvert Time (hours) () Elevation (feet) () Primary Secondary () () Trolley Brook Culvert - PROPOSED Condition Type III 24-hr Year St Rainfall=4.4" Printed 6/17/216 Page 14 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () ()

37 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr Year St Rainfall=4.4" Printed 6/17/216 Page 1 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () () Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 16 Summary for Pond C: Inlet to Culvert [8] Hint: Peaked.83' above defined flood level [61] Hint: Exceeded Reach CB1 outlet invert 12.3 hrs [63] Warning: Exceeded Reach TB1 INLET depth by 12.3 hrs Area = 294. ac, 19.89% Impervious, Depth > 2.41" for 1 Year St event hrs, Volume= 8.93 af hrs, Volume= 8.93 af, Atten= %, Lag=. min Primary = hrs, Volume= 3.41 af Secondary = 12.3 hrs, Volume=.466 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= 12.3 hrs Flood Elev= 191.2' Device Routing Invert Outlet Devices #1 Primary 187.' 36." Round Culvert L= 82.' RCP, sq.cut end projecting, Ke=. Inlet / Outlet Invert= 187.' / 186.4' S=.73 '/' Cc=.9 n=.12, Flow Area= 7.7 sf #2 Secondary 191.2' 2.' long x 1.' breadth Broad-Crested Rectangular Weir Head (feet) Coef. (English) Primary OutFlow hrs HW=191.66' TW=191.29' (Dynamic Tailwater) 1=Culvert (Inlet Controls 2.92 fps) Secondary OutFlow 12.3 hrs HW=192.' TW=.' (Dynamic Tailwater) 2=Broad-Crested Rectangular Weir (Weir 2.4 fps)

38 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 17 Pond C: Inlet to Culvert Area=294. ac Peak Elev=192.3' Primary Secondary Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 18 for Pond C: Inlet to Culvert Time (hours) () Elevation (feet) () Primary Secondary () ()

39 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 19 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () () Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 2 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () ()

40 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 2 Year St Rainfall=6.43" Printed 6/17/216 Page 21 Summary for Pond C: Inlet to Culvert [8] Hint: Peaked.94' above defined flood level [61] Hint: Exceeded Reach CB1 outlet invert hrs [63] Warning: Exceeded Reach TB1 INLET depth by hrs Area = 294. ac, 19.89% Impervious, Depth > 3.1" for 2 Year St event = 12.4 hrs, Volume= af = 12.4 hrs, Volume= af, Atten= %, Lag=. min Primary = 12.1 hrs, Volume= af Secondary = hrs, Volume= af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 191.2' Device Routing Invert Outlet Devices #1 Primary 187.' 36." Round Culvert L= 82.' RCP, sq.cut end projecting, Ke=. Inlet / Outlet Invert= 187.' / 186.4' S=.73 '/' Cc=.9 n=.12, Flow Area= 7.7 sf #2 Secondary 191.2' 2.' long x 1.' breadth Broad-Crested Rectangular Weir Head (feet) Coef. (English) Primary OutFlow 12.1 hrs HW=191.82' TW=191.3' (Dynamic Tailwater) 1=Culvert (Inlet Controls 2.63 fps) Secondary OutFlow hrs HW=192.14' TW=.' (Dynamic Tailwater) 2=Broad-Crested Rectangular Weir (Weir Controls 2.8 fps) Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 2 Year St Rainfall=6.43" Printed 6/17/216 Page 22 Pond C: Inlet to Culvert Primary Secondary Area=294. ac Peak Elev=192.14'

41 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 2 Year St Rainfall=6.43" Printed 6/17/216 Page 23 for Pond C: Inlet to Culvert Time (hours) () Elevation (feet) () Primary Secondary () () Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 2 Year St Rainfall=6.43" Printed 6/17/216 Page 24 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () ()

42 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 2 Year St Rainfall=6.43" Printed 6/17/216 Page 2 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () () Trolley Brook Culvert - PROPOSED Condition Type III 24-hr Year St Rainfall=7.34" Printed 6/17/216 Page 26 Summary for Pond C: Inlet to Culvert [8] Hint: Peaked 1.4' above defined flood level [61] Hint: Exceeded Reach CB1 outlet invert hrs [63] Warning: Exceeded Reach TB1 INLET depth by hrs Area = 294. ac, 19.89% Impervious, Depth > 3.68" for Year St event = 13.8 hrs, Volume= af = 13.8 hrs, Volume= af, Atten= %, Lag=. min Primary = 12.9 hrs, Volume= af Secondary = hrs, Volume= af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 191.2' Device Routing Invert Outlet Devices #1 Primary 187.' 36." Round Culvert L= 82.' RCP, sq.cut end projecting, Ke=. Inlet / Outlet Invert= 187.' / 186.4' S=.73 '/' Cc=.9 n=.12, Flow Area= 7.7 sf #2 Secondary 191.2' 2.' long x 1.' breadth Broad-Crested Rectangular Weir Head (feet) Coef. (English) Primary OutFlow 12.9 hrs HW=191.94' TW=191.61' (Dynamic Tailwater) 1=Culvert (Inlet Controls 2.77 fps) Secondary OutFlow hrs HW=192.23' TW=.' (Dynamic Tailwater) 2=Broad-Crested Rectangular Weir (Weir Controls 3.4 fps)

43 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr Year St Rainfall=7.34" Printed 6/17/216 Page 27 Pond C: Inlet to Culvert Area=294. ac Peak Elev=192.24' Primary Secondary Trolley Brook Culvert - PROPOSED Condition Type III 24-hr Year St Rainfall=7.34" Printed 6/17/216 Page 28 for Pond C: Inlet to Culvert Time (hours) () Elevation (feet) () Primary Secondary () ()

44 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr Year St Rainfall=7.34" Printed 6/17/216 Page 29 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () () Trolley Brook Culvert - PROPOSED Condition Type III 24-hr Year St Rainfall=7.34" Printed 6/17/216 Page 3 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () ()

45 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=8.2" Printed 6/17/216 Page 31 Summary for Pond C: Inlet to Culvert [8] Hint: Peaked 1.7' above defined flood level [61] Hint: Exceeded Reach CB1 outlet invert hrs [63] Warning: Exceeded Reach TB1 INLET depth by hrs Area = 294. ac, 19.89% Impervious, Depth > 4.29" for 1 Year St event = hrs, Volume= af = hrs, Volume= af, Atten= %, Lag=. min Primary = 18.4 hrs, Volume= 6.88 af Secondary = hrs, Volume= af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 191.2' Device Routing Invert Outlet Devices #1 Primary 187.' 36." Round Culvert L= 82.' RCP, sq.cut end projecting, Ke=. Inlet / Outlet Invert= 187.' / 186.4' S=.73 '/' Cc=.9 n=.12, Flow Area= 7.7 sf #2 Secondary 191.2' 2.' long x 1.' breadth Broad-Crested Rectangular Weir Head (feet) Coef. (English) Primary OutFlow 18.4 hrs HW=191.8' TW=19.94' (Dynamic Tailwater) 1=Culvert (Inlet Controls 4.48 fps) Secondary OutFlow hrs HW=192.26' TW=.' (Dynamic Tailwater) 2=Broad-Crested Rectangular Weir (Weir Controls 3.9 fps) Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=8.2" Printed 6/17/216 Page 32 Pond C: Inlet to Culvert Area=294. ac Peak Elev=192.27' Primary Secondary

46 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=8.2" Printed 6/17/216 Page 33 for Pond C: Inlet to Culvert Time (hours) () Elevation (feet) () Primary Secondary () () Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=8.2" Printed 6/17/216 Page 34 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () ()

47 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=8.2" Printed 6/17/216 Page 3 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () () Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=8.2" Printed 6/17/216 Page 36 for Pond C: Inlet to Culvert (continued) Time (hours) () Elevation (feet) () Primary Secondary () ()

48

49 HYDROLOGIC/HYDRAULIC ANALYSIS REPORT FOR THE TROLLEY BROOK CULVERT ASHLAND, MA APPENDIX C Existing HydroCAD Report Including: Existing 1 Year Storm Event With Node Summaries for 2,, 2, & 1 Year Storm Events

50

51 N1 NW MBTA W4 ND1 NW MBTA Wetlands N2 Metcalf Ave RN1 Swale CB ND2 24" RCP Pipe N3 Foster Ave N4 6 Pleasant N Tilton Ave N6 Police/Fire N7 Downtown N8 Library CB C11 CB C12 DMH-12 CB C13 DMH-13 RC1 To Sudbury River W3 MBTA CB-1 MBTA Park RW1 Thru North Wetlands DW3 MBTA Detention W7 Chemical Brook W8 Megunko Road C1 CB DMH - 1 C2 CB DMH-2 C3 CB DMH-3 C4 CB DMH4 C CB DMH- C6 CB DMH-6 CB C6a CB C7 CB DMH-7 C8 CB DMH-8 C9 CB DMH-9 CB C1 DMH-1 DMH-11 W2 CB DW2 DW4 CB1 C CB MBTA Culvert MBTA Culverts No. Wetlands Chemical Brook S9 DS Inlet to Culvert TB1 W1 MBTA CB-2 S3 MBTA RD. CB-3 DW1 W6 No. Wetlands Nyanza-W Ret/Det S6 W Nyanza south Nyanza West Settle Ponds Settle Ponds Trolley Brook DS6 S8 Trolley Brook Nyanza east DS4 DS3 East Wetlands Nyanza South SR1 S7 East Wetlands S FL Flooding DS1 To East Wetlands SE Wetlands S1 Lorraine Dr Lorraine Detention DS2 S2 Middle School Culvert Middle School S4 South Wetlands Subcat Reach Pond Link Routing Diagram for Trolley Brook Culvert - EXISTING Condition, Printed 6/17/216

52

53 Trolley Brook Culvert - EXISTING Condition Printed 6/17/216 Page 1 Area Listing (all nodes) Area (acres) CN Description (subcatchment-numbers) acre lots, 2% imp, HSG A (S1, S2) acre lots, 2% imp, HSG C (S1) /2 acre lots, 2% imp, HSG A (N1, N2, N3) /3 acre lots, 3% imp, HSG A (N4, N) >7% Grass cover, Good, HSG A (S2) >7% Grass cover, Good, HSG C (W6) Gravel roads, HSG C (S6, S9, W, W6) Meadow, non-grazed, HSG C (S6, S8, S9, W, W7) Paved parking, HSG A (S2, S) Paved parking, HSG D (W4) Paved roads w/curbs & sewers, HSG A (S4, W6) Urban commercial, 8% imp, HSG A (N6, N7, N8) Urban industrial, 72% imp, HSG A (N1, N2, N3, N4, S7, S8, W7, W8) Water Surface, HSG A (S1, S7, S9, W).6 98 Water Surface, HSG D (W4) Woods, Good, HSG A (N1, S2, S3, S4, S, S6, S7, S8, S9, W1, W2, W3, W, W6, W7) Woods, Good, HSG C (S2, S3, W1, W2, W3, W6) Woods, Good, HSG D (S2, S3, S, S6, S7, S8, W1, W2, W3, W, W6) TOTAL AREA Trolley Brook Culvert - EXISTING Condition Printed 6/17/216 Page 2 Soil Listing (all nodes) Area (acres) Soil Group Subcatchment Numbers 2. HSG A N1, N2, N3, N4, N, N6, N7, N8, S1, S2, S3, S4, S, S6, S7, S8, S9, W1, W2, W3, W, W6, W7, W8. HSG B 76.2 HSG C S1, S2, S3, S6, S8, S9, W1, W2, W3, W, W6, W HSG D S2, S3, S, S6, S7, S8, W1, W2, W3, W4, W, W6. Other 31.9 TOTAL AREA

54 Trolley Brook Culvert - EXISTING Condition Printed 6/17/216 Page 3 Ground Covers (all nodes) HSG-A (acres) HSG-B (acres) HSG-C (acres) HSG-D (acres) Other (acres) (acres) Total Cover Ground Subcatchment Numbers acre lots, 2% imp S1, S /2 acre lots, 2% imp N1, N2, N /3 acre lots, 3% imp N4, N >7% Grass cover, Good S2, W Gravel roads S6, S9, W, W Meadow, non-grazed S6, S8, S9, W, W Paved parking S2, S, W Paved roads w/curbs & sewers S4, W Urban commercial, 8% imp N6, N7, N Urban industrial, 72% imp N1, N2, N3, N4, S7, S8, W7, W Water Surface S1, S7, S9, W4, W Woods, Good N1, S2, S3, S4, S, S6, S7, S8, S9, W1, W2, W3, W, W6, W TOTAL AREA Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 4 Time span=.-72. hrs, dt=.1 hrs, 721 points x 3 Runoff by SCS TR-2 method, UH=SCS, Weighted-CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment N1: NW MBTA Runoff Area=8.3 ac 37.98% Impervious Runoff Depth=1.31" Flow Length=7' Tc=19. min CN=8 Runoff= af Subcatchment N2: Metcalf Ave Runoff Area=2.2 ac 4.91% Impervious Runoff Depth=2.31" Tc=1. min CN=71 Runoff= af Subcatchment N3: Foster Ave Runoff Area=2.9 ac 9.3% Impervious Runoff Depth=2.7" Tc=1. min CN=74 Runoff= af Subcatchment N4: 6 Pleasant Runoff Area=3. ac 62.4% Impervious Runoff Depth=2.74" Tc=1. min CN=76 Runoff= af Subcatchment N: Tilton Ave Runoff Area=3.8 ac 3.% Impervious Runoff Depth=1.24" Tc=1. min CN=7 Runoff= af Subcatchment N6: Police/Fire Runoff Area=2.8 ac 8.% Impervious Runoff Depth=4.1" Tc=1. min CN=89 Runoff= af Subcatchment N7: Downtown Runoff Area=3.4 ac 8.% Impervious Runoff Depth=4.1" Tc=1. min CN=89 Runoff= af Subcatchment N8: Library Runoff Area=.8 ac 8.% Impervious Runoff Depth=4.1" Tc=1. min CN=89 Runoff= af Subcatchment S1: Lorraine Dr Runoff Area=22.3 ac 2.72% Impervious Runoff Depth=2.39" Flow Length=2,' Tc=16.3 min CN=72 Runoff= af Subcatchment S2: Middle School Runoff Area=63. ac 1.24% Impervious Runoff Depth=.8" Flow Length=2,3' Tc=4.2 min CN= Runoff= af Subcatchment S3: MBTA RD. CB-3 Runoff Area=7. ac.% Impervious Runoff Depth=.98" Flow Length=1,98' Tc=38.8 min CN=3 Runoff= af Subcatchment S4: South Wetlands Runoff Area=22.4 ac 4.46% Impervious Runoff Depth=.7" Flow Length=1,8' Tc=41.2 min CN=33 Runoff= af Subcatchment S: SE Wetlands Runoff Area=17. ac 2.94% Impervious Runoff Depth=.22" Flow Length=9' Tc=37.7 min CN=38 Runoff=.3.36 af Subcatchment S6: Nyanza south Runoff Area=17. ac.% Impervious Runoff Depth=1.2" Flow Length=1,3' Tc=36.4 min CN=61 Runoff= af Subcatchment S7: East Wetlands Runoff Area=28.1 ac 36.44% Impervious Runoff Depth=1.24" Flow Length=8' Tc=32.7 min CN=7 Runoff= af Subcatchment S8: Nyanza east Runoff Area=13. ac 29.3% Impervious Runoff Depth=2.74" Flow Length=9' Tc=1.3 min CN=76 Runoff= af Subcatchment S9: Settle Ponds Runoff Area=2.2 ac 9.9% Impervious Runoff Depth=1.31" Flow Length=1' Tc=13.8 min CN=8 Runoff= af

55 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page Subcatchment W1: MBTA CB-2 Runoff Area=4. ac.% Impervious Runoff Depth=.68" Flow Length=1,31' Tc=19.4 min CN=48 Runoff= af Subcatchment W2: MBTA Culvert Runoff Area=16.3 ac.% Impervious Runoff Depth=1.4" Flow Length=1,3' Tc=31.3 min CN=4 Runoff= af Subcatchment W3: MBTA CB-1 Runoff Area=12. ac.% Impervious Runoff Depth=1.9" Flow Length=1,13' Tc=2.3 min CN=66 Runoff= af Subcatchment W4: MBTA Park Runoff Area=4. ac 1.% Impervious Runoff Depth=.1" Tc=1. min CN=98 Runoff= af Subcatchment W: Nyanza West Runoff Area=13.7 ac 7.3% Impervious Runoff Depth=1.9" Flow Length=9' Slope=.1 '/' Tc=26.3 min CN=66 Runoff= af Subcatchment W6: No. Wetlands Runoff Area=32. ac 3.44% Impervious Runoff Depth=1.38" Flow Length=1,' Tc=2.1 min CN=9 Runoff= af Subcatchment W7: Chemical Brook Runoff Area=9.9 ac 66.91% Impervious Runoff Depth=2.93" Flow Length=1,8' Tc=26.9 min CN=78 Runoff= af Subcatchment W8: Megunko Road Runoff Area=3.3 ac 72.% Impervious Runoff Depth=3.21" Flow Length=9' Slope=. '/' Tc=17.3 min CN=81 Runoff= af Reach CB1: Chemical Brook Avg. Flow Depth=1.11' Max Vel=2.8 fps = af n=.22 L=1,.' S=.23 '/' Capacity=64.47 = af Reach FL: Flooding = af = af Reach RC1: To Sudbury River = af = af Reach RN1: Swale Avg. Flow Depth=.28' Max Vel=1.8 fps = af n=.22 L=42.' S=.48 '/' Capacity= = af Reach RW1: Thru North Wetlands Avg. Flow Depth=.62' Max Vel=.1 fps = af n=.4 L=1,.' S=.2 '/' Capacity=27.3 = af Reach SR1: To East Wetlands Avg. Flow Depth=.61' Max Vel=4.43 fps = af n=.3 L=1,.' S=.33 '/' Capacity= = af Reach TB1: Trolley Brook Avg. Flow Depth=.7' Max Vel=2.67 fps = af n=.3 L=18.' S=.6 '/' Capacity=1, = af Pond C: Inlet to Culvert Peak Elev=192.1' = af Primary= af Secondary= af = af Pond C1: DMH - 1 Peak Elev=192.27' = af Primary= af Secondary= af = af Pond C1: DMH-1 Peak Elev=187.28' = af Primary= af Secondary=.. af = af Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 6 Pond C11: DMH-11 Peak Elev=186.49' = af Primary= af Secondary=.. af = af Pond C12: DMH-12 Peak Elev=18.' = af Primary= af Secondary=.. af = af Pond C13: DMH-13 Peak Elev=181.86' = af Primary= af Secondary=.. af = af Pond C2: DMH-2 Peak Elev=191.48' = af Primary= af Secondary=.72.7 af = af Pond C3: DMH-3 Peak Elev=19.7' = af Primary= af Secondary= af = af Pond C4: DMH4 Peak Elev=19.1' = af Primary= af Secondary=.. af = af Pond C: DMH- Peak Elev=189.64' = af Primary= af Secondary=.. af = af Pond C6: DMH-6 Peak Elev=189.71' = af Primary= af Secondary=.. af = af Pond C6a: CB Peak Elev=189.6' = af Primary= af Secondary= af = af Pond C7: DMH-7 Peak Elev=188.89' = af Primary= af Secondary=.. af = af Pond C8: DMH-8 Peak Elev=188.92' = af Primary= af Secondary=.. af = af Pond C9: DMH-9 Peak Elev=188.3' = af Primary= af Secondary=.. af = af Pond DS1: Lorraine Detention Peak Elev=281.74' Storage=33,938 cf = af Discarded= af Primary= af Secondary= af = af Pond DS2: Middle School Culvert Peak Elev=234.43' Storage=.629 af = af 36." Round Culvert n=.13 L=.' S=.22 '/' = af Pond DS3: Nyanza South Peak Elev=2.14' Storage=1,386 cf = af Discarded=.8.48 af Primary= af Secondary= af = af Pond DS4: East Wetlands Peak Elev=193.43' Storage= af = af Primary= af Secondary=.. af = af Pond DS: Settle Ponds Peak Elev=216.' Storage=.24 af = af =.. af Pond DS6: Trolley Brook Peak Elev=192.47' Storage=2,26 cf = af Primary= af Secondary=.. af = af

56 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 7 Pond DW1: Nyanza-W Ret/Det Peak Elev=21.81' Storage=77,12 cf = af Primary= af Secondary=.. af = af Pond DW2: MBTA Culverts Peak Elev=249.81' = af = af Pond DW3: MBTA Detention Peak Elev=199.28' Storage=.927 af = af = af Pond DW4: No. Wetlands Peak Elev=197.8' Storage=.214 af = af = af Pond ND1: NW MBTA Wetlands Peak Elev=194.82' Storage=23,92 cf = af Discarded= af Primary=.4.29 af = af Pond ND2: 24" RCP Pipe Peak Elev=193.39' = af 24." Round Culvert n=.13 L=33.' S=.3 '/' = af Total Runoff Area = 31.9 ac Runoff Volume = af Average Runoff Depth = 1.44" 8.71% Pervious = ac 19.29% Impervious = ac Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 8 Summary for Subcatchment N1: NW MBTA Runoff = 12.3 hrs, Volume=.9 af, Depth= 1.31" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description.8 4 1/2 acre lots, 2% imp, HSG A Urban industrial, 72% imp, HSG A Woods, Good, HSG A Weighted Average % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, Grass: Short n=.1 P2= 3.2" Shallow Concentrated Flow, Paved Kv= 2.3 fps Shallow Concentrated Flow, Woodland Kv=. fps Total Subcatchment N1: NW MBTA Runoff Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=8.3 ac Runoff Volume=.9 af Runoff Depth=1.31" Flow Length=7' Tc=19. min CN=8 1

57 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 9 Summary for Subcatchment N2: Metcalf Ave Runoff hrs, Volume=.423 af, Depth= 2.31" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description.8 4 1/2 acre lots, 2% imp, HSG A Urban industrial, 72% imp, HSG A Weighted Average % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () 1. Direct Entry, Min Tc Subcatchment N2: Metcalf Ave Runoff Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=2.2 ac Runoff Volume=.423 af Runoff Depth=2.31" Tc=1. min CN=71 1 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 1 Summary for Subcatchment N3: Foster Ave Runoff = hrs, Volume=.62 af, Depth= 2.7" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description.8 4 1/2 acre lots, 2% imp, HSG A Urban industrial, 72% imp, HSG A Weighted Average % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () 1. Direct Entry, Min Tc Subcatchment N3: Foster Ave Runoff Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=2.9 ac Runoff Volume=.62 af Runoff Depth=2.7" Tc=1. min CN=74 2 1

58 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 11 Summary for Subcatchment N4: 6 Pleasant Runoff = hrs, Volume=.8 af, Depth= 2.74" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Urban industrial, 72% imp, HSG A.8 7 1/3 acre lots, 3% imp, HSG A Weighted Average % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () 1. Direct Entry, Subcatchment N4: 6 Pleasant Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=3. ac Runoff Volume=.8 af Runoff Depth=2.74" Tc=1. min CN=76 Runoff Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 12 Summary for Subcatchment N: Tilton Ave Runoff = hrs, Volume=.393 af, Depth= 1.24" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description /3 acre lots, 3% imp, HSG A % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () 1. Direct Entry, Subcatchment N: Tilton Ave Runoff Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=3.8 ac Runoff Volume=.393 af Runoff Depth=1.24" Tc=1. min CN=7 1

59 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 13 Summary for Subcatchment N6: Police/Fire Runoff = hrs, Volume=.936 af, Depth= 4.1" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Urban commercial, 8% imp, HSG A.42 1.% Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () 1. Direct Entry, Subcatchment N6: Police/Fire Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=2.8 ac Runoff Volume=.936 af Runoff Depth=4.1" Tc=1. min CN=89 Runoff Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 14 Summary for Subcatchment N7: Downtown Runoff = hrs, Volume= af, Depth= 4.1" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Urban commercial, 8% imp, HSG A.1 1.% Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () 1. Direct Entry, Subcatchment N7: Downtown Runoff Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=3.4 ac Runoff Volume=1.137 af Runoff Depth=4.1" Tc=1. min CN=89 4 2

60 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 1 Summary for Subcatchment N8: Library Runoff = hrs, Volume=.267 af, Depth= 4.1" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description.8 89 Urban commercial, 8% imp, HSG A.12 1.% Pervious Area.68 8.% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () 1. Direct Entry, Subcatchment N8: Library Runoff Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=.8 ac Runoff Volume=.267 af Runoff Depth=4.1" Tc=1. min CN=89 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 16 Summary for Subcatchment S1: Lorraine Dr Runoff = hrs, Volume= 4.44 af, Depth= 2.39" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description acre lots, 2% imp, HSG C acre lots, 2% imp, HSG A.2 98 Water Surface, HSG A Weighted Average % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, Lawn Grass: Short n=.1 P2= 3.2" Shallow Concentrated Flow, Paved Kv= 2.3 fps 3.9 1, Pipe Channel, Drain System 1." Round Area= 1.2 sf Perim= 3.9' r=.31' n= , Total Subcatchment S1: Lorraine Dr Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=22.3 ac Runoff Volume=4.44 af Runoff Depth=2.39" Flow Length=2,' Tc=16.3 min CN=72 Runoff

61 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 17 Summary for Subcatchment S2: Middle School Runoff = hrs, Volume= 4.18 af, Depth=.8" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Paved parking, HSG A Woods, Good, HSG A Woods, Good, HSG D 6. 7 Woods, Good, HSG C >7% Grass cover, Good, HSG A acre lots, 2% imp, HSG A 63. Weighted Average % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, Woods: Light underbrush n=.4 P2= 3.2" Shallow Concentrated Flow, Woodland Kv=. fps Shallow Concentrated Flow, Woodland Kv=. fps Shallow Concentrated Flow, Short Grass Pasture Kv= 7. fps 4.2 2,3 Total Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page Subcatchment S2: Middle School Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=63. ac Runoff Volume=4.18 af Runoff Depth=.8" Flow Length=2,3' Tc=4.2 min CN= Runoff

62 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 19 Summary for Subcatchment S3: MBTA RD. CB-3 Runoff = hrs, Volume=.71 af, Depth=.98" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description 3. 3 Woods, Good, HSG A Woods, Good, HSG C.6 77 Woods, Good, HSG D 7. 3 Weighted Average 7. 1.% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, n=.6 P2= 3.2" 1.9 1, Shallow Concentrated Flow, Woodland Kv=. fps Shallow Concentrated Flow, Woodland Kv=. fps ,98 Total Subcatchment S3: MBTA RD. CB-3 Runoff Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=7. ac Runoff Volume=.71 af Runoff Depth=.98" Flow Length=1,98' Tc=38.8 min CN=3 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 2 Summary for Subcatchment S4: South Wetlands Runoff 1.98 hrs, Volume=.123 af, Depth=.7" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Paved roads w/curbs & sewers, HSG A Woods, Good, HSG A Weighted Average % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, Woods: Light underbrush n=.4 P2= 3.2" Shallow Concentrated Flow, Woodland Kv=. fps Shallow Concentrated Flow, Woodland Kv=. fps Shallow Concentrated Flow, Woodland Kv=. fps ,8 Total 1 1 Subcatchment S4: South Wetlands Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=22.4 ac Runoff Volume=.123 af Runoff Depth=.7" Flow Length=1,8' Tc=41.2 min CN=33 Runoff

63 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 21 Summary for Subcatchment S: SE Wetlands Runoff hrs, Volume=.36 af, Depth=.22" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Woods, Good, HSG A. 98 Paved parking, HSG A Woods, Good, HSG D Weighted Average % Pervious Area. 2.94% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, Woods: Light underbrush n=.4 P2= 3.2" Shallow Concentrated Flow, Woodland Kv=. fps Shallow Concentrated Flow, Woodland Kv=. fps Total Subcatchment S: SE Wetlands Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=17. ac Runoff Volume=.36 af Runoff Depth=.22" Flow Length=9' Tc=37.7 min CN=38 Runoff Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 22 Summary for Subcatchment S6: Nyanza south Runoff = 12.7 hrs, Volume= 2.16 af, Depth= 1.2" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description.9 89 Gravel roads, HSG C Meadow, non-grazed, HSG C Woods, Good, HSG A Woods, Good, HSG D Weighted Average % Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, Woods: Light underbrush n=.4 P2= 3.2" Shallow Concentrated Flow, Woodland Kv=. fps Shallow Concentrated Flow, Woodland Kv=. fps ,3 Total Subcatchment S6: Nyanza south Runoff Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=17. ac Runoff Volume=2.16 af Runoff Depth=1.2" Flow Length=1,3' Tc=36.4 min CN=61 2

64 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 23 Summary for Subcatchment S7: East Wetlands Runoff = 12.3 hrs, Volume= 2.94 af, Depth= 1.24" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Woods, Good, HSG A Water Surface, HSG A Woods, Good, HSG D Urban industrial, 72% imp, HSG A Weighted Average % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, Woods: Light underbrush n=.4 P2= 3.2" Shallow Concentrated Flow, Woodland Kv=. fps Shallow Concentrated Flow, Woodland Kv=. fps Total Subcatchment S7: East Wetlands Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=28.1 ac Runoff Volume=2.94 af Runoff Depth=1.24" Flow Length=8' Tc=32.7 min CN=7 Runoff Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 24 Summary for Subcatchment S8: Nyanza east Runoff = hrs, Volume= af, Depth= 2.74" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Meadow, non-grazed, HSG C. 3 Woods, Good, HSG A Woods, Good, HSG D.3 81 Urban industrial, 72% imp, HSG A Weighted Average % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, Grass: Dense n=.24 P2= 3.2" Shallow Concentrated Flow, Grassed Waterway Kv= 1. fps Total Subcatchment S8: Nyanza east Runoff Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=13. ac Runoff Volume=2.971 af Runoff Depth=2.74" Flow Length=9' Tc=1.3 min CN=76

65 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 2 Summary for Subcatchment S9: Settle Ponds Runoff = hrs, Volume=.24 af, Depth= 1.31" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description.2 89 Gravel roads, HSG C.9 71 Meadow, non-grazed, HSG C.9 3 Woods, Good, HSG A.2 98 Water Surface, HSG A Weighted Average % Pervious Area.2 9.9% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, Woods: Light underbrush n=.4 P2= 3.2" Shallow Concentrated Flow, Woodland Kv=. fps Total Subcatchment S9: Settle Ponds Runoff Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=2.2 ac Runoff Volume=.24 af Runoff Depth=1.31" Flow Length=1' Tc=13.8 min CN=8 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 26 Summary for Subcatchment W1: MBTA CB-2 Runoff = 12.4 hrs, Volume=.228 af, Depth=.68" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Woods, Good, HSG A Woods, Good, HSG C.2 77 Woods, Good, HSG D Weighted Average 4. 1.% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, n=.6 P2= 3.2" Shallow Concentrated Flow, Unpaved Kv= 16.1 fps Shallow Concentrated Flow, Unpaved Kv= 16.1 fps ,31 Total Subcatchment W1: MBTA CB-2 Runoff Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=4. ac Runoff Volume=.228 af Runoff Depth=.68" Flow Length=1,31' Tc=19.4 min CN=48

66 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 27 Summary for Subcatchment W2: MBTA Culvert Runoff = 12.2 hrs, Volume= af, Depth= 1.4" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description 6. 3 Woods, Good, HSG A Woods, Good, HSG C Woods, Good, HSG D Weighted Average % Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, n=.6 P2= 3.2" Shallow Concentrated Flow, Woodland Kv=. fps Shallow Concentrated Flow, Woodland Kv=. fps ,3 Total Subcatchment W2: MBTA Culvert Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=16.3 ac Runoff Volume=1.416 af Runoff Depth=1.4" Flow Length=1,3' Tc=31.3 min CN=4 Runoff Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 28 Summary for Subcatchment W3: MBTA CB-1 Runoff = hrs, Volume= af, Depth= 1.9" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Woods, Good, HSG A Woods, Good, HSG C.9 77 Woods, Good, HSG D Weighted Average % Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, n=.6 P2= 3.2" Shallow Concentrated Flow, Woodland Kv=. fps Shallow Concentrated Flow, Woodland Kv=. fps 2.3 1,13 Total Subcatchment W3: MBTA CB-1 Runoff Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=12. ac Runoff Volume=1.979 af Runoff Depth=1.9" Flow Length=1,13' Tc=2.3 min CN=66

67 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 29 Summary for Subcatchment W4: MBTA Park Runoff = hrs, Volume= 1.88 af, Depth=.1" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Paved parking, HSG D.6 98 Water Surface, HSG D Weighted Average 4. 1.% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () 1. Direct Entry, Subcatchment W4: MBTA Park Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=4. ac Runoff Volume=1.88 af Runoff Depth=.1" Tc=1. min CN=98 Runoff Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 3 Summary for Subcatchment W: Nyanza West Runoff = hrs, Volume= af, Depth= 1.9" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Woods, Good, HSG A Water Surface, HSG A Meadow, non-grazed, HSG C. 77 Woods, Good, HSG D.6 89 Gravel roads, HSG C Weighted Average % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, Woods: Light underbrush n=.4 P2= 3.2" Shallow Concentrated Flow, Grassed Waterway Kv= 1. fps Total Subcatchment W: Nyanza West Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=13.7 ac Runoff Volume=2.169 af Runoff Depth=1.9" Flow Length=9' Slope=.1 '/' Tc=26.3 min CN=66 Runoff

68 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 31 Summary for Subcatchment W6: No. Wetlands Runoff = hrs, Volume= af, Depth= 1.38" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Paved roads w/curbs & sewers, HSG A.2 89 Gravel roads, HSG C >7% Grass cover, Good, HSG C Woods, Good, HSG A Woods, Good, HSG C Woods, Good, HSG D Woods, Good, HSG D Weighted Average % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, Woods: Light underbrush n=.4 P2= 3.2" Shallow Concentrated Flow, Woodland Kv=. fps Channel Flow, Area= 1. sf Perim= 11.' r=.91' n= , Total Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 32 Subcatchment W6: No. Wetlands Runoff Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=32. ac Runoff Volume=3.676 af Runoff Depth=1.38" Flow Length=1,' Tc=2.1 min CN=9

69 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 33 Summary for Subcatchment W7: Chemical Brook Runoff = hrs, Volume= af, Depth= 2.93" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description. 3 Woods, Good, HSG A.2 71 Meadow, non-grazed, HSG C Urban industrial, 72% imp, HSG A Weighted Average % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, Grass: Dense n=.24 P2= 3.2" Shallow Concentrated Flow, Woodland Kv=. fps 1. 1, Shallow Concentrated Flow, Unpaved Kv= 16.1 fps ,8 Total Subcatchment W7: Chemical Brook Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=9.9 ac Runoff Volume=2.413 af Runoff Depth=2.93" Flow Length=1,8' Tc=26.9 min CN=78 Runoff Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 34 Summary for Subcatchment W8: Megunko Road Runoff = hrs, Volume=.882 af, Depth= 3.21" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Urban industrial, 72% imp, HSG A % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, Fallow n=. P2= 3.2" Shallow Concentrated Flow, Unpaved Kv= 16.1 fps Total Subcatchment W8: Megunko Road Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=3.3 ac Runoff Volume=.882 af Runoff Depth=3.21" Flow Length=9' Slope=. '/' Tc=17.3 min CN=81 Runoff

70 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 3 Summary for Reach CB1: Chemical Brook Area = 92.9 ac, 14.23% Impervious, Depth > 1.16" for 1 Year St event = hrs, Volume= af = hrs, Volume= af, Atten= 1%, Lag= 7.3 min Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Max. Velocity= 2.8 fps, Min. Travel Time= 9.7 min Avg. Velocity = 1.1 fps, Avg. Travel Time= 24.8 min Peak Storage= 1, hrs Average Depth at Peak Storage= 1.11' Bank-Full Depth= 2.' Flow Area= 18. sf, Capacity= ' x 2.' deep channel, n=.22 Earth, clean & straight Side Slope Z-value= 3. '/' Top Width= 1.' Length= 1,.' Slope=.23 '/' Inlet Invert= 19.', Outlet Invert= 192.' Reach CB1: Chemical Brook Area=92.9 ac Avg. Flow Depth=1.11' Max Vel=2.8 fps n=.22 L=1,.' S=.23 '/' Capacity=64.47 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 36 Summary for Reach FL: Flooding [4] Hint: Not Described (=) = hrs, Volume= 2.64 af = hrs, Volume= 2.64 af, Atten= %, Lag=. min Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Reach FL: Flooding

71 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 37 Summary for Reach RC1: To Sudbury River [4] Hint: Not Described (=) Area = 31.9 ac, 19.29% Impervious, Depth > 2.19" for 1 Year St event = hrs, Volume= 7.89 af = hrs, Volume= 7.89 af, Atten= %, Lag=. min Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Reach RC1: To Sudbury River Area=31.9 ac Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 38 Summary for Reach RN1: Swale Area = 1. ac, 41.2% Impervious, Depth =.78" for 1 Year St event hrs, Volume=.682 af = hrs, Volume=.682 af, Atten= 7%, Lag= 2. min Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Max. Velocity= 1.8 fps, Min. Travel Time= 3.8 min Avg. Velocity =.69 fps, Avg. Travel Time= 1.2 min Peak Storage= 1, hrs Average Depth at Peak Storage=.28' Bank-Full Depth= 2.' Flow Area= 32. sf, Capacity= ' x 2.' deep channel, n=.22 Earth, clean & straight Side Slope Z-value= 4. '/' Top Width= 24.' Length= 42.' Slope=.48 '/' Inlet Invert= 192.', Outlet Invert= 19.' Reach RN1: Swale Area=1. ac Avg. Flow Depth=.28' Max Vel=1.8 fps n=.22 L=42.' S=.48 '/' Capacity=

72 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 39 Summary for Reach RW1: Thru North Wetlands Area = 12. ac,.% Impervious, Depth = 1.9" for 1 Year St event = hrs, Volume= af = hrs, Volume= 1.96 af, Atten= 84%, Lag= 78. min Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Max. Velocity=.1 fps, Min. Travel Time= 24.9 min Avg. Velocity =.4 fps, Avg. Travel Time= min Peak Storage= 39, hrs Average Depth at Peak Storage=.62' Bank-Full Depth= 2.' Flow Area= 14. sf, Capacity= ' x 2.' deep channel, n=.4 Sheet flow: Woods+light brush Side Slope Z-value= 2. '/' Top Width= 11.' Length= 1,.' Slope=.2 '/' Inlet Invert= 22.', Outlet Invert= 199.' Reach RW1: Thru North Wetlands Area=12. ac Avg. Flow Depth=.62' Max Vel=.1 fps n=.4 L=1,.' S=.2 '/' Capacity=27.3 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 4 Summary for Reach SR1: To East Wetlands Area = 8.3 ac, 16.67% Impervious, Depth = 1.17" for 1 Year St event = hrs, Volume= 8.3 af = hrs, Volume= 8.3 af, Atten= %, Lag= 3.2 min Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Max. Velocity= 4.43 fps, Min. Travel Time= 3.8 min Avg. Velocity = 1.14 fps, Avg. Travel Time= 14.6 min Peak Storage= 7, hrs Average Depth at Peak Storage=.61' Bank-Full Depth= 2.' Flow Area= 66. sf, Capacity= ' x 2.' deep channel, n=.3 Earth, grassed & winding Side Slope Z-value= 1. '/' Top Width= 63.' Length= 1,.' Slope=.33 '/' Inlet Invert= 229.', Outlet Invert= 196.' Reach SR1: To East Wetlands Area=8.3 ac Avg. Flow Depth=.61' Max Vel=4.43 fps n=.3 L=1,.' S=.33 '/' Capacity=611.72

73 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 41 Summary for Reach TB1: Trolley Brook Area = 192. ac, 1.61% Impervious, Depth > 2.83" for 1 Year St event = 12. hrs, Volume= af = 12.6 hrs, Volume= af, Atten= %, Lag=.8 min Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Max. Velocity= 2.67 fps, Min. Travel Time= 1.1 min Avg. Velocity = 1.1 fps, Avg. Travel Time= 2. min Peak Storage= 2, hrs Average Depth at Peak Storage=.7' Bank-Full Depth= 6.' Flow Area= 198. sf, Capacity= 1, ' x 6.' deep channel, n=.3 Side Slope Z-value= 3. '/' Top Width= 1.' Length= 18.' Slope=.6 '/' Inlet Invert= 188.', Outlet Invert= 187.' Reach TB1: Trolley Brook Area=192. ac Avg. Flow Depth=.7' Max Vel=2.67 fps n=.3 L=18.' S=.6 '/' Capacity=1, Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 42 Summary for Pond C: Inlet to Culvert [8] Hint: Peaked.81' above defined flood level [61] Hint: Exceeded Reach CB1 outlet invert hrs [63] Warning: Exceeded Reach TB1 INLET depth by hrs Area = ac, 1.81% Impervious, Depth > 2.3" for 1 Year St event hrs, Volume=.188 af hrs, Volume=.188 af, Atten= %, Lag=. min Primary = hrs, Volume= af Secondary = hrs, Volume= 2.41 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 191.2' Device Routing Invert Outlet Devices #1 Primary 187.' 36." Round Culvert L= 82.' RCP, sq.cut end projecting, Ke=. Inlet / Outlet Invert= 187.' / 186.4' S=.73 '/' Cc=.9 n=.12, Flow Area= 7.7 sf #2 Secondary 191.2' 2.' long x 1.' breadth Broad-Crested Rectangular Weir Head (feet) Coef. (English) Primary OutFlow hrs HW=191.67' TW=191.4' (Dynamic Tailwater) 1=Culvert (Inlet Controls 2.2 fps) Secondary OutFlow hrs HW=192.1' TW=.' (Dynamic Tailwater) 2=Broad-Crested Rectangular Weir (Weir Controls 2.6 fps)

74 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 43 Pond C: Inlet to Culvert Area=288.2 ac Peak Elev=192.1' Primary Secondary Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 44 Summary for Pond C1: DMH - 1 [8] Warning: Exceeded Pond C hrs ( af) [8] Warning: Exceeded Pond ND hrs ( af) Area = 3.1 ac, 17.64% Impervious, Depth > 2.16" for 1 Year St event = hrs, Volume= af = hrs, Volume= af, Atten= %, Lag=. min Primary = hrs, Volume= af Secondary = hrs, Volume=.7 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 193.' Device Routing Invert Outlet Devices #1 Primary 186.' 36." Round Culvert L= 19.' RCP, groove end projecting, Ke=.2 Inlet / Outlet Invert= 186.' / 18.63' S=.34 '/' Cc=.9 n=.12, Flow Area= 7.7 sf #2 Secondary 192.' 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=191.34' TW=191.3' (Dynamic Tailwater) 1=Culvert (Outlet Controls 1.2 fps) Secondary OutFlow hrs HW=192.27' TW=.' (Dynamic Tailwater) 2=Orifice/Grate (Weir Controls 1.69 fps) Pond C1: DMH Area=3.1 ac Peak Elev=192.27' Primary Secondary

75 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 4 Summary for Pond C1: DMH-1 [8] Warning: Exceeded Pond C hrs ( af) Area = 31.1 ac, 19.12% Impervious, Depth > 2.18" for 1 Year St event = hrs, Volume= af = hrs, Volume= af, Atten= %, Lag=. min Primary = hrs, Volume= af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= 12.1 hrs Flood Elev= 188.' Device Routing Invert Outlet Devices #1 Primary 179.' 48." W x 44." H Box Culvert L= 19.' RCP, groove end w/headwall, Ke=.2 Inlet / Outlet Invert= 179.' / 177.9' S=.6 '/' Cc=.9 n=.2, Flow Area= sf #2 Secondary 188.' 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=186.8' TW=186.23' (Dynamic Tailwater) 1=Culvert (Outlet Controls 2.84 fps) Secondary OutFlow hrs HW=179.1' TW=.' (Dynamic Tailwater) 2=Orifice/Grate ( Controls. ) Pond C1: DMH-1 Primary Secondary Area=31.1 ac Peak Elev=187.28' Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 46 Summary for Pond C11: DMH-11 [8] Warning: Exceeded Pond C hrs ( af) Area = 31.1 ac, 19.12% Impervious, Depth > 2.18" for 1 Year St event = hrs, Volume= af = hrs, Volume= af, Atten= %, Lag=. min Primary = hrs, Volume= af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 187.' Device Routing Invert Outlet Devices #1 Primary 178.' 36." Round Culvert L= 87.' RCP, groove end w/headwall, Ke=.2 Inlet / Outlet Invert= 178.' / 177.6' S=.46 '/' Cc=.9 n=.12, Flow Area= 7.7 sf #2 Secondary 187.' 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=186.23' TW=184.88' (Dynamic Tailwater) 1=Culvert (Inlet Controls 6.98 fps) Secondary OutFlow hrs HW=178.3' TW=.' (Dynamic Tailwater) 2=Orifice/Grate ( Controls. ) Pond C11: DMH-11 Primary Secondary Area=31.1 ac Peak Elev=186.49'

76 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 47 Summary for Pond C12: DMH-12 [8] Hint: Peaked.' above defined flood level Area = 31.1 ac, 19.12% Impervious, Depth > 2.18" for 1 Year St event = hrs, Volume= af = hrs, Volume= af, Atten= %, Lag=. min Primary = hrs, Volume= af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 18.' Device Routing Invert Outlet Devices #1 Primary 177.' 36." Round Culvert L= 49.' RCP, groove end w/headwall, Ke=.2 Inlet / Outlet Invert= 177.' / 177.4' S=.2 '/' Cc=.9 n=.2, Flow Area= 7.7 sf #2 Secondary 18.' 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=184.88' TW=181.82' (Dynamic Tailwater) 1=Culvert (Outlet Controls 8.86 fps) Secondary OutFlow hrs HW=177.4' TW=.' (Dynamic Tailwater) 2=Orifice/Grate ( Controls. ) Pond C12: DMH-12 Primary Secondary Area=31.1 ac Peak Elev=18.' Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 48 Summary for Pond C13: DMH-13 Area = 31.9 ac, 19.29% Impervious, Depth > 2.19" for 1 Year St event = hrs, Volume= 7.89 af = hrs, Volume= 7.89 af, Atten= %, Lag=. min Primary = hrs, Volume= 7.89 af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 18.' Device Routing Invert Outlet Devices #1 Primary 177.4' 48." W x 44." H Box Culvert L= 137.' RCP, groove end w/headwall, Ke=.2 Inlet / Outlet Invert= 177.4' / 177.3' S=.7 '/' Cc=.9 n=.2, Flow Area= sf #2 Secondary 18.' 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=181.82' TW=.' (Dynamic Tailwater) 1=Culvert (Barrel Controls fps) Secondary OutFlow hrs HW=177.41' TW=.' (Dynamic Tailwater) 2=Orifice/Grate ( Controls. ) Pond C13: DMH-13 Primary Secondary Area=31.9 ac Peak Elev=181.86'

77 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 49 Summary for Pond C2: DMH-2 [8] Hint: Peaked.38' above defined flood level [8] Warning: Exceeded Pond C hrs ( af) Area = 3.1 ac, 17.64% Impervious, Depth > 2.16" for 1 Year St event = hrs, Volume= af = hrs, Volume= af, Atten= %, Lag=. min Primary = hrs, Volume= af Secondary hrs, Volume=.7 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 191.1' Device Routing Invert Outlet Devices #1 Primary 18.8' 36." Round Culvert L= 26.' CPP, square edge headwall, Ke=. Inlet / Outlet Invert= 18.4' / 18.8' S= -.16 '/' Cc=.9 n=.12, Flow Area= 7.7 sf #2 Secondary 191.1' 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=191.26' TW=19.19' (Dynamic Tailwater) 1=Culvert (Outlet Controls 4.74 fps) Secondary OutFlow hrs HW=191.2' TW=.' (Dynamic Tailwater) 2=Orifice/Grate (Weir 1. fps) Pond C2: DMH Area=3.1 ac Peak Elev=191.48' Primary Secondary Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page Summary for Pond C3: DMH-3 [8] Hint: Peaked.' above defined flood level Area = 3.1 ac, 17.64% Impervious, Depth > 2.16" for 1 Year St event = hrs, Volume= af = hrs, Volume= af, Atten= %, Lag=. min Primary = hrs, Volume= 4.87 af Secondary = hrs, Volume=.31 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 19.2' Device Routing Invert Outlet Devices #1 Primary 18.6' 36." Round Culvert L= 18.6' RCP, groove end w/headwall, Ke=.2 Inlet / Outlet Invert=.' / 18.6' S= -1. '/' Cc=.9 n=.12, Flow Area= 7.7 sf #2 Secondary 19.2' 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=19.19' TW=188.9' (Dynamic Tailwater) 1=Culvert (Outlet Controls fps) Secondary OutFlow hrs HW=19.6' TW=.' (Dynamic Tailwater) 2=Orifice/Grate (Weir Controls 2.2 fps) Pond C3: DMH Area=3.1 ac Peak Elev=19.7' Primary Secondary

78 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 1 Summary for Pond C4: DMH4 Area = 38.9 ac, 17.8% Impervious, Depth > 2.1" for 1 Year St event = hrs, Volume=.262 af = hrs, Volume=.262 af, Atten= %, Lag=. min Primary = hrs, Volume=.262 af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 191.7' Device Routing Invert Outlet Devices #1 Primary 18.' 48." Round Culvert L= 176.' RCP, groove end w/headwall, Ke=.2 Inlet / Outlet Invert= 18.' / 18.1' S=.23 '/' Cc=.9 n=.13, Flow Area= 12.7 sf #2 Secondary 191.7' 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=188.9' TW=188.66' (Dynamic Tailwater) 1=Culvert (Outlet Controls 3.13 fps) Secondary OutFlow hrs HW=18.3' TW=.' (Dynamic Tailwater) 2=Orifice/Grate ( Controls. ) Pond C4: DMH Area=38.9 ac Peak Elev=19.1' Primary Secondary Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 2 Summary for Pond C: DMH- [8] Warning: Exceeded Pond C hrs ( af) Area = 38.9 ac, 17.8% Impervious, Depth > 2.1" for 1 Year St event = hrs, Volume=.262 af = hrs, Volume=.262 af, Atten= %, Lag=. min Primary = hrs, Volume=.262 af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= 12.2 hrs Flood Elev= 19.9' Device Routing Invert Outlet Devices #1 Primary 18.' 48." Round Culvert L= 128.' RCP, groove end w/headwall, Ke=.2 Inlet / Outlet Invert= 18.' / 184.6' S=.31 '/' Cc=.9 n=.12, Flow Area= 12.7 sf #2 Secondary 191.3' 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=188.66' TW=188.18' (Dynamic Tailwater) 1=Culvert (Outlet Controls 4.3 fps) Secondary OutFlow hrs HW=18.3' TW=.' (Dynamic Tailwater) 2=Orifice/Grate ( Controls. ) Pond C: DMH Area=38.9 ac Peak Elev=189.64' Primary Secondary

79 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 3 Summary for Pond C6: DMH-6 [8] Warning: Exceeded Pond C hrs ( af) Area = 38.9 ac, 17.8% Impervious, Depth > 2.1" for 1 Year St event = hrs, Volume=.262 af = hrs, Volume=.262 af, Atten= %, Lag=. min Primary = hrs, Volume=.262 af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 19.9' Device Routing Invert Outlet Devices #1 Primary 184.' 48." Round Culvert L= 164.' RCP, groove end w/headwall, Ke=.2 Inlet / Outlet Invert= 184.' / 182.6' S=.116 '/' Cc=.9 n=.13, Flow Area= 12.7 sf #2 Secondary 19.9' 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=188.18' TW=187.18' (Dynamic Tailwater) 1=Culvert (Outlet Controls fps) Secondary OutFlow hrs HW=184.2' TW=.' (Dynamic Tailwater) 2=Orifice/Grate ( Controls. ) Pond C6: DMH Area=38.9 ac Peak Elev=189.71' Primary Secondary Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 4 Summary for Pond C6a: CB [8] Hint: Peaked.6' above defined flood level [8] Warning: Exceeded Pond C hrs ( af) Area = ac, 18.4% Impervious, Depth > 2.16" for 1 Year St event = hrs, Volume= af = hrs, Volume= af, Atten= %, Lag=. min Primary = hrs, Volume= af Secondary = hrs, Volume=.18 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 189.' Device Routing Invert Outlet Devices #1 Primary 182.6' 48." Round Culvert L= 6.' RCP, groove end w/headwall, Ke=.2 Inlet / Outlet Invert= 182.' / 182.6' S= -.18 '/' Cc=.9 n=.13, Flow Area= 12.7 sf #2 Secondary 189.' 24." x 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=187.18' TW=186.81' (Dynamic Tailwater) 1=Culvert (Inlet Controls 3.6 fps) Secondary OutFlow hrs HW=189.38' TW=.' (Dynamic Tailwater) 2=Orifice/Grate (Weir Controls 2.3 fps) Pond C6a: CB Area=311.7 ac Peak Elev=189.6' Primary Secondary

80 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page Summary for Pond C7: DMH-7 [8] Warning: Exceeded Pond C6a 12.2 hrs ( af) Area = ac, 18.4% Impervious, Depth > 2.16" for 1 Year St event = hrs, Volume= af = hrs, Volume= af, Atten= %, Lag=. min Primary = hrs, Volume= af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= 12.2 hrs Flood Elev= 194.' Device Routing Invert Outlet Devices #1 Primary 182.' 48." Round Culvert L= 132.' RCP, groove end w/headwall, Ke=.2 Inlet / Outlet Invert= 182.' / 181.' S=.76 '/' Cc=.9 n=.13, Flow Area= 12.7 sf #2 Secondary 191.' 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=186.81' TW=186.89' (Dynamic Tailwater) 1=Culvert ( Controls. ) Secondary OutFlow hrs HW=182.2' TW=.' (Dynamic Tailwater) 2=Orifice/Grate ( Controls. ) Pond C7: DMH Area=311.7 ac Peak Elev=188.89' Primary Secondary Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 6 Summary for Pond C8: DMH-8 [8] Warning: Exceeded Pond C hrs ( af) Area = ac, 18.4% Impervious, Depth > 2.16" for 1 Year St event = hrs, Volume= af = hrs, Volume= af, Atten= %, Lag=. min Primary = hrs, Volume= af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= 12.2 hrs Flood Elev= 191.' Device Routing Invert Outlet Devices #1 Primary 18.8' 48." W x 44." H Box Culvert L= 219.' RCP, groove end w/headwall, Ke=.2 Inlet / Outlet Invert= 18.8' / 179.1' S=.78 '/' Cc=.9 n=.2, Flow Area= sf #2 Secondary 191.' 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=186.89' TW=186.27' (Dynamic Tailwater) 1=Culvert (Outlet Controls 2.71 fps) Secondary OutFlow hrs HW=18.81' TW=.' (Dynamic Tailwater) 2=Orifice/Grate ( Controls. ) Pond C8: DMH Area=311.7 ac Peak Elev=188.92' Primary Secondary

81 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 7 Summary for Pond C9: DMH-9 [8] Warning: Exceeded Pond C hrs ( af) Area = 31.1 ac, 19.12% Impervious, Depth > 2.18" for 1 Year St event = hrs, Volume= af = hrs, Volume= af, Atten= %, Lag=. min Primary = hrs, Volume= af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= 12.1 hrs Flood Elev= 188.' Device Routing Invert Outlet Devices #1 Primary 179.3' 48." W x 44." H Box Culvert L= 88.' RCP, groove end w/headwall, Ke=.2 Inlet / Outlet Invert= 179.3' / 179.' S=.34 '/' Cc=.9 n=.2, Flow Area= sf #2 Secondary 188.' 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=187.69' TW=186.8' (Dynamic Tailwater) 1=Culvert (Outlet Controls 4.31 fps) Secondary OutFlow hrs HW=179.31' TW=.' (Dynamic Tailwater) 2=Orifice/Grate ( Controls. ) Pond C9: DMH-9 Primary Secondary Area=31.1 ac Peak Elev=188.3' Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 8 Summary for Pond DS1: Lorraine Detention Area = 22.3 ac, 2.72% Impervious, Depth = 2.39" for 1 Year St event = hrs, Volume= 4.44 af = hrs, Volume= 4.44 af, Atten= 36%, Lag= 14.1 min Discarded hrs, Volume=.249 af Primary = hrs, Volume= af Secondary = hrs, Volume=.36 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Surf.Area= 8,27 sf Storage= 33,938 cf Plug-Flow detention time= 2.2 min calculated for 4.44 af (1% of inflow) Center-of-Mass det. time= 2.2 min ( ) Volume Invert Avail.Storage Storage Description #1 27.' 9,638 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) ,7 1,388 1, , 7,7 9, , 27, 36, , 23, 9, ' Device #1 #2 #3 Coef. (English) Head (feet) Outlet Devices 12." Round Culvert L= 1.' RCP, square edge headwall, Ke= Inlet / Outlet Invert= 27.3' / 274.' S=.13 '/' Cc=.9 n=.13, Flow Area=.79 sf 1." Round Culvert L= 1.' RCP, square edge headwall, Ke= Inlet / Outlet Invert= ' / 276.' S=.163 '/' Cc=.9 n=.13, Flow Area= 1.23 sf 12." Round Culvert L= 2.' RCP, square edge headwall, Ke= Inlet / Outlet Invert= 277.2' / 277.' S=.26 '/' Cc=.9 n=.13, Flow Area=.79 sf Discarded OutFlow hrs HW=281.74' (Free Discharge) =Exfiltration (Exfiltration Controls.46 ) Primary OutFlow hrs HW=281.74' TW=229.' (Dynamic Tailwater) 1=Culvert (Barrel Controls 9.67 fps) 2=Culvert (Barrel Controls 8.68 fps) 3=Culvert (Inlet Controls 9.28 fps) Secondary OutFlow hrs HW=281.74' TW=233.36' (Dynamic Tailwater) 4=Broad-Crested Rectangular Weir (Weir Controls 1.22 fps)

82 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 9 Pond DS1: Lorraine Detention Area=22.3 ac Peak Elev=281.74' Storage=33,938 cf Discarded Primary Secondary Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 6 Summary for Pond DS2: Middle School Culvert Area = 63. ac, 1.24% Impervious, Depth =.8" for 1 Year St event = hrs, Volume= af = hrs, Volume= 4.14 af, Atten= 31%, Lag= 2.6 min Primary = hrs, Volume= 4.14 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Surf.Area=.77 ac Storage=.629 af Plug-Flow detention time= 2.1 min calculated for 4.14 af (98% of inflow) Center-of-Mass det. time= 42. min ( ) Volume Invert Avail.Storage Storage Description #1 232.' af Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (acres) (acre-feet) (acre-feet) Device Routing Invert Outlet Devices #1 Primary 233.' 36." Round Culvert L=.' RCP, square edge headwall, Ke=. Inlet / Outlet Invert= 233.' / 231.9' S=.22 '/' Cc=.9 n=.13, Flow Area= 7.7 sf Primary OutFlow hrs HW=234.43' TW=229.6' (Dynamic Tailwater) 1=Culvert (Inlet Controls 4.7 fps)

83 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 61 Pond DS2: Middle School Culvert Area=63. ac Peak Elev=234.43' Storage=.629 af 36." Round Culvert n=.13 L=.' S=.22 '/' Primary Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 62 Summary for Pond DS3: Nyanza South Area = 24. ac,.% Impervious, Depth = 1.36" for 1 Year St event = 12.8 hrs, Volume= af = 12.9 hrs, Volume= af, Atten= %, Lag=.8 min Discarded 12.9 hrs, Volume=.48 af Primary = 12.9 hrs, Volume= af Secondary = 12.9 hrs, Volume=.847 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= 12.9 hrs Surf.Area= 1,42 sf Storage= 1,386 cf Plug-Flow detention time= 3.1 min calculated for af (1% of inflow) Center-of-Mass det. time= 3.1 min ( ) Volume Invert Avail.Storage Storage Description #1 198.' 124,8 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) ,2 1,2 1, , 39,6 4, , 84, 124,8 Device Routing Invert Outlet Devices #1 Primary 198.6' 24." Round Culvert L= 33.' RCP, sq.cut end projecting, Ke=. Inlet / Outlet Invert= 198.6' / 197.4' S=.36 '/' Cc=.9 n=.13, Flow Area= 3.14 sf #2 Secondary 199.1' 32." W x 22." H Box Culvert L=.' Box, headwall w/3 square edges, Ke=. Inlet / Outlet Invert= 199.1' / 197.9' S=.24 '/' Cc=.9 n=.2, Flow Area= 4.89 sf #3 Discarded 198.' 2.41 in/hr Exfiltration over Surface area Discarded OutFlow 12.9 hrs HW=2.14' (Free Discharge) 3=Exfiltration (Exfiltration Controls.8 ) Primary OutFlow 12.9 hrs HW=2.14' TW=192.46' (Dynamic Tailwater) 1=Culvert (Barrel Controls 4.44 fps) Secondary OutFlow 12.9 hrs HW=2.14' TW=192.99' (Dynamic Tailwater) 2=Culvert (Inlet Controls 3.27 fps)

84 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 63 Pond DS3: Nyanza South Area=24. ac Peak Elev=2.14' Storage=1,386 cf Discarded Primary Secondary Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 64 Summary for Pond DS4: East Wetlands Area = 12.8 ac, 16.99% Impervious, Depth > 2.1" for 1 Year St event = hrs, Volume= af, Incl. 2. Base Flow = hrs, Volume= 2.69 af, Atten= 68%, Lag= min Primary = hrs, Volume= 2.69 af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Starting Elev= 192.' Surf.Area=.44 ac Storage= 8.1 af Peak Elev= hrs Surf.Area= ac Storage= af (6.296 af above start) Plug-Flow detention time= 1,3.1 min calculated for af (64% of inflow) Center-of-Mass det. time= min ( 1, ,94.1 ) Volume Invert Avail.Storage Storage Description # ' af Custom Stage Data (Prismatic) Listed below Elevation Surf.Area Inc.Store Cum.Store (feet) (acres) (acre-feet) (acre-feet) ' Device #1 #2 #3 Coef. (English) Head (feet) Outlet Devices 36." Round Culvert L= 7.' CPP, square edge headwall, Ke= Inlet / Outlet Invert= 191.3' / 19.4' S=.129 '/' Cc=.9 n=.12, Flow Area= 7.7 sf 6.1' long x 3.' rise Sharp-Crested Rectangular Weir 2 End Contraction(s) 12." Round Culvert L= 3.' RCP, sq.cut end projecting, Ke= Inlet / Outlet Invert= 192.6' / 192.' S=.33 '/' Cc=.9 n=.12, Flow Area=.79 sf Primary OutFlow hrs HW=193.43' TW=191.92' (Dynamic Tailwater) 1=Culvert (Passes of potential flow) 2=Sharp-Crested Rectangular Weir (Weir Controls 3.16 fps) 3=Culvert (Barrel Controls 3.2 fps) Secondary OutFlow hrs HW=192.' TW=189.78' (Dynamic Tailwater) 4=Broad-Crested Rectangular Weir ( Controls. )

85 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 6 Pond DS4: East Wetlands Primary Secondary Area=12.8 ac Peak Elev=193.43' Storage= af Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 66 Summary for Pond DS: Settle Ponds Area = 2.2 ac, 9.9% Impervious, Depth = 1.31" for 1 Year St event = hrs, Volume=.24 af hrs, Volume=. af, Atten= 1%, Lag=. min Primary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Surf.Area=.27 ac Storage=.24 af Plug-Flow detention time= (not calculated: initial storage exceeds outflow) Center-of-Mass det. time= (not calculated: no outflow) Volume Invert Avail.Storage Storage Description #1 21.' 1.92 af Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (acres) (acre-feet) (acre-feet) Device Routing Invert Outlet Devices #1 Primary 219.7'.' long x 2.' breadth Broad-Crested Rectangular Weir Head (feet) Coef. (English) Primary OutFlow hrs HW=21.' TW=189.78' (Dynamic Tailwater) 1=Broad-Crested Rectangular Weir ( Controls. ) Pond DS: Settle Ponds Primary Area=2.2 ac Peak Elev=216.' Storage=.24 af 1.

86 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 67 Summary for Pond DS6: Trolley Brook Area = 192. ac, 1.61% Impervious, Depth > 2.84" for 1 Year St event = hrs, Volume= af, Incl. 2. Base Flow = 12. hrs, Volume= af, Atten= 22%, Lag= 19.1 min Primary = 12. hrs, Volume= af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= 12. hrs Surf.Area= 2,849 sf Storage= 2,26 cf Flood Elev= 19.8' Surf.Area= 98,3 sf Storage= 218,928 cf Plug-Flow detention time= 6. min calculated for af (1% of inflow) Center-of-Mass det. time= 4.2 min ( 1, ,812.6 ) Volume Invert Avail.Storage Storage Description # ' 48,63 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) , 4,12 4, , 8,7 13, , 226, 239, , 111, 3, , 13, 48, ' Device #1 Coef. (English) Head (feet) Outlet Devices 24." Round Culvert X 2. L= 7.' CPP, projecting, no headwall, Ke=.9 Inlet / Outlet Invert= 189.7' / 189.4' S=.4 '/' Cc=.9 n=.12, Flow Area= 3.14 sf Primary OutFlow 12. hrs HW=192.47' TW=188.7' (Dynamic Tailwater) 1=Culvert (Barrel Controls fps) Secondary OutFlow hrs HW=189.78' TW=188.' (Dynamic Tailwater) 2=Broad-Crested Rectangular Weir ( Controls. ) Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 68 Pond DS6: Trolley Brook Area=192. ac Peak Elev=192.47' Storage=2,26 cf Primary Secondary

87 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 69 Summary for Pond DW1: Nyanza-W Ret/Det Area = 13.7 ac, 7.3% Impervious, Depth = 1.9" for 1 Year St event = hrs, Volume= af hrs, Volume= 1.81 af, Atten= 97%, Lag= min Primary hrs, Volume= 1.81 af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Surf.Area= 4,423 sf Storage= 77,12 cf Plug-Flow detention time= 1,33. min calculated for 1.81 af (% of inflow) Center-of-Mass det. time= 9.6 min ( 1, ) Volume Invert Avail.Storage Storage Description #1 199.' 299,7 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) , 2. 2, 17,7 17, , 67, 84, , 96, 18, , 119, 299,7 24.7' Device #1 Coef. (English) Head (feet) Limited to weir flow at low heads Outlet Devices 24." Round Culvert L= 2.' CPP, square edge headwall, Ke= Inlet / Outlet Invert= 199.' / 196.2' S=.137 '/' Cc=.9 n=.12, Flow Area= 3.14 sf Primary OutFlow hrs HW=21.81' TW=197.7' (Dynamic Tailwater) 1=Culvert (Passes.48 of 2.38 potential flow) 2=Orifice/Grate (Orifice 4.3 fps) Secondary OutFlow hrs HW=199.' TW=196.' (Dynamic Tailwater) 3=Broad-Crested Rectangular Weir ( Controls. ) Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 7 Pond DW1: Nyanza-W Ret/Det Area=13.7 ac Peak Elev=21.81' Storage=77,12 cf Primary Secondary

88 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 71 Summary for Pond DW2: MBTA Culverts Area = 16.3 ac,.% Impervious, Depth = 1.4" for 1 Year St event = 12.2 hrs, Volume= af = 12.2 hrs, Volume= af, Atten= %, Lag=. min Primary = 12.2 hrs, Volume= af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= 12.2 hrs Flood Elev= 24.' Device Routing Invert Outlet Devices #1 Primary ' 36." Round Culvert L=.' RCP, groove end projecting, Ke=.2 Inlet / Outlet Invert= ' / ' S=.6 '/' Cc=.9 n=.13, Flow Area= 7.7 sf #2 Primary 249.2' 36." Round Culvert L=.' RCP, groove end projecting, Ke=.2 Inlet / Outlet Invert= 249.2' / ' S=.94 '/' Cc=.9 n=.13, Flow Area= 7.7 sf Primary OutFlow 12.2 hrs HW=249.81' TW=196.97' (Dynamic Tailwater) 1=Culvert (Inlet Controls 3.87 fps) 2=Culvert (Inlet Controls 3.18 fps) Pond DW2: MBTA Culverts Area=16.3 ac Peak Elev=249.81' Primary Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 72 Summary for Pond DW3: MBTA Detention Area = 4. ac,1.% Impervious, Depth =.1" for 1 Year St event = hrs, Volume= 1.88 af = hrs, Volume= af, Atten= 81%, Lag= 28.7 min Primary = hrs, Volume= af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Surf.Area=.4 ac Storage=.927 af Plug-Flow detention time= min calculated for af (99% of inflow) Center-of-Mass det. time= min ( 1, ) Volume Invert Avail.Storage Storage Description #1 197.' 2.47 af Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (acres) (acre-feet) (acre-feet) ' Device #1 Coef. (English) Head (feet) Outlet Devices Custom Weir/Orifice, Cv= 2.62 (C= 3.28) Head (feet). 4. Width (feet).. Primary OutFlow hrs HW=199.28' TW=197.' (Dynamic Tailwater) 1=Custom Weir/Orifice (Weir Controls 4.37 fps) 2=Broad-Crested Rectangular Weir ( Controls. )

89 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 73 Pond DW3: MBTA Detention Area=4. ac Peak Elev=199.28' Storage=.927 af Primary Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 74 Summary for Pond DW4: No. Wetlands Area = 83. ac, 7.9% Impervious, Depth > 1.48" for 1 Year St event = hrs, Volume= af = hrs, Volume= 6.74 af, Atten= 8%, Lag= min Primary = hrs, Volume= 6.74 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Surf.Area= 4.92 ac Storage=.214 af Plug-Flow detention time= min calculated for 6.74 af (64% of inflow) Center-of-Mass det. time= 389. min ( 1,46.2-1,71.3 ) Volume Invert Avail.Storage Storage Description #1 196.' 19.3 af Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (acres) (acre-feet) (acre-feet) Device Routing Invert Outlet Devices #1 Primary 197.' 12.' long x.' breadth Broad-Crested Rectangular Weir Head (feet) Coef. (English) Primary OutFlow hrs HW=197.8' TW=196.22' (Dynamic Tailwater) 1=Broad-Crested Rectangular Weir (Weir Controls 1.8 fps)

90 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 7 Pond DW4: No. Wetlands Area=83. ac Peak Elev=197.8' Storage=.214 af Primary Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 76 Summary for Pond ND1: NW MBTA Wetlands Area = 8.3 ac, 37.98% Impervious, Depth = 1.31" for 1 Year St event = 12.3 hrs, Volume=.9 af 1.78 hrs, Volume=.791 af, Atten= 91%, Lag= 28.4 min Discarded 1.78 hrs, Volume=.32 af Primary 1.78 hrs, Volume=.29 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= 1.78 hrs Surf.Area= 32,76 sf Storage= 23,92 cf Plug-Flow detention time= min calculated for.791 af (87% of inflow) Center-of-Mass det. time= 88.6 min ( 1, ) Volume Invert Avail.Storage Storage Description #1 194.' 69, cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) , , 69, 69, Device Routing Invert Outlet Devices #1 Discarded 194.' 1.2 in/hr Exfiltration over Horizontal area from 194.' - 19.' Excluded Horizontal area = 2, sf #2 Primary 194.7'.' long x 2.' breadth Broad-Crested Rectangular Weir Head (feet) Coef. (English) Discarded OutFlow 1.78 hrs HW=194.82' (Free Discharge) 1=Exfiltration (Exfiltration Controls.18 ) Primary OutFlow 1.78 hrs HW=194.82' TW=192.1' (Dynamic Tailwater) 2=Broad-Crested Rectangular Weir (Weir fps)

91 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 77 Pond ND1: NW MBTA Wetlands Area=8.3 ac Peak Elev=194.82' Storage=23,92 cf Discarded Primary Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 78 Summary for Pond ND2: 24" RCP Pipe [7] Hint: Peaked at ' (Flood elevation advised) [63] Warning: Exceeded Reach RN1 INLET depth by 12.1 hrs Area = 13.4 ac, 4.31% Impervious, Depth = 1.17" for 1 Year St event = hrs, Volume= 1.32 af = hrs, Volume= 1.32 af, Atten= %, Lag=. min Primary = hrs, Volume= 1.32 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= 12.1 hrs Device Routing Invert Outlet Devices #1 Primary 19.' 24." Round Culvert L= 33.' RCP, groove end projecting, Ke=.2 Inlet / Outlet Invert= 19.' / 189.' S=.3 '/' Cc=.9 n=.13, Flow Area= 3.14 sf Primary OutFlow hrs HW=192.86' TW=191.77' (Dynamic Tailwater) 1=Culvert (Outlet Controls 3.63 fps) Pond ND2: 24" RCP Pipe Primary Area=13.4 ac Peak Elev=193.39' 24." Round Culvert n=.13 L=33.' S=.3 '/' 2

92 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=2.73" Printed 6/17/216 Page 79 Time span=.-72. hrs, dt=.1 hrs, 721 points x 3 Runoff by SCS TR-2 method, UH=SCS, Weighted-CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment N1: NW MBTA Runoff Area=8.3 ac 37.98% Impervious Runoff Depth=.19" Flow Length=7' Tc=19. min CN=8 Runoff= af Subcatchment N2: Metcalf Ave Runoff Area=2.2 ac 4.91% Impervious Runoff Depth=.61" Tc=1. min CN=71 Runoff= af Subcatchment N3: Foster Ave Runoff Area=2.9 ac 9.3% Impervious Runoff Depth=.74" Tc=1. min CN=74 Runoff= af Subcatchment N4: 6 Pleasant Runoff Area=3. ac 62.4% Impervious Runoff Depth=.84" Tc=1. min CN=76 Runoff= af Subcatchment N: Tilton Ave Runoff Area=3.8 ac 3.% Impervious Runoff Depth=.17" Tc=1. min CN=7 Runoff=.21.4 af Subcatchment N6: Police/Fire Runoff Area=2.8 ac 8.% Impervious Runoff Depth=1.66" Tc=1. min CN=89 Runoff= af Subcatchment N7: Downtown Runoff Area=3.4 ac 8.% Impervious Runoff Depth=1.66" Tc=1. min CN=89 Runoff= af Subcatchment N8: Library Runoff Area=.8 ac 8.% Impervious Runoff Depth=1.66" Tc=1. min CN=89 Runoff= af Subcatchment S1: Lorraine Dr Runoff Area=22.3 ac 2.72% Impervious Runoff Depth=.6" Flow Length=2,' Tc=16.3 min CN=72 Runoff= af Subcatchment S2: Middle School Runoff Area=63. ac 1.24% Impervious Runoff Depth=." Flow Length=2,3' Tc=4.2 min CN= Runoff= af Subcatchment S3: MBTA RD. CB-3 Runoff Area=7. ac.% Impervious Runoff Depth=.9" Flow Length=1,98' Tc=38.8 min CN=3 Runoff=.9.4 af Subcatchment S4: South Wetlands Runoff Area=22.4 ac 4.46% Impervious Runoff Depth=." Flow Length=1,8' Tc=41.2 min CN=33 Runoff=.. af Subcatchment S: SE Wetlands Runoff Area=17. ac 2.94% Impervious Runoff Depth=." Flow Length=9' Tc=37.7 min CN=38 Runoff=.. af Subcatchment S6: Nyanza south Runoff Area=17. ac.% Impervious Runoff Depth=.27" Flow Length=1,3' Tc=36.4 min CN=61 Runoff= af Subcatchment S7: East Wetlands Runoff Area=28.1 ac 36.44% Impervious Runoff Depth=.17" Flow Length=8' Tc=32.7 min CN=7 Runoff= af Subcatchment S8: Nyanza east Runoff Area=13. ac 29.3% Impervious Runoff Depth=.84" Flow Length=9' Tc=1.3 min CN=76 Runoff= af Subcatchment S9: Settle Ponds Runoff Area=2.2 ac 9.9% Impervious Runoff Depth=.19" Flow Length=1' Tc=13.8 min CN=8 Runoff=.1.3 af Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=2.73" Printed 6/17/216 Page 8 Subcatchment W1: MBTA CB-2 Runoff Area=4. ac.% Impervious Runoff Depth=.3" Flow Length=1,31' Tc=19.4 min CN=48 Runoff=.1.9 af Subcatchment W2: MBTA Culvert Runoff Area=16.3 ac.% Impervious Runoff Depth=.11" Flow Length=1,3' Tc=31.3 min CN=4 Runoff=.26.1 af Subcatchment W3: MBTA CB-1 Runoff Area=12. ac.% Impervious Runoff Depth=.42" Flow Length=1,13' Tc=2.3 min CN=66 Runoff= af Subcatchment W4: MBTA Park Runoff Area=4. ac 1.% Impervious Runoff Depth=2." Tc=1. min CN=98 Runoff= af Subcatchment W: Nyanza West Runoff Area=13.7 ac 7.3% Impervious Runoff Depth=.42" Flow Length=9' Slope=.1 '/' Tc=26.3 min CN=66 Runoff= af Subcatchment W6: No. Wetlands Runoff Area=32. ac 3.44% Impervious Runoff Depth=.22" Flow Length=1,' Tc=2.1 min CN=9 Runoff= af Subcatchment W7: Chemical Brook Runoff Area=9.9 ac 66.91% Impervious Runoff Depth=.94" Flow Length=1,8' Tc=26.9 min CN=78 Runoff= af Subcatchment W8: Megunko Road Runoff Area=3.3 ac 72.% Impervious Runoff Depth=1.11" Flow Length=9' Slope=. '/' Tc=17.3 min CN=81 Runoff=3..3 af Reach CB1: Chemical Brook Avg. Flow Depth=.6' Max Vel=1.83 fps = af n=.22 L=1,.' S=.23 '/' Capacity=64.47 = af Reach FL: Flooding =.. af =.. af Reach RC1: To Sudbury River = af = af Reach RN1: Swale Avg. Flow Depth=.11' Max Vel=1.4 fps = af n=.22 L=42.' S=.48 '/' Capacity= = af Reach RW1: Thru North Wetlands Avg. Flow Depth=.19' Max Vel=. fps = af n=.4 L=1,.' S=.2 '/' Capacity=27.3 = af Reach SR1: To East Wetlands Avg. Flow Depth=.29' Max Vel=2.87 fps = af n=.3 L=1,.' S=.33 '/' Capacity= = af Reach TB1: Trolley Brook Avg. Flow Depth=.39' Max Vel=1.88 fps = af n=.3 L=18.' S=.6 '/' Capacity=1, = af Pond C: Inlet to Culvert Peak Elev=189.' = af Primary= af Secondary=.. af = af Pond C1: DMH - 1 Peak Elev=189.2' = af Primary= af Secondary=.. af = af Pond C1: DMH-1 Peak Elev=182.4' = af Primary= af Secondary=.. af = af

93 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=2.73" Printed 6/17/216 Page 81 Pond C11: DMH-11 Peak Elev=181.3' = af Primary= af Secondary=.. af = af Pond C12: DMH-12 Peak Elev=18.83' = af Primary= af Secondary=.. af = af Pond C13: DMH-13 Peak Elev=18.11' = af Primary= af Secondary=.. af = af Pond C2: DMH-2 Peak Elev=188.63' = af Primary= af Secondary=.. af = af Pond C3: DMH-3 Peak Elev=188.8' = af Primary= af Secondary=.. af = af Pond C4: DMH4 Peak Elev=187.73' = af Primary= af Secondary=.. af = af Pond C: DMH- Peak Elev=187.3' = af Primary= af Secondary=.. af = af Pond C6: DMH-6 Peak Elev=186.28' = af Primary= af Secondary=.. af = af Pond C6a: CB Peak Elev=184.91' = af Primary= af Secondary=.. af = af Pond C7: DMH-7 Peak Elev=184.44' = af Primary= af Secondary=.. af = af Pond C8: DMH-8 Peak Elev=183.29' = af Primary= af Secondary=.. af = af Pond C9: DMH-9 Peak Elev=182.43' = af Primary= af Secondary=.. af = af Pond DS1: Lorraine Detention Peak Elev=277.9' Storage=8,884 cf = af Discarded= af Primary= af Secondary=.. af = af Pond DS2: Middle School Culvert Peak Elev=233.18' Storage=.11 af = af 36." Round Culvert n=.13 L=.' S=.22 '/' = af Pond DS3: Nyanza South Peak Elev=199.17' Storage=49 cf = af Discarded=.4.34 af Primary= af Secondary=.1. af = af Pond DS4: East Wetlands Peak Elev=192.82' Storage=1.287 af = af Primary= af Secondary=.. af = af Pond DS: Settle Ponds Peak Elev=21.67' Storage=.3 af =.1.3 af =.. af Pond DS6: Trolley Brook Peak Elev=191.1' Storage=4,42 cf = af Primary= af Secondary=.. af = af Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=2.73" Printed 6/17/216 Page 82 Pond DW1: Nyanza-W Ret/Det Peak Elev=2.13' Storage=2,97 cf = af Primary=.. af Secondary=.. af =.. af Pond DW2: MBTA Culverts Peak Elev=249.14' =.26.1 af =.26.1 af Pond DW3: MBTA Detention Peak Elev=198.48' Storage=.1 af = af = af Pond DW4: No. Wetlands Peak Elev=197.13' Storage=2.9 af = af =.. af Pond ND1: NW MBTA Wetlands Peak Elev=194.18' Storage=4,3 cf = af Discarded=.4.11 af Primary=.. af =.4.11 af Pond ND2: 24" RCP Pipe Peak Elev=19.86' = af 24." Round Culvert n=.13 L=33.' S=.3 '/' = af Total Runoff Area = 31.9 ac Runoff Volume = 8.61 af Average Runoff Depth =.33" 8.71% Pervious = ac 19.29% Impervious = ac

94 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 2 Year St Rainfall=3.36" Printed 6/17/216 Page 83 Time span=.-72. hrs, dt=.1 hrs, 721 points x 3 Runoff by SCS TR-2 method, UH=SCS, Weighted-CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment N1: NW MBTA Runoff Area=8.3 ac 37.98% Impervious Runoff Depth=.4" Flow Length=7' Tc=19. min CN=8 Runoff= af Subcatchment N2: Metcalf Ave Runoff Area=2.2 ac 4.91% Impervious Runoff Depth=.98" Tc=1. min CN=71 Runoff= af Subcatchment N3: Foster Ave Runoff Area=2.9 ac 9.3% Impervious Runoff Depth=1.14" Tc=1. min CN=74 Runoff= af Subcatchment N4: 6 Pleasant Runoff Area=3. ac 62.4% Impervious Runoff Depth=1.26" Tc=1. min CN=76 Runoff= af Subcatchment N: Tilton Ave Runoff Area=3.8 ac 3.% Impervious Runoff Depth=.36" Tc=1. min CN=7 Runoff= af Subcatchment N6: Police/Fire Runoff Area=2.8 ac 8.% Impervious Runoff Depth=2.23" Tc=1. min CN=89 Runoff=6.3.2 af Subcatchment N7: Downtown Runoff Area=3.4 ac 8.% Impervious Runoff Depth=2.23" Tc=1. min CN=89 Runoff= af Subcatchment N8: Library Runoff Area=.8 ac 8.% Impervious Runoff Depth=2.23" Tc=1. min CN=89 Runoff= af Subcatchment S1: Lorraine Dr Runoff Area=22.3 ac 2.72% Impervious Runoff Depth=1.3" Flow Length=2,' Tc=16.3 min CN=72 Runoff= af Subcatchment S2: Middle School Runoff Area=63. ac 1.24% Impervious Runoff Depth=.16" Flow Length=2,3' Tc=4.2 min CN= Runoff=1.6.8 af Subcatchment S3: MBTA RD. CB-3 Runoff Area=7. ac.% Impervious Runoff Depth=.24" Flow Length=1,98' Tc=38.8 min CN=3 Runoff= af Subcatchment S4: South Wetlands Runoff Area=22.4 ac 4.46% Impervious Runoff Depth=." Flow Length=1,8' Tc=41.2 min CN=33 Runoff=.. af Subcatchment S: SE Wetlands Runoff Area=17. ac 2.94% Impervious Runoff Depth=." Flow Length=9' Tc=37.7 min CN=38 Runoff=.1.1 af Subcatchment S6: Nyanza south Runoff Area=17. ac.% Impervious Runoff Depth=.1" Flow Length=1,3' Tc=36.4 min CN=61 Runoff= af Subcatchment S7: East Wetlands Runoff Area=28.1 ac 36.44% Impervious Runoff Depth=.36" Flow Length=8' Tc=32.7 min CN=7 Runoff= af Subcatchment S8: Nyanza east Runoff Area=13. ac 29.3% Impervious Runoff Depth=1.26" Flow Length=9' Tc=1.3 min CN=76 Runoff= af Subcatchment S9: Settle Ponds Runoff Area=2.2 ac 9.9% Impervious Runoff Depth=.4" Flow Length=1' Tc=13.8 min CN=8 Runoff=.4.73 af Trolley Brook Culvert - EXISTING Condition Type III 24-hr 2 Year St Rainfall=3.36" Printed 6/17/216 Page 84 Subcatchment W1: MBTA CB-2 Runoff Area=4. ac.% Impervious Runoff Depth=.12" Flow Length=1,31' Tc=19.4 min CN=48 Runoff=.7.39 af Subcatchment W2: MBTA Culvert Runoff Area=16.3 ac.% Impervious Runoff Depth=.27" Flow Length=1,3' Tc=31.3 min CN=4 Runoff= af Subcatchment W3: MBTA CB-1 Runoff Area=12. ac.% Impervious Runoff Depth=.73" Flow Length=1,13' Tc=2.3 min CN=66 Runoff= af Subcatchment W4: MBTA Park Runoff Area=4. ac 1.% Impervious Runoff Depth=3.13" Tc=1. min CN=98 Runoff= af Subcatchment W: Nyanza West Runoff Area=13.7 ac 7.3% Impervious Runoff Depth=.73" Flow Length=9' Slope=.1 '/' Tc=26.3 min CN=66 Runoff= af Subcatchment W6: No. Wetlands Runoff Area=32. ac 3.44% Impervious Runoff Depth=.44" Flow Length=1,' Tc=2.1 min CN=9 Runoff= af Subcatchment W7: Chemical Brook Runoff Area=9.9 ac 66.91% Impervious Runoff Depth=1.39" Flow Length=1,8' Tc=26.9 min CN=78 Runoff= af Subcatchment W8: Megunko Road Runoff Area=3.3 ac 72.% Impervious Runoff Depth=1.6" Flow Length=9' Slope=. '/' Tc=17.3 min CN=81 Runoff= af Reach CB1: Chemical Brook Avg. Flow Depth=.7' Max Vel=2.8 fps = af n=.22 L=1,.' S=.23 '/' Capacity=64.47 = af Reach FL: Flooding =.7.8 af =.7.8 af Reach RC1: To Sudbury River = af = af Reach RN1: Swale Avg. Flow Depth=.16' Max Vel=1.3 fps = af n=.22 L=42.' S=.48 '/' Capacity= = af Reach RW1: Thru North Wetlands Avg. Flow Depth=.29' Max Vel=.7 fps = af n=.4 L=1,.' S=.2 '/' Capacity=27.3 = af Reach SR1: To East Wetlands Avg. Flow Depth=.4' Max Vel=3.47 fps = af n=.3 L=1,.' S=.33 '/' Capacity= = af Reach TB1: Trolley Brook Avg. Flow Depth=.48' Max Vel=2.13 fps = af n=.3 L=18.' S=.6 '/' Capacity=1, = af Pond C: Inlet to Culvert Peak Elev=191.2' = af Primary= af Secondary=.7.8 af = af Pond C1: DMH - 1 Peak Elev=19.67' = af Primary= af Secondary=.. af = af Pond C1: DMH-1 Peak Elev=183.6' = af Primary= af Secondary=.. af = af

95 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 2 Year St Rainfall=3.36" Printed 6/17/216 Page 8 Pond C11: DMH-11 Peak Elev=183.13' = af Primary= af Secondary=.. af = af Pond C12: DMH-12 Peak Elev=182.16' = af Primary= af Secondary=.. af = af Pond C13: DMH-13 Peak Elev=18.79' = af Primary= af Secondary=.. af = af Pond C2: DMH-2 Peak Elev=19.7' = af Primary= af Secondary=.. af = af Pond C3: DMH-3 Peak Elev=189.1' = af Primary= af Secondary=.. af = af Pond C4: DMH4 Peak Elev=188.36' = af Primary= af Secondary=.. af = af Pond C: DMH- Peak Elev=187.6' = af Primary= af Secondary=.. af = af Pond C6: DMH-6 Peak Elev=186.92' = af Primary= af Secondary=.. af = af Pond C6a: CB Peak Elev=18.8' = af Primary= af Secondary=.. af = af Pond C7: DMH-7 Peak Elev=18.37' = af Primary= af Secondary=.. af = af Pond C8: DMH-8 Peak Elev=184.62' = af Primary= af Secondary=.. af = af Pond C9: DMH-9 Peak Elev=183.98' = af Primary= af Secondary=.. af = af Pond DS1: Lorraine Detention Peak Elev=278.72' Storage=12,941 cf = af Discarded= af Primary= af Secondary=.. af = af Pond DS2: Middle School Culvert Peak Elev=233.42' Storage=.176 af =1.6.8 af 36." Round Culvert n=.13 L=.' S=.22 '/' = af Pond DS3: Nyanza South Peak Elev=199.41' Storage=92 cf = af Discarded=..38 af Primary= af Secondary= af = af Pond DS4: East Wetlands Peak Elev=192.93' Storage=1.97 af = af Primary= af Secondary=.. af = af Pond DS: Settle Ponds Peak Elev=21.8' Storage=.73 af =.4.73 af =.. af Pond DS6: Trolley Brook Peak Elev=191.32' Storage=6,879 cf = af Primary= af Secondary=.. af = af Trolley Brook Culvert - EXISTING Condition Type III 24-hr 2 Year St Rainfall=3.36" Printed 6/17/216 Page 86 Pond DW1: Nyanza-W Ret/Det Peak Elev=2.66' Storage=36,79 cf = af Primary=.. af Secondary=.. af =.. af Pond DW2: MBTA Culverts Peak Elev=249.34' = af = af Pond DW3: MBTA Detention Peak Elev=198.69' Storage=.612 af = af = af Pond DW4: No. Wetlands Peak Elev=197.47' Storage=3.47 af = af =.. af Pond ND1: NW MBTA Wetlands Peak Elev=194.3' Storage=9,273 cf = af Discarded= af Primary=.. af = af Pond ND2: 24" RCP Pipe Peak Elev=191.24' = af 24." Round Culvert n=.13 L=33.' S=.3 '/' = af Total Runoff Area = 31.9 ac Runoff Volume = af Average Runoff Depth =." 8.71% Pervious = ac 19.29% Impervious = ac

96 Trolley Brook Culvert - EXISTING Condition Type III 24-hr Year St Rainfall=4.4" Printed 6/17/216 Page 87 Time span=.-72. hrs, dt=.1 hrs, 721 points x 3 Runoff by SCS TR-2 method, UH=SCS, Weighted-CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment N1: NW MBTA Runoff Area=8.3 ac 37.98% Impervious Runoff Depth=.8" Flow Length=7' Tc=19. min CN=8 Runoff= af Subcatchment N2: Metcalf Ave Runoff Area=2.2 ac 4.91% Impervious Runoff Depth=1.67" Tc=1. min CN=71 Runoff= af Subcatchment N3: Foster Ave Runoff Area=2.9 ac 9.3% Impervious Runoff Depth=1.9" Tc=1. min CN=74 Runoff=..48 af Subcatchment N4: 6 Pleasant Runoff Area=3. ac 62.4% Impervious Runoff Depth=2." Tc=1. min CN=76 Runoff= af Subcatchment N: Tilton Ave Runoff Area=3.8 ac 3.% Impervious Runoff Depth=.8" Tc=1. min CN=7 Runoff= af Subcatchment N6: Police/Fire Runoff Area=2.8 ac 8.% Impervious Runoff Depth=3.2" Tc=1. min CN=89 Runoff= af Subcatchment N7: Downtown Runoff Area=3.4 ac 8.% Impervious Runoff Depth=3.2" Tc=1. min CN=89 Runoff= af Subcatchment N8: Library Runoff Area=.8 ac 8.% Impervious Runoff Depth=3.2" Tc=1. min CN=89 Runoff= af Subcatchment S1: Lorraine Dr Runoff Area=22.3 ac 2.72% Impervious Runoff Depth=1.7" Flow Length=2,' Tc=16.3 min CN=72 Runoff= af Subcatchment S2: Middle School Runoff Area=63. ac 1.24% Impervious Runoff Depth=.46" Flow Length=2,3' Tc=4.2 min CN= Runoff= af Subcatchment S3: MBTA RD. CB-3 Runoff Area=7. ac.% Impervious Runoff Depth=.6" Flow Length=1,98' Tc=38.8 min CN=3 Runoff= af Subcatchment S4: South Wetlands Runoff Area=22.4 ac 4.46% Impervious Runoff Depth=.1" Flow Length=1,8' Tc=41.2 min CN=33 Runoff=.3.1 af Subcatchment S: SE Wetlands Runoff Area=17. ac 2.94% Impervious Runoff Depth=.7" Flow Length=9' Tc=37.7 min CN=38 Runoff=.16.1 af Subcatchment S6: Nyanza south Runoff Area=17. ac.% Impervious Runoff Depth=1.2" Flow Length=1,3' Tc=36.4 min CN=61 Runoff= af Subcatchment S7: East Wetlands Runoff Area=28.1 ac 36.44% Impervious Runoff Depth=.8" Flow Length=8' Tc=32.7 min CN=7 Runoff= af Subcatchment S8: Nyanza east Runoff Area=13. ac 29.3% Impervious Runoff Depth=2." Flow Length=9' Tc=1.3 min CN=76 Runoff= af Subcatchment S9: Settle Ponds Runoff Area=2.2 ac 9.9% Impervious Runoff Depth=.8" Flow Length=1' Tc=13.8 min CN=8 Runoff= af Trolley Brook Culvert - EXISTING Condition Type III 24-hr Year St Rainfall=4.4" Printed 6/17/216 Page 88 Subcatchment W1: MBTA CB-2 Runoff Area=4. ac.% Impervious Runoff Depth=.38" Flow Length=1,31' Tc=19.4 min CN=48 Runoff= af Subcatchment W2: MBTA Culvert Runoff Area=16.3 ac.% Impervious Runoff Depth=.6" Flow Length=1,3' Tc=31.3 min CN=4 Runoff= af Subcatchment W3: MBTA CB-1 Runoff Area=12. ac.% Impervious Runoff Depth=1.33" Flow Length=1,13' Tc=2.3 min CN=66 Runoff= af Subcatchment W4: MBTA Park Runoff Area=4. ac 1.% Impervious Runoff Depth=4.16" Tc=1. min CN=98 Runoff= af Subcatchment W: Nyanza West Runoff Area=13.7 ac 7.3% Impervious Runoff Depth=1.33" Flow Length=9' Slope=.1 '/' Tc=26.3 min CN=66 Runoff= af Subcatchment W6: No. Wetlands Runoff Area=32. ac 3.44% Impervious Runoff Depth=.91" Flow Length=1,' Tc=2.1 min CN=9 Runoff= af Subcatchment W7: Chemical Brook Runoff Area=9.9 ac 66.91% Impervious Runoff Depth=2.21" Flow Length=1,8' Tc=26.9 min CN=78 Runoff= af Subcatchment W8: Megunko Road Runoff Area=3.3 ac 72.% Impervious Runoff Depth=2.46" Flow Length=9' Slope=. '/' Tc=17.3 min CN=81 Runoff= af Reach CB1: Chemical Brook Avg. Flow Depth=.96' Max Vel=2.38 fps = af n=.22 L=1,.' S=.23 '/' Capacity=64.47 = af Reach FL: Flooding = af = af Reach RC1: To Sudbury River = af = af Reach RN1: Swale Avg. Flow Depth=.23' Max Vel=1.64 fps = af n=.22 L=42.' S=.48 '/' Capacity= = af Reach RW1: Thru North Wetlands Avg. Flow Depth=.47' Max Vel=.9 fps = af n=.4 L=1,.' S=.2 '/' Capacity=27.3 = af Reach SR1: To East Wetlands Avg. Flow Depth=.' Max Vel=3.9 fps = af n=.3 L=1,.' S=.33 '/' Capacity= = af Reach TB1: Trolley Brook Avg. Flow Depth=.62' Max Vel=2.49 fps = af n=.3 L=18.' S=.6 '/' Capacity=1, = af Pond C: Inlet to Culvert Peak Elev=191.86' = af Primary= af Secondary= af = af Pond C1: DMH - 1 Peak Elev=191.94' = af Primary= af Secondary=.. af = af Pond C1: DMH-1 Peak Elev=186.3' = af Primary= af Secondary=.. af = af

97 Trolley Brook Culvert - EXISTING Condition Type III 24-hr Year St Rainfall=4.4" Printed 6/17/216 Page 89 Pond C11: DMH-11 Peak Elev=18.36' = af Primary= af Secondary=.. af = af Pond C12: DMH-12 Peak Elev=184.3' = af Primary= af Secondary=.. af = af Pond C13: DMH-13 Peak Elev=181.63' = af Primary= af Secondary=.. af = af Pond C2: DMH-2 Peak Elev=191.3' = af Primary= af Secondary=2.3.7 af = af Pond C3: DMH-3 Peak Elev=189.97' = af Primary= af Secondary=.. af = af Pond C4: DMH4 Peak Elev=189.18' = af Primary= af Secondary=.. af = af Pond C: DMH- Peak Elev=188.82' = af Primary= af Secondary=.. af = af Pond C6: DMH-6 Peak Elev=188.7' = af Primary= af Secondary=.. af = af Pond C6a: CB Peak Elev=188.2' = af Primary= af Secondary=.. af = af Pond C7: DMH-7 Peak Elev=187.86' = af Primary= af Secondary=.. af = af Pond C8: DMH-8 Peak Elev=187.68' = af Primary= af Secondary=.. af = af Pond C9: DMH-9 Peak Elev=186.83' = af Primary= af Secondary=.. af = af Pond DS1: Lorraine Detention Peak Elev=28.3' Storage=22,947 cf = af Discarded= af Primary= af Secondary=.. af = af Pond DS2: Middle School Culvert Peak Elev=233.9' Storage=.33 af = af 36." Round Culvert n=.13 L=.' S=.22 '/' = af Pond DS3: Nyanza South Peak Elev=199.81' Storage=979 cf = af Discarded=.6.44 af Primary= af Secondary= af = af Pond DS4: East Wetlands Peak Elev=193.17' Storage=12.62 af = af Primary= af Secondary=.. af = af Pond DS: Settle Ponds Peak Elev=216.21' Storage=.17 af = af =.. af Pond DS6: Trolley Brook Peak Elev=191.91' Storage=12,173 cf = af Primary= af Secondary=.. af = af Trolley Brook Culvert - EXISTING Condition Type III 24-hr Year St Rainfall=4.4" Printed 6/17/216 Page 9 Pond DW1: Nyanza-W Ret/Det Peak Elev=21.32' Storage=8,2 cf = af Primary= af Secondary=.. af = af Pond DW2: MBTA Culverts Peak Elev=249.61' = af = af Pond DW3: MBTA Detention Peak Elev=199.2' Storage=.788 af = af = af Pond DW4: No. Wetlands Peak Elev=197.7' Storage=4.18 af = af = af Pond ND1: NW MBTA Wetlands Peak Elev=194.7' Storage=19,842 cf = af Discarded= af Primary=.. af = af Pond ND2: 24" RCP Pipe Peak Elev=192.41' = af 24." Round Culvert n=.13 L=33.' S=.3 '/' = af Total Runoff Area = 31.9 ac Runoff Volume = af Average Runoff Depth = 1." 8.71% Pervious = ac 19.29% Impervious = ac

98 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 2 Year St Rainfall=6.43" Printed 6/17/216 Page 91 Time span=.-72. hrs, dt=.1 hrs, 721 points x 3 Runoff by SCS TR-2 method, UH=SCS, Weighted-CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment N1: NW MBTA Runoff Area=8.3 ac 37.98% Impervious Runoff Depth=2.3" Flow Length=7' Tc=19. min CN=8 Runoff= af Subcatchment N2: Metcalf Ave Runoff Area=2.2 ac 4.91% Impervious Runoff Depth=3.2" Tc=1. min CN=71 Runoff= af Subcatchment N3: Foster Ave Runoff Area=2.9 ac 9.3% Impervious Runoff Depth=3." Tc=1. min CN=74 Runoff=1..88 af Subcatchment N4: 6 Pleasant Runoff Area=3. ac 62.4% Impervious Runoff Depth=3.7" Tc=1. min CN=76 Runoff= af Subcatchment N: Tilton Ave Runoff Area=3.8 ac 3.% Impervious Runoff Depth=1.94" Tc=1. min CN=7 Runoff= af Subcatchment N6: Police/Fire Runoff Area=2.8 ac 8.% Impervious Runoff Depth=.1" Tc=1. min CN=89 Runoff= af Subcatchment N7: Downtown Runoff Area=3.4 ac 8.% Impervious Runoff Depth=.1" Tc=1. min CN=89 Runoff= af Subcatchment N8: Library Runoff Area=.8 ac 8.% Impervious Runoff Depth=.1" Tc=1. min CN=89 Runoff= af Subcatchment S1: Lorraine Dr Runoff Area=22.3 ac 2.72% Impervious Runoff Depth=3.3" Flow Length=2,' Tc=16.3 min CN=72 Runoff= af Subcatchment S2: Middle School Runoff Area=63. ac 1.24% Impervious Runoff Depth=1.36" Flow Length=2,3' Tc=4.2 min CN= Runoff= af Subcatchment S3: MBTA RD. CB-3 Runoff Area=7. ac.% Impervious Runoff Depth=1.6" Flow Length=1,98' Tc=38.8 min CN=3 Runoff= af Subcatchment S4: South Wetlands Runoff Area=22.4 ac 4.46% Impervious Runoff Depth=.2" Flow Length=1,8' Tc=41.2 min CN=33 Runoff= af Subcatchment S: SE Wetlands Runoff Area=17. ac 2.94% Impervious Runoff Depth=.1" Flow Length=9' Tc=37.7 min CN=38 Runoff= af Subcatchment S6: Nyanza south Runoff Area=17. ac.% Impervious Runoff Depth=2.3" Flow Length=1,3' Tc=36.4 min CN=61 Runoff= af Subcatchment S7: East Wetlands Runoff Area=28.1 ac 36.44% Impervious Runoff Depth=1.94" Flow Length=8' Tc=32.7 min CN=7 Runoff= af Subcatchment S8: Nyanza east Runoff Area=13. ac 29.3% Impervious Runoff Depth=3.7" Flow Length=9' Tc=1.3 min CN=76 Runoff= af Subcatchment S9: Settle Ponds Runoff Area=2.2 ac 9.9% Impervious Runoff Depth=2.3" Flow Length=1' Tc=13.8 min CN=8 Runoff= af Trolley Brook Culvert - EXISTING Condition Type III 24-hr 2 Year St Rainfall=6.43" Printed 6/17/216 Page 92 Subcatchment W1: MBTA CB-2 Runoff Area=4. ac.% Impervious Runoff Depth=1.2" Flow Length=1,31' Tc=19.4 min CN=48 Runoff=3..41 af Subcatchment W2: MBTA Culvert Runoff Area=16.3 ac.% Impervious Runoff Depth=1.69" Flow Length=1,3' Tc=31.3 min CN=4 Runoff= af Subcatchment W3: MBTA CB-1 Runoff Area=12. ac.% Impervious Runoff Depth=2.76" Flow Length=1,13' Tc=2.3 min CN=66 Runoff= af Subcatchment W4: MBTA Park Runoff Area=4. ac 1.% Impervious Runoff Depth=6.19" Tc=1. min CN=98 Runoff= af Subcatchment W: Nyanza West Runoff Area=13.7 ac 7.3% Impervious Runoff Depth=2.76" Flow Length=9' Slope=.1 '/' Tc=26.3 min CN=66 Runoff= af Subcatchment W6: No. Wetlands Runoff Area=32. ac 3.44% Impervious Runoff Depth=2.12" Flow Length=1,' Tc=2.1 min CN=9 Runoff= af Subcatchment W7: Chemical Brook Runoff Area=9.9 ac 66.91% Impervious Runoff Depth=3.96" Flow Length=1,8' Tc=26.9 min CN=78 Runoff= af Subcatchment W8: Megunko Road Runoff Area=3.3 ac 72.% Impervious Runoff Depth=4.28" Flow Length=9' Slope=. '/' Tc=17.3 min CN=81 Runoff= af Reach CB1: Chemical Brook Avg. Flow Depth=1.29' Max Vel=2.8 fps = af n=.22 L=1,.' S=.23 '/' Capacity=64.47 = af Reach FL: Flooding = af = af Reach RC1: To Sudbury River = af = af Reach RN1: Swale Avg. Flow Depth=.3' Max Vel=2.1 fps = af n=.22 L=42.' S=.48 '/' Capacity= = af Reach RW1: Thru North Wetlands Avg. Flow Depth=.82' Max Vel=.12 fps = af n=.4 L=1,.' S=.2 '/' Capacity=27.3 = af Reach SR1: To East Wetlands Avg. Flow Depth=.72' Max Vel=4.92 fps = af n=.3 L=1,.' S=.33 '/' Capacity= = af Reach TB1: Trolley Brook Avg. Flow Depth=.77' Max Vel=2.82 fps = af n=.3 L=18.' S=.6 '/' Capacity=1, = af Pond C: Inlet to Culvert Peak Elev=192.1' = af Primary= af Secondary= af = af Pond C1: DMH - 1 Peak Elev=192.41' = af Primary= af Secondary= af = af Pond C1: DMH-1 Peak Elev=188.43' = af Primary= af Secondary= af = af

99 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 2 Year St Rainfall=6.43" Printed 6/17/216 Page 93 Pond C11: DMH-11 Peak Elev=187.46' = af Primary= af Secondary=1.6.1 af = af Pond C12: DMH-12 Peak Elev=18.72' = af Primary= af Secondary= af = af Pond C13: DMH-13 Peak Elev=182.23' = af Primary= af Secondary=.. af = af Pond C2: DMH-2 Peak Elev=191.83' = af Primary= af Secondary= af = af Pond C3: DMH-3 Peak Elev=191.2' = af Primary= af Secondary= af = af Pond C4: DMH4 Peak Elev=19.97' = af Primary= af Secondary=.. af = af Pond C: DMH- Peak Elev=191.21' = af Primary= af Secondary=.. af = af Pond C6: DMH-6 Peak Elev=19.7' = af Primary= af Secondary=.43. af = af Pond C6a: CB Peak Elev=19.29' = af Primary= af Secondary= af = af Pond C7: DMH-7 Peak Elev=19.6' = af Primary= af Secondary=.. af = af Pond C8: DMH-8 Peak Elev=19.11' = af Primary= af Secondary=.. af = af Pond C9: DMH-9 Peak Elev=189.22' = af Primary= af Secondary= af = af Pond DS1: Lorraine Detention Peak Elev=282.4' Storage=4,33 cf = af Discarded=.6.28 af Primary= af Secondary= af = af Pond DS2: Middle School Culvert Peak Elev=23.17' Storage=1.431 af = af 36." Round Culvert n=.13 L=.' S=.22 '/' = af Pond DS3: Nyanza South Peak Elev=2.61' Storage=2,274 cf = af Discarded=.13.6 af Primary= af Secondary= af = af Pond DS4: East Wetlands Peak Elev=193.96' Storage=17.94 af = af Primary= af Secondary=.. af = af Pond DS: Settle Ponds Peak Elev=217.4' Storage=.372 af = af =.. af Pond DS6: Trolley Brook Peak Elev=193.16' Storage=4,21 cf = af Primary= af Secondary=.. af = af Trolley Brook Culvert - EXISTING Condition Type III 24-hr 2 Year St Rainfall=6.43" Printed 6/17/216 Page 94 Pond DW1: Nyanza-W Ret/Det Peak Elev=22.6' Storage=11,944 cf = af Primary= af Secondary=.. af = af Pond DW2: MBTA Culverts Peak Elev=2.6' = af = af Pond DW3: MBTA Detention Peak Elev=199.63' Storage=1.114 af = af = af Pond DW4: No. Wetlands Peak Elev=198.' Storage=6.28 af = af = af Pond ND1: NW MBTA Wetlands Peak Elev=194.96' Storage=28,32 cf = af Discarded=.21.7 af Primary= af = af Pond ND2: 24" RCP Pipe Peak Elev=194.7' = af 24." Round Culvert n=.13 L=33.' S=.3 '/' = af Total Runoff Area = 31.9 ac Runoff Volume = 6.4 af Average Runoff Depth = 2.14" 8.71% Pervious = ac 19.29% Impervious = ac

100 Trolley Brook Culvert - EXISTING Condition Type III 24-hr Year St Rainfall=7.34" Printed 6/17/216 Page 9 Time span=.-72. hrs, dt=.1 hrs, 721 points x 3 Runoff by SCS TR-2 method, UH=SCS, Weighted-CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment N1: NW MBTA Runoff Area=8.3 ac 37.98% Impervious Runoff Depth=2.64" Flow Length=7' Tc=19. min CN=8 Runoff= af Subcatchment N2: Metcalf Ave Runoff Area=2.2 ac 4.91% Impervious Runoff Depth=4.1" Tc=1. min CN=71 Runoff= af Subcatchment N3: Foster Ave Runoff Area=2.9 ac 9.3% Impervious Runoff Depth=4.34" Tc=1. min CN=74 Runoff= af Subcatchment N4: 6 Pleasant Runoff Area=3. ac 62.4% Impervious Runoff Depth=4.6" Tc=1. min CN=76 Runoff= af Subcatchment N: Tilton Ave Runoff Area=3.8 ac 3.% Impervious Runoff Depth=2.4" Tc=1. min CN=7 Runoff=9.4.8 af Subcatchment N6: Police/Fire Runoff Area=2.8 ac 8.% Impervious Runoff Depth=6.4" Tc=1. min CN=89 Runoff= af Subcatchment N7: Downtown Runoff Area=3.4 ac 8.% Impervious Runoff Depth=6.4" Tc=1. min CN=89 Runoff= af Subcatchment N8: Library Runoff Area=.8 ac 8.% Impervious Runoff Depth=6.4" Tc=1. min CN=89 Runoff= af Subcatchment S1: Lorraine Dr Runoff Area=22.3 ac 2.72% Impervious Runoff Depth=4.12" Flow Length=2,' Tc=16.3 min CN=72 Runoff= af Subcatchment S2: Middle School Runoff Area=63. ac 1.24% Impervious Runoff Depth=1.86" Flow Length=2,3' Tc=4.2 min CN= Runoff= af Subcatchment S3: MBTA RD. CB-3 Runoff Area=7. ac.% Impervious Runoff Depth=2.1" Flow Length=1,98' Tc=38.8 min CN=3 Runoff= af Subcatchment S4: South Wetlands Runoff Area=22.4 ac 4.46% Impervious Runoff Depth=.46" Flow Length=1,8' Tc=41.2 min CN=33 Runoff= af Subcatchment S: SE Wetlands Runoff Area=17. ac 2.94% Impervious Runoff Depth=.82" Flow Length=9' Tc=37.7 min CN=38 Runoff= af Subcatchment S6: Nyanza south Runoff Area=17. ac.% Impervious Runoff Depth=2.9" Flow Length=1,3' Tc=36.4 min CN=61 Runoff= af Subcatchment S7: East Wetlands Runoff Area=28.1 ac 36.44% Impervious Runoff Depth=2.4" Flow Length=8' Tc=32.7 min CN=7 Runoff= af Subcatchment S8: Nyanza east Runoff Area=13. ac 29.3% Impervious Runoff Depth=4.6" Flow Length=9' Tc=1.3 min CN=76 Runoff= af Subcatchment S9: Settle Ponds Runoff Area=2.2 ac 9.9% Impervious Runoff Depth=2.64" Flow Length=1' Tc=13.8 min CN=8 Runoff= af Trolley Brook Culvert - EXISTING Condition Type III 24-hr Year St Rainfall=7.34" Printed 6/17/216 Page 96 Subcatchment W1: MBTA CB-2 Runoff Area=4. ac.% Impervious Runoff Depth=1.67" Flow Length=1,31' Tc=19.4 min CN=48 Runoff=4..7 af Subcatchment W2: MBTA Culvert Runoff Area=16.3 ac.% Impervious Runoff Depth=2.24" Flow Length=1,3' Tc=31.3 min CN=4 Runoff= af Subcatchment W3: MBTA CB-1 Runoff Area=12. ac.% Impervious Runoff Depth=3.47" Flow Length=1,13' Tc=2.3 min CN=66 Runoff= af Subcatchment W4: MBTA Park Runoff Area=4. ac 1.% Impervious Runoff Depth=7.1" Tc=1. min CN=98 Runoff= af Subcatchment W: Nyanza West Runoff Area=13.7 ac 7.3% Impervious Runoff Depth=3.47" Flow Length=9' Slope=.1 '/' Tc=26.3 min CN=66 Runoff= af Subcatchment W6: No. Wetlands Runoff Area=32. ac 3.44% Impervious Runoff Depth=2.74" Flow Length=1,' Tc=2.1 min CN=9 Runoff= af Subcatchment W7: Chemical Brook Runoff Area=9.9 ac 66.91% Impervious Runoff Depth=4.78" Flow Length=1,8' Tc=26.9 min CN=78 Runoff= af Subcatchment W8: Megunko Road Runoff Area=3.3 ac 72.% Impervious Runoff Depth=.12" Flow Length=9' Slope=. '/' Tc=17.3 min CN=81 Runoff= af Reach CB1: Chemical Brook Avg. Flow Depth=1.42' Max Vel=2.9 fps = af n=.22 L=1,.' S=.23 '/' Capacity=64.47 = af Reach FL: Flooding = af = af Reach RC1: To Sudbury River = af = af Reach RN1: Swale Avg. Flow Depth=.4' Max Vel=2.26 fps = af n=.22 L=42.' S=.48 '/' Capacity= = af Reach RW1: Thru North Wetlands Avg. Flow Depth=.97' Max Vel=.13 fps = af n=.4 L=1,.' S=.2 '/' Capacity=27.3 = af Reach SR1: To East Wetlands Avg. Flow Depth=.79' Max Vel=.2 fps = af n=.3 L=1,.' S=.33 '/' Capacity= = af Reach TB1: Trolley Brook Avg. Flow Depth=.82' Max Vel=2.93 fps = af n=.3 L=18.' S=.6 '/' Capacity=1, = af Pond C: Inlet to Culvert Peak Elev=192.24' = af Primary= af Secondary= af = af Pond C1: DMH - 1 Peak Elev=192.4' = af Primary= af Secondary= af = af Pond C1: DMH-1 Peak Elev=188.76' = af Primary= af Secondary= af = af

101 Trolley Brook Culvert - EXISTING Condition Type III 24-hr Year St Rainfall=7.34" Printed 6/17/216 Page 97 Pond C11: DMH-11 Peak Elev=187.64' = af Primary= af Secondary= af = af Pond C12: DMH-12 Peak Elev=18.26' = af Primary= af Secondary=2.9.3 af = af Pond C13: DMH-13 Peak Elev=182.1' = af Primary= af Secondary=.. af = af Pond C2: DMH-2 Peak Elev=191.87' = af Primary= af Secondary= af = af Pond C3: DMH-3 Peak Elev=191.18' = af Primary= af Secondary= af = af Pond C4: DMH4 Peak Elev=191.18' = af Primary= af Secondary=.. af = af Pond C: DMH- Peak Elev=191.37' = af Primary= af Secondary=.. af = af Pond C6: DMH-6 Peak Elev=19.84' = af Primary= af Secondary= af = af Pond C6a: CB Peak Elev=19.36' = af Primary= af Secondary= af = af Pond C7: DMH-7 Peak Elev=19.79' = af Primary= af Secondary=.. af = af Pond C8: DMH-8 Peak Elev=19.1' = af Primary= af Secondary=.. af = af Pond C9: DMH-9 Peak Elev=189.8' = af Primary= af Secondary= af = af Pond DS1: Lorraine Detention Peak Elev=282.83' Storage=44,28 cf = af Discarded= af Primary= af Secondary= af = af Pond DS2: Middle School Culvert Peak Elev=23.73' Storage=2.37 af = af 36." Round Culvert n=.13 L=.' S=.22 '/' = af Pond DS3: Nyanza South Peak Elev=21.1' Storage=3,34 cf = af Discarded= af Primary= af Secondary= af = af Pond DS4: East Wetlands Peak Elev=194.' Storage= af = af Primary= af Secondary=.. af = af Pond DS: Settle Ponds Peak Elev=217.42' Storage=.48 af = af =.. af Pond DS6: Trolley Brook Peak Elev=193.78' Storage=67,618 cf = af Primary= af Secondary=.. af = af Trolley Brook Culvert - EXISTING Condition Type III 24-hr Year St Rainfall=7.34" Printed 6/17/216 Page 98 Pond DW1: Nyanza-W Ret/Det Peak Elev=23.23' Storage=14,748 cf = af Primary= af Secondary=.. af = af Pond DW2: MBTA Culverts Peak Elev=2.24' = af = af Pond DW3: MBTA Detention Peak Elev=199.88' Storage=1.24 af = af = af Pond DW4: No. Wetlands Peak Elev=198.23' Storage=7.218 af = af = af Pond ND1: NW MBTA Wetlands Peak Elev=19.12' Storage=33,847 cf = af Discarded= af Primary= af = af Pond ND2: 24" RCP Pipe Peak Elev=196.9' = af 24." Round Culvert n=.13 L=33.' S=.3 '/' = af Total Runoff Area = 31.9 ac Runoff Volume = af Average Runoff Depth = 2.74" 8.71% Pervious = ac 19.29% Impervious = ac

102 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=8.2" Printed 6/17/216 Page 99 Time span=.-72. hrs, dt=.1 hrs, 721 points x 3 Runoff by SCS TR-2 method, UH=SCS, Weighted-CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment N1: NW MBTA Runoff Area=8.3 ac 37.98% Impervious Runoff Depth=3.29" Flow Length=7' Tc=19. min CN=8 Runoff= af Subcatchment N2: Metcalf Ave Runoff Area=2.2 ac 4.91% Impervious Runoff Depth=4.8" Tc=1. min CN=71 Runoff= af Subcatchment N3: Foster Ave Runoff Area=2.9 ac 9.3% Impervious Runoff Depth=.1" Tc=1. min CN=74 Runoff= af Subcatchment N4: 6 Pleasant Runoff Area=3. ac 62.4% Impervious Runoff Depth=.39" Tc=1. min CN=76 Runoff= af Subcatchment N: Tilton Ave Runoff Area=3.8 ac 3.% Impervious Runoff Depth=3.18" Tc=1. min CN=7 Runoff= af Subcatchment N6: Police/Fire Runoff Area=2.8 ac 8.% Impervious Runoff Depth=6.93" Tc=1. min CN=89 Runoff= af Subcatchment N7: Downtown Runoff Area=3.4 ac 8.% Impervious Runoff Depth=6.93" Tc=1. min CN=89 Runoff= af Subcatchment N8: Library Runoff Area=.8 ac 8.% Impervious Runoff Depth=6.93" Tc=1. min CN=89 Runoff= af Subcatchment S1: Lorraine Dr Runoff Area=22.3 ac 2.72% Impervious Runoff Depth=4.91" Flow Length=2,' Tc=16.3 min CN=72 Runoff= af Subcatchment S2: Middle School Runoff Area=63. ac 1.24% Impervious Runoff Depth=2.4" Flow Length=2,3' Tc=4.2 min CN= Runoff= af Subcatchment S3: MBTA RD. CB-3 Runoff Area=7. ac.% Impervious Runoff Depth=2.73" Flow Length=1,98' Tc=38.8 min CN=3 Runoff= af Subcatchment S4: South Wetlands Runoff Area=22.4 ac 4.46% Impervious Runoff Depth=.72" Flow Length=1,8' Tc=41.2 min CN=33 Runoff= af Subcatchment S: SE Wetlands Runoff Area=17. ac 2.94% Impervious Runoff Depth=1.17" Flow Length=9' Tc=37.7 min CN=38 Runoff= af Subcatchment S6: Nyanza south Runoff Area=17. ac.% Impervious Runoff Depth=3.64" Flow Length=1,3' Tc=36.4 min CN=61 Runoff= af Subcatchment S7: East Wetlands Runoff Area=28.1 ac 36.44% Impervious Runoff Depth=3.18" Flow Length=8' Tc=32.7 min CN=7 Runoff= af Subcatchment S8: Nyanza east Runoff Area=13. ac 29.3% Impervious Runoff Depth=.39" Flow Length=9' Tc=1.3 min CN=76 Runoff= af Subcatchment S9: Settle Ponds Runoff Area=2.2 ac 9.9% Impervious Runoff Depth=3.29" Flow Length=1' Tc=13.8 min CN=8 Runoff= af Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=8.2" Printed 6/17/216 Page 1 Subcatchment W1: MBTA CB-2 Runoff Area=4. ac.% Impervious Runoff Depth=2.19" Flow Length=1,31' Tc=19.4 min CN=48 Runoff= af Subcatchment W2: MBTA Culvert Runoff Area=16.3 ac.% Impervious Runoff Depth=2.84" Flow Length=1,3' Tc=31.3 min CN=4 Runoff= af Subcatchment W3: MBTA CB-1 Runoff Area=12. ac.% Impervious Runoff Depth=4.21" Flow Length=1,13' Tc=2.3 min CN=66 Runoff= af Subcatchment W4: MBTA Park Runoff Area=4. ac 1.% Impervious Runoff Depth=8.1" Tc=1. min CN=98 Runoff= af Subcatchment W: Nyanza West Runoff Area=13.7 ac 7.3% Impervious Runoff Depth=4.21" Flow Length=9' Slope=.1 '/' Tc=26.3 min CN=66 Runoff= af Subcatchment W6: No. Wetlands Runoff Area=32. ac 3.44% Impervious Runoff Depth=3.41" Flow Length=1,' Tc=2.1 min CN=9 Runoff= af Subcatchment W7: Chemical Brook Runoff Area=9.9 ac 66.91% Impervious Runoff Depth=.62" Flow Length=1,8' Tc=26.9 min CN=78 Runoff= af Subcatchment W8: Megunko Road Runoff Area=3.3 ac 72.% Impervious Runoff Depth=.98" Flow Length=9' Slope=. '/' Tc=17.3 min CN=81 Runoff= af Reach CB1: Chemical Brook Avg. Flow Depth=1.6' Max Vel=3.11 fps = af n=.22 L=1,.' S=.23 '/' Capacity=64.47 = af Reach FL: Flooding = af = af Reach RC1: To Sudbury River = af = af Reach RN1: Swale Avg. Flow Depth=.44' Max Vel=2.4 fps = af n=.22 L=42.' S=.48 '/' Capacity= = af Reach RW1: Thru North Wetlands Avg. Flow Depth=1.11' Max Vel=.14 fps = af n=.4 L=1,.' S=.2 '/' Capacity=27.3 = af Reach SR1: To East Wetlands Avg. Flow Depth=.83' Max Vel=.37 fps = af n=.3 L=1,.' S=.33 '/' Capacity= = af Reach TB1: Trolley Brook Avg. Flow Depth=.86' Max Vel=3.1 fps = af n=.3 L=18.' S=.6 '/' Capacity=1, = af Pond C: Inlet to Culvert Peak Elev=192.28' = af Primary= af Secondary= af = af Pond C1: DMH - 1 Peak Elev=192.9' = af Primary= af Secondary= af = af Pond C1: DMH-1 Peak Elev=188.' = af Primary= af Secondary=1.1.6 af = af

103 Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=8.2" Printed 6/17/216 Page 11 Pond C11: DMH-11 Peak Elev=188.26' = af Primary= af Secondary= af = af Pond C12: DMH-12 Peak Elev=186.16' = af Primary= af Secondary= af = af Pond C13: DMH-13 Peak Elev=182.93' = af Primary= af Secondary=.. af = af Pond C2: DMH-2 Peak Elev=192.1' = af Primary= af Secondary= af = af Pond C3: DMH-3 Peak Elev=191.3' = af Primary= af Secondary= af = af Pond C4: DMH4 Peak Elev=191.64' = af Primary= af Secondary=.. af = af Pond C: DMH- Peak Elev=191.32' = af Primary= af Secondary=.. af = af Pond C6: DMH-6 Peak Elev=19.81' = af Primary= af Secondary=.91.1 af = af Pond C6a: CB Peak Elev=19.73' = af Primary= af Secondary= af = af Pond C7: DMH-7 Peak Elev=19.93' = af Primary= af Secondary=.. af = af Pond C8: DMH-8 Peak Elev=19.3' = af Primary= af Secondary=.. af = af Pond C9: DMH-9 Peak Elev=189.21' = af Primary= af Secondary= af = af Pond DS1: Lorraine Detention Peak Elev=283.1' Storage=48,19 cf = af Discarded= af Primary= af Secondary= af = af Pond DS2: Middle School Culvert Peak Elev=236.32' Storage=3.642 af = af 36." Round Culvert n=.13 L=.' S=.22 '/' = af Pond DS3: Nyanza South Peak Elev=21.72' Storage=,947 cf = af Discarded= af Primary= af Secondary= af = af Pond DS4: East Wetlands Peak Elev=19.26' Storage= af = af Primary= af Secondary=.. af = af Pond DS: Settle Ponds Peak Elev=217.8' Storage=.64 af = af =.. af Pond DS6: Trolley Brook Peak Elev=194.31' Storage=98,44 cf = af Primary= af Secondary=.. af = af Trolley Brook Culvert - EXISTING Condition Type III 24-hr 1 Year St Rainfall=8.2" Printed 6/17/216 Page 12 Pond DW1: Nyanza-W Ret/Det Peak Elev=23.8' Storage=172,768 cf = af Primary= af Secondary=.. af = af Pond DW2: MBTA Culverts Peak Elev=2.42' = af = af Pond DW3: MBTA Detention Peak Elev=2.13' Storage=1.392 af = af = af Pond DW4: No. Wetlands Peak Elev=198.42' Storage=8.32 af = af = af Pond ND1: NW MBTA Wetlands Peak Elev=19.29' Storage=4,96 cf = af Discarded= af Primary= af = af Pond ND2: 24" RCP Pipe Peak Elev=197.93' = af 24." Round Culvert n=.13 L=33.' S=.3 '/' = af Total Runoff Area = 31.9 ac Runoff Volume = 88.7 af Average Runoff Depth = 3.36" 8.71% Pervious = ac 19.29% Impervious = ac

104

105 HYDROLOGIC/HYDRAULIC ANALYSIS REPORT FOR THE TROLLEY BROOK CULVERT ASHLAND, MA APPENDIX D Proposed HydroCAD Report Including: Proposed 1 Year Storm Event With Node Summaries for 2,, 2, & 1 Year Storm Events

106

107 N1 NW MBTA W4 ND1 NW MBTA Wetlands N2 Metcalf Ave RN1 Swale CB ND2 24" RCP Pipe N3 Foster Ave N4 6 Pleasant N Tilton Ave N6 Police/Fire N7 Downtown N8 Library CB C11 CB C12 DMH-12 CB C13 DMH-13 RC1 To Sudbury River W3 MBTA CB-1 W2 RDAP Development DRP RDP MBTA Park RW1 Thru North Wetlands CB DW2 MBTA Culverts DW3 MBTA Detention DW4 No. Wetlands W7 Chemical Brook CB1 Chemical Brook S9 W8 Megunko Road DS C1 CB DMH - 1 C CB Inlet to Culvert C2 CB DMH-2 TB1 C3 CB DMH-3 C4 CB DMH4 C CB DMH- C6 CB DMH-6 CB C6a CB C7 CB DMH-7 C8 CB DMH-8 C9 CB DMH-9 CB C1 DMH-1 DMH-11 W1 MBTA CB-2-Direct S3 MBTA RD. CB-3 DW1 W W6 No. Wetlands Nyanza-W Ret/Det S6 Nyanza south Nyanza West Settle Ponds Settle Ponds S8 Nyanza east DS3 Nyanza South SR1 DS6 Trolley Brook DS4 Trolley Brook East Wetlands S7 East Wetlands S FL Flooding DS1 To East Wetlands SE Wetlands S1 Lorraine Dr Lorraine Detention DS2 S2 Middle School Culvert Middle School S4 South Wetlands Subcat Reach Pond Link Routing Diagram for Trolley Brook Culvert - PROPOSED Condition, Printed 6/17/216

108

109 Trolley Brook Culvert - PROPOSED Condition Printed 6/17/216 Page 1 Area Listing (all nodes) Area (acres) CN Description (subcatchment-numbers) acre lots, 2% imp, HSG A (S1, S2) acre lots, 2% imp, HSG C (S1) /2 acre lots, 2% imp, HSG A (N1, N2, N3) /3 acre lots, 3% imp, HSG A (N4, N) >7% Grass cover, Good, HSG A (S2, S3, W1, W2, W3) >7% Grass cover, Good, HSG C (W1, W2, W6) Gravel roads, HSG C (S6, S9, W, W6) Meadow, non-grazed, HSG C (S6, S8, S9, W, W7) Paved parking & roofs, HSG A (W2) Paved parking, HSG A (S2, S) Paved parking, HSG D (W4) Paved roads w/curbs & sewers, HSG A (S4, W6) Urban commercial, 8% imp, HSG A (N6, N7, N8) Urban industrial, 72% imp, HSG A (N1, N2, N3, N4, S7, S8, W7, W8) Water Surface, HSG A (S1, S7, S9, W2, W).6 98 Water Surface, HSG D (W4) Woods, Good, HSG A (N1, S2, S3, S4, S, S6, S7, S8, S9, W1, W3, W, W6, W7) Woods, Good, HSG C (S2, S3, W2, W3, W6) Woods, Good, HSG D (S2, S3, S, S6, S7, S8, W2, W, W6) TOTAL AREA Trolley Brook Culvert - PROPOSED Condition Printed 6/17/216 Page 2 Soil Listing (all nodes) Area (acres) Soil Group Subcatchment Numbers HSG A N1, N2, N3, N4, N, N6, N7, N8, S1, S2, S3, S4, S, S6, S7, S8, S9, W1, W2, W3, W, W6, W7, W8. HSG B 71.1 HSG C S1, S2, S3, S6, S8, S9, W1, W2, W3, W, W6, W HSG D S2, S3, S, S6, S7, S8, W2, W4, W, W6. Other TOTAL AREA

110 Trolley Brook Culvert - PROPOSED Condition Printed 6/17/216 Page 3 Ground Covers (all nodes) HSG-A (acres) HSG-B (acres) HSG-C (acres) HSG-D (acres) Other (acres) (acres) Total Cover Ground Subcatchment Numbers acre lots, 2% imp S1, S /2 acre lots, 2% imp N1, N2, N /3 acre lots, 3% imp N4, N >7% Grass cover, Good S2, S3, W1, W2, W3, W Gravel roads S6, S9, W, W Meadow, non-grazed S6, S8, S9, W, W Paved parking S2, S, W Paved parking & roofs W Paved roads w/curbs & sewers S4, W Urban commercial, 8% imp N6, N7, N Urban industrial, 72% imp N1, N2, N3, N4, S7, S8, W7, W Water Surface S1, S7, S9, W2, W4, W Woods, Good N1, S2, S3, S4, S, S6, S7, S8, S9, W1, W2, W3, W, W6, W TOTAL AREA Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 4 Time span=.-72. hrs, dt=.1 hrs, 721 points x 3 Runoff by SCS TR-2 method, UH=SCS, Weighted-CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment N1: NW MBTA Runoff Area=8.3 ac 37.98% Impervious Runoff Depth=1.31" Flow Length=7' Tc=19. min CN=8 Runoff= af Subcatchment N2: Metcalf Ave Runoff Area=2.2 ac 4.91% Impervious Runoff Depth=2.31" Tc=1. min CN=71 Runoff= af Subcatchment N3: Foster Ave Runoff Area=2.9 ac 9.3% Impervious Runoff Depth=2.7" Tc=1. min CN=74 Runoff= af Subcatchment N4: 6 Pleasant Runoff Area=3. ac 62.4% Impervious Runoff Depth=2.74" Tc=1. min CN=76 Runoff= af Subcatchment N: Tilton Ave Runoff Area=3.8 ac 3.% Impervious Runoff Depth=1.24" Tc=1. min CN=7 Runoff= af Subcatchment N6: Police/Fire Runoff Area=2.8 ac 8.% Impervious Runoff Depth=4.1" Tc=1. min CN=89 Runoff= af Subcatchment N7: Downtown Runoff Area=3.4 ac 8.% Impervious Runoff Depth=4.1" Tc=1. min CN=89 Runoff= af Subcatchment N8: Library Runoff Area=.8 ac 8.% Impervious Runoff Depth=4.1" Tc=1. min CN=89 Runoff= af Subcatchment S1: Lorraine Dr Runoff Area=22.3 ac 2.72% Impervious Runoff Depth=2.39" Flow Length=2,' Tc=16.3 min CN=72 Runoff= af Subcatchment S2: Middle School Runoff Area=63. ac 1.24% Impervious Runoff Depth=.8" Flow Length=2,3' Tc=4.2 min CN= Runoff= af Subcatchment S3: MBTA RD. CB-3 Runoff Area=6.6 ac.% Impervious Runoff Depth=1.11" Flow Length=1,98' Tc=38.8 min CN= Runoff= af Subcatchment S4: South Wetlands Runoff Area=22.4 ac 4.46% Impervious Runoff Depth=.7" Flow Length=1,8' Tc=41.2 min CN=33 Runoff= af Subcatchment S: SE Wetlands Runoff Area=17. ac 2.94% Impervious Runoff Depth=.22" Flow Length=9' Tc=37.7 min CN=38 Runoff=.3.36 af Subcatchment S6: Nyanza south Runoff Area=17. ac.% Impervious Runoff Depth=1.2" Flow Length=1,3' Tc=36.4 min CN=61 Runoff= af Subcatchment S7: East Wetlands Runoff Area=28.1 ac 36.44% Impervious Runoff Depth=1.24" Flow Length=8' Tc=32.7 min CN=7 Runoff= af Subcatchment S8: Nyanza east Runoff Area=13. ac 29.3% Impervious Runoff Depth=2.74" Flow Length=9' Tc=1.3 min CN=76 Runoff= af Subcatchment S9: Settle Ponds Runoff Area=2.2 ac 9.9% Impervious Runoff Depth=1.31" Flow Length=1' Tc=13.8 min CN=8 Runoff= af

111 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page Subcatchment W1: MBTA CB-2-Direct Runoff Area=2. ac.% Impervious Runoff Depth=.18" Flow Length=1,31' Tc=19.4 min CN=37 Runoff=.6.38 af Subcatchment W2: RDAP Development Runoff Area=3.7 ac 42.2% Impervious Runoff Depth=3.21" Tc=2.7 min CN=81 Runoff= af Subcatchment W3: MBTA CB-1 Runoff Area=.8 ac.% Impervious Runoff Depth=.63" Flow Length=' Tc=1.4 min CN=47 Runoff= af Subcatchment W4: MBTA Park Runoff Area=4. ac 1.% Impervious Runoff Depth=.1" Tc=1. min CN=98 Runoff= af Subcatchment W: Nyanza West Runoff Area=13.7 ac 7.3% Impervious Runoff Depth=1.9" Flow Length=9' Slope=.1 '/' Tc=26.3 min CN=66 Runoff= af Subcatchment W6: No. Wetlands Runoff Area=32. ac 3.44% Impervious Runoff Depth=1.38" Flow Length=1,' Tc=2.1 min CN=9 Runoff= af Subcatchment W7: Chemical Brook Runoff Area=9.9 ac 66.91% Impervious Runoff Depth=2.93" Flow Length=1,8' Tc=26.9 min CN=78 Runoff= af Subcatchment W8: Megunko Road Runoff Area=3.3 ac 72.% Impervious Runoff Depth=3.21" Flow Length=9' Slope=. '/' Tc=17.3 min CN=81 Runoff= af Reach CB1: Chemical Brook Avg. Flow Depth=1.11' Max Vel=2.8 fps = af n=.22 L=1,.' S=.23 '/' Capacity=64.47 = af Reach FL: Flooding = af = af Reach RC1: To Sudbury River = af = af Reach RN1: Swale Avg. Flow Depth=.28' Max Vel=1.8 fps = af n=.22 L=42.' S=.48 '/' Capacity= = af Reach RW1: Thru North Wetlands Avg. Flow Depth=.14' Max Vel=.4 fps = af n=.4 L=1,.' S=.2 '/' Capacity=27.3 = af Reach SR1: To East Wetlands Avg. Flow Depth=.61' Max Vel=4.43 fps = af n=.3 L=1,.' S=.33 '/' Capacity= = af Reach TB1: Trolley Brook Avg. Flow Depth=.7' Max Vel=2.67 fps = af n=.3 L=18.' S=.6 '/' Capacity=1, = af Pond C: Inlet to Culvert Peak Elev=192.3' = af Primary= af Secondary= af = af Pond C1: DMH - 1 Peak Elev=192.38' = af Primary= af Secondary= af = af Pond C1: DMH-1 Peak Elev=187.4' = af Primary= af Secondary=.. af = af Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 6 Pond C11: DMH-11 Peak Elev=186.83' = af Primary= af Secondary=.. af = af Pond C12: DMH-12 Peak Elev=184.74' = af Primary= af Secondary=.. af = af Pond C13: DMH-13 Peak Elev=181.82' = af Primary= af Secondary=.. af = af Pond C2: DMH-2 Peak Elev=191.9' = af Primary= af Secondary= af = af Pond C3: DMH-3 Peak Elev=19.' = af Primary= af Secondary= af = af Pond C4: DMH4 Peak Elev=19.8' = af Primary= af Secondary=.. af = af Pond C: DMH- Peak Elev=189.8' = af Primary= af Secondary=.. af = af Pond C6: DMH-6 Peak Elev=189.77' = af Primary= af Secondary=.. af = af Pond C6a: CB Peak Elev=189.' = af Primary= af Secondary= af = af Pond C7: DMH-7 Peak Elev=189.22' = af Primary= af Secondary=.. af = af Pond C8: DMH-8 Peak Elev=189.21' = af Primary= af Secondary=.. af = af Pond C9: DMH-9 Peak Elev=188.3' = af Primary= af Secondary=.. af = af Pond DRP: RDP Peak Elev=272.92' Storage=11,663 cf = af Discarded= af Primary= af Secondary=.. af = af Pond DS1: Lorraine Detention Peak Elev=281.74' Storage=33,938 cf = af Discarded= af Primary= af Secondary= af = af Pond DS2: Middle School Culvert Peak Elev=234.43' Storage=.629 af = af 36." Round Culvert n=.13 L=.' S=.22 '/' = af Pond DS3: Nyanza South Peak Elev=2.16' Storage=1,414 cf = af Discarded=.8.48 af Primary= af Secondary= af = af Pond DS4: East Wetlands Peak Elev=193.43' Storage=14.4 af = af Primary= af Secondary=.. af = af Pond DS: Settle Ponds Peak Elev=216.' Storage=.24 af = af =.. af

112 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 7 Pond DS6: Trolley Brook Peak Elev=192.47' Storage=2,418 cf = af Primary= af Secondary=.. af = af Pond DW1: Nyanza-W Ret/Det Peak Elev=21.81' Storage=77,12 cf = af Primary= af Secondary=.. af = af Pond DW2: MBTA Culverts Peak Elev=2.8' = af = af Pond DW3: MBTA Detention Peak Elev=199.28' Storage=.927 af = af = af Pond DW4: No. Wetlands Peak Elev=198.1' Storage=6.3 af = af = af Pond ND1: NW MBTA Wetlands Peak Elev=194.82' Storage=23,92 cf = af Discarded= af Primary=.4.29 af = af Pond ND2: 24" RCP Pipe Peak Elev=193.27' = af 24." Round Culvert n=.13 L=33.' S=.3 '/' = af Total Runoff Area = ac Runoff Volume = af Average Runoff Depth = 1.6" 77.% Pervious = ac 22.9% Impervious = ac Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 8 Summary for Subcatchment N1: NW MBTA Runoff = 12.3 hrs, Volume=.9 af, Depth= 1.31" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description.8 4 1/2 acre lots, 2% imp, HSG A Urban industrial, 72% imp, HSG A Woods, Good, HSG A Weighted Average % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, Grass: Short n=.1 P2= 3.2" Shallow Concentrated Flow, Paved Kv= 2.3 fps Shallow Concentrated Flow, Woodland Kv=. fps Total Subcatchment N1: NW MBTA Runoff Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=8.3 ac Runoff Volume=.9 af Runoff Depth=1.31" Flow Length=7' Tc=19. min CN=8 1

113 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 9 Summary for Subcatchment N2: Metcalf Ave Runoff hrs, Volume=.423 af, Depth= 2.31" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description.8 4 1/2 acre lots, 2% imp, HSG A Urban industrial, 72% imp, HSG A Weighted Average % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () 1. Direct Entry, Min Tc Subcatchment N2: Metcalf Ave Runoff Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=2.2 ac Runoff Volume=.423 af Runoff Depth=2.31" Tc=1. min CN=71 1 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 1 Summary for Subcatchment N3: Foster Ave Runoff = hrs, Volume=.62 af, Depth= 2.7" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description.8 4 1/2 acre lots, 2% imp, HSG A Urban industrial, 72% imp, HSG A Weighted Average % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () 1. Direct Entry, Min Tc Subcatchment N3: Foster Ave Runoff Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=2.9 ac Runoff Volume=.62 af Runoff Depth=2.7" Tc=1. min CN=74 2 1

114 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 11 Summary for Subcatchment N4: 6 Pleasant Runoff = hrs, Volume=.8 af, Depth= 2.74" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Urban industrial, 72% imp, HSG A.8 7 1/3 acre lots, 3% imp, HSG A Weighted Average % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () 1. Direct Entry, Subcatchment N4: 6 Pleasant Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=3. ac Runoff Volume=.8 af Runoff Depth=2.74" Tc=1. min CN=76 Runoff Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 12 Summary for Subcatchment N: Tilton Ave Runoff = hrs, Volume=.393 af, Depth= 1.24" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description /3 acre lots, 3% imp, HSG A % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () 1. Direct Entry, Subcatchment N: Tilton Ave Runoff Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=3.8 ac Runoff Volume=.393 af Runoff Depth=1.24" Tc=1. min CN=7 1

115 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 13 Summary for Subcatchment N6: Police/Fire Runoff = hrs, Volume=.936 af, Depth= 4.1" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Urban commercial, 8% imp, HSG A.42 1.% Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () 1. Direct Entry, Subcatchment N6: Police/Fire Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=2.8 ac Runoff Volume=.936 af Runoff Depth=4.1" Tc=1. min CN=89 Runoff Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 14 Summary for Subcatchment N7: Downtown Runoff = hrs, Volume= af, Depth= 4.1" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Urban commercial, 8% imp, HSG A.1 1.% Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () 1. Direct Entry, Subcatchment N7: Downtown Runoff Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=3.4 ac Runoff Volume=1.137 af Runoff Depth=4.1" Tc=1. min CN=89 4 2

116 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 1 Summary for Subcatchment N8: Library Runoff = hrs, Volume=.267 af, Depth= 4.1" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description.8 89 Urban commercial, 8% imp, HSG A.12 1.% Pervious Area.68 8.% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () 1. Direct Entry, Subcatchment N8: Library Runoff Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=.8 ac Runoff Volume=.267 af Runoff Depth=4.1" Tc=1. min CN=89 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 16 Summary for Subcatchment S1: Lorraine Dr Runoff = hrs, Volume= 4.44 af, Depth= 2.39" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description acre lots, 2% imp, HSG C acre lots, 2% imp, HSG A.2 98 Water Surface, HSG A Weighted Average % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, Lawn Grass: Short n=.1 P2= 3.2" Shallow Concentrated Flow, Paved Kv= 2.3 fps 3.9 1, Pipe Channel, Drain System 1." Round Area= 1.2 sf Perim= 3.9' r=.31' n= , Total Subcatchment S1: Lorraine Dr Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=22.3 ac Runoff Volume=4.44 af Runoff Depth=2.39" Flow Length=2,' Tc=16.3 min CN=72 Runoff

117 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 17 Summary for Subcatchment S2: Middle School Runoff = hrs, Volume= 4.18 af, Depth=.8" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Paved parking, HSG A Woods, Good, HSG A Woods, Good, HSG D 6. 7 Woods, Good, HSG C >7% Grass cover, Good, HSG A acre lots, 2% imp, HSG A 63. Weighted Average % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, Woods: Light underbrush n=.4 P2= 3.2" Shallow Concentrated Flow, Woodland Kv=. fps Shallow Concentrated Flow, Woodland Kv=. fps Shallow Concentrated Flow, Short Grass Pasture Kv= 7. fps 4.2 2,3 Total Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page Subcatchment S2: Middle School Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=63. ac Runoff Volume=4.18 af Runoff Depth=.8" Flow Length=2,3' Tc=4.2 min CN= Runoff

118 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 19 Summary for Subcatchment S3: MBTA RD. CB-3 Runoff = hrs, Volume=.69 af, Depth= 1.11" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description. 39 >7% Grass cover, Good, HSG A Woods, Good, HSG A Woods, Good, HSG C. 77 Woods, Good, HSG D 6.6 Weighted Average % Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, n=.6 P2= 3.2" 1.9 1, Shallow Concentrated Flow, Woodland Kv=. fps Shallow Concentrated Flow, Woodland Kv=. fps ,98 Total Subcatchment S3: MBTA RD. CB-3 Runoff Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=6.6 ac Runoff Volume=.69 af Runoff Depth=1.11" Flow Length=1,98' Tc=38.8 min CN= Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 2 Summary for Subcatchment S4: South Wetlands Runoff 1.98 hrs, Volume=.123 af, Depth=.7" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Paved roads w/curbs & sewers, HSG A Woods, Good, HSG A Weighted Average % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, Woods: Light underbrush n=.4 P2= 3.2" Shallow Concentrated Flow, Woodland Kv=. fps Shallow Concentrated Flow, Woodland Kv=. fps Shallow Concentrated Flow, Woodland Kv=. fps ,8 Total 1 1 Subcatchment S4: South Wetlands Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=22.4 ac Runoff Volume=.123 af Runoff Depth=.7" Flow Length=1,8' Tc=41.2 min CN=33 Runoff

119 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 21 Summary for Subcatchment S: SE Wetlands Runoff hrs, Volume=.36 af, Depth=.22" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Woods, Good, HSG A. 98 Paved parking, HSG A Woods, Good, HSG D Weighted Average % Pervious Area. 2.94% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, Woods: Light underbrush n=.4 P2= 3.2" Shallow Concentrated Flow, Woodland Kv=. fps Shallow Concentrated Flow, Woodland Kv=. fps Total Subcatchment S: SE Wetlands Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=17. ac Runoff Volume=.36 af Runoff Depth=.22" Flow Length=9' Tc=37.7 min CN=38 Runoff Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 22 Summary for Subcatchment S6: Nyanza south Runoff = 12.7 hrs, Volume= 2.16 af, Depth= 1.2" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description.9 89 Gravel roads, HSG C Meadow, non-grazed, HSG C Woods, Good, HSG A Woods, Good, HSG D Weighted Average % Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, Woods: Light underbrush n=.4 P2= 3.2" Shallow Concentrated Flow, Woodland Kv=. fps Shallow Concentrated Flow, Woodland Kv=. fps ,3 Total Subcatchment S6: Nyanza south Runoff Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=17. ac Runoff Volume=2.16 af Runoff Depth=1.2" Flow Length=1,3' Tc=36.4 min CN=61 2

120 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 23 Summary for Subcatchment S7: East Wetlands Runoff = 12.3 hrs, Volume= 2.94 af, Depth= 1.24" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Woods, Good, HSG A Water Surface, HSG A Woods, Good, HSG D Urban industrial, 72% imp, HSG A Weighted Average % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, Woods: Light underbrush n=.4 P2= 3.2" Shallow Concentrated Flow, Woodland Kv=. fps Shallow Concentrated Flow, Woodland Kv=. fps Total Subcatchment S7: East Wetlands Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=28.1 ac Runoff Volume=2.94 af Runoff Depth=1.24" Flow Length=8' Tc=32.7 min CN=7 Runoff Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 24 Summary for Subcatchment S8: Nyanza east Runoff = hrs, Volume= af, Depth= 2.74" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Meadow, non-grazed, HSG C. 3 Woods, Good, HSG A Woods, Good, HSG D.3 81 Urban industrial, 72% imp, HSG A Weighted Average % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, Grass: Dense n=.24 P2= 3.2" Shallow Concentrated Flow, Grassed Waterway Kv= 1. fps Total Subcatchment S8: Nyanza east Runoff Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=13. ac Runoff Volume=2.971 af Runoff Depth=2.74" Flow Length=9' Tc=1.3 min CN=76

121 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 2 Summary for Subcatchment S9: Settle Ponds Runoff = hrs, Volume=.24 af, Depth= 1.31" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description.2 89 Gravel roads, HSG C.9 71 Meadow, non-grazed, HSG C.9 3 Woods, Good, HSG A.2 98 Water Surface, HSG A Weighted Average % Pervious Area.2 9.9% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, Woods: Light underbrush n=.4 P2= 3.2" Shallow Concentrated Flow, Woodland Kv=. fps Total Subcatchment S9: Settle Ponds Runoff Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=2.2 ac Runoff Volume=.24 af Runoff Depth=1.31" Flow Length=1' Tc=13.8 min CN=8 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 26 Summary for Subcatchment W1: MBTA CB-2-Direct Runoff hrs, Volume=.38 af, Depth=.18" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Woods, Good, HSG A >7% Grass cover, Good, HSG A.2 74 >7% Grass cover, Good, HSG C Weighted Average 2. 1.% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, n=.6 P2= 3.2" Shallow Concentrated Flow, Unpaved Kv= 16.1 fps Shallow Concentrated Flow, Unpaved Kv= 16.1 fps ,31 Total Subcatchment W1: MBTA CB-2-Direct Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=2. ac Runoff Volume=.38 af Runoff Depth=.18" Flow Length=1,31' Tc=19.4 min CN=37 Runoff

122 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 27 Summary for Subcatchment W2: RDAP Development Runoff = hrs, Volume= 8.2 af, Depth= 3.21" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description * Paved parking & roofs, HSG A 6. 7 Woods, Good, HSG C Woods, Good, HSG D >7% Grass cover, Good, HSG C Water Surface, HSG A >7% Grass cover, Good, HSG A Weighted Average % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () 2.7 Direct Entry, From Permit Calcs Subcatchment W2: RDAP Development Runoff Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=3.7 ac Runoff Volume=8.2 af Runoff Depth=3.21" Tc=2.7 min CN= Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 28 Summary for Subcatchment W3: MBTA CB-1 Runoff = hrs, Volume=.34 af, Depth=.63" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Woods, Good, HSG A 2. 7 Woods, Good, HSG C >7% Grass cover, Good, HSG A.8 47 Weighted Average.8 1.% Pervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) ().7..1 Sheet Flow, Grass: Dense n=.24 P2= 3.2" Shallow Concentrated Flow, Woodland Kv=. fps Shallow Concentrated Flow, Woodland Kv=. fps 1.4 Total Subcatchment W3: MBTA CB-1 Runoff Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=.8 ac Runoff Volume=.34 af Runoff Depth=.63" Flow Length=' Tc=1.4 min CN=47

123 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 29 Summary for Subcatchment W4: MBTA Park Runoff = hrs, Volume= 1.88 af, Depth=.1" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Paved parking, HSG D.6 98 Water Surface, HSG D Weighted Average 4. 1.% Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () 1. Direct Entry, Subcatchment W4: MBTA Park Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=4. ac Runoff Volume=1.88 af Runoff Depth=.1" Tc=1. min CN=98 Runoff Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 3 Summary for Subcatchment W: Nyanza West Runoff = hrs, Volume= af, Depth= 1.9" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Woods, Good, HSG A Water Surface, HSG A Meadow, non-grazed, HSG C. 77 Woods, Good, HSG D.6 89 Gravel roads, HSG C Weighted Average % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, Woods: Light underbrush n=.4 P2= 3.2" Shallow Concentrated Flow, Grassed Waterway Kv= 1. fps Total Subcatchment W: Nyanza West Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=13.7 ac Runoff Volume=2.169 af Runoff Depth=1.9" Flow Length=9' Slope=.1 '/' Tc=26.3 min CN=66 Runoff

124 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 31 Summary for Subcatchment W6: No. Wetlands Runoff = hrs, Volume= af, Depth= 1.38" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Paved roads w/curbs & sewers, HSG A.2 89 Gravel roads, HSG C >7% Grass cover, Good, HSG C Woods, Good, HSG A Woods, Good, HSG C Woods, Good, HSG D Woods, Good, HSG D Weighted Average % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, Woods: Light underbrush n=.4 P2= 3.2" Shallow Concentrated Flow, Woodland Kv=. fps Channel Flow, Area= 1. sf Perim= 11.' r=.91' n= , Total Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 32 Subcatchment W6: No. Wetlands Runoff Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=32. ac Runoff Volume=3.676 af Runoff Depth=1.38" Flow Length=1,' Tc=2.1 min CN=9

125 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 33 Summary for Subcatchment W7: Chemical Brook Runoff = hrs, Volume= af, Depth= 2.93" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description. 3 Woods, Good, HSG A.2 71 Meadow, non-grazed, HSG C Urban industrial, 72% imp, HSG A Weighted Average % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, Grass: Dense n=.24 P2= 3.2" Shallow Concentrated Flow, Woodland Kv=. fps 1. 1, Shallow Concentrated Flow, Unpaved Kv= 16.1 fps ,8 Total Subcatchment W7: Chemical Brook Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=9.9 ac Runoff Volume=2.413 af Runoff Depth=2.93" Flow Length=1,8' Tc=26.9 min CN=78 Runoff Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 34 Summary for Subcatchment W8: Megunko Road Runoff = hrs, Volume=.882 af, Depth= 3.21" Runoff by SCS TR-2 method, UH=SCS, Weighted-CN, Time Span=.-72. hrs, dt=.1 hrs Type III 24-hr 1 Year St Rainfall=.2" Area (ac) CN Description Urban industrial, 72% imp, HSG A % Pervious Area % Impervious Area Tc Length Slope Velocity Capacity Description (min) (feet) (ft/ft) (ft/sec) () Sheet Flow, Fallow n=. P2= 3.2" Shallow Concentrated Flow, Unpaved Kv= 16.1 fps Total Subcatchment W8: Megunko Road Type III 24-hr 1 Year St Rainfall=.2" Runoff Area=3.3 ac Runoff Volume=.882 af Runoff Depth=3.21" Flow Length=9' Slope=. '/' Tc=17.3 min CN=81 Runoff

126 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 3 Summary for Reach CB1: Chemical Brook Area = 99.1 ac, 26.36% Impervious, Depth > 1.4" for 1 Year St event = hrs, Volume= af = hrs, Volume= af, Atten= 1%, Lag= 7.3 min Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Max. Velocity= 2.8 fps, Min. Travel Time= 9.7 min Avg. Velocity = 1.4 fps, Avg. Travel Time= 24.1 min Peak Storage= 1, hrs Average Depth at Peak Storage= 1.11' Bank-Full Depth= 2.' Flow Area= 18. sf, Capacity= ' x 2.' deep channel, n=.22 Earth, clean & straight Side Slope Z-value= 3. '/' Top Width= 1.' Length= 1,.' Slope=.23 '/' Inlet Invert= 19.', Outlet Invert= 192.' Reach CB1: Chemical Brook Area=99.1 ac Avg. Flow Depth=1.11' Max Vel=2.8 fps n=.22 L=1,.' S=.23 '/' Capacity=64.47 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 36 Summary for Reach FL: Flooding [4] Hint: Not Described (=) = hrs, Volume=.7 af = hrs, Volume=.7 af, Atten= %, Lag=. min Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Reach FL: Flooding

127 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 37 Summary for Reach RC1: To Sudbury River [4] Hint: Not Described (=) Area = ac, 22.9% Impervious, Depth > 2.18" for 1 Year St event = hrs, Volume= 8.31 af = hrs, Volume= 8.31 af, Atten= %, Lag=. min Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Reach RC1: To Sudbury River Area=321.7 ac Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 38 Summary for Reach RN1: Swale Area = 1. ac, 41.2% Impervious, Depth =.78" for 1 Year St event hrs, Volume=.682 af = hrs, Volume=.682 af, Atten= 7%, Lag= 2. min Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Max. Velocity= 1.8 fps, Min. Travel Time= 3.8 min Avg. Velocity =.69 fps, Avg. Travel Time= 1.2 min Peak Storage= 1, hrs Average Depth at Peak Storage=.28' Bank-Full Depth= 2.' Flow Area= 32. sf, Capacity= ' x 2.' deep channel, n=.22 Earth, clean & straight Side Slope Z-value= 4. '/' Top Width= 24.' Length= 42.' Slope=.48 '/' Inlet Invert= 192.', Outlet Invert= 19.' Reach RN1: Swale Area=1. ac Avg. Flow Depth=.28' Max Vel=1.8 fps n=.22 L=42.' S=.48 '/' Capacity=

128 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 39 Summary for Reach RW1: Thru North Wetlands Area =.8 ac,.% Impervious, Depth =.63" for 1 Year St event = hrs, Volume=.34 af hrs, Volume=.289 af, Atten= 9%, Lag= min Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Max. Velocity=.4 fps, Min. Travel Time= 8.4 min Avg. Velocity =.2 fps, Avg. Travel Time= 1,73.8 min Peak Storage= 7, hrs Average Depth at Peak Storage=.14' Bank-Full Depth= 2.' Flow Area= 14. sf, Capacity= ' x 2.' deep channel, n=.4 Sheet flow: Woods+light brush Side Slope Z-value= 2. '/' Top Width= 11.' Length= 1,.' Slope=.2 '/' Inlet Invert= 22.', Outlet Invert= 199.' Reach RW1: Thru North Wetlands Area=.8 ac Avg. Flow Depth=.14' Max Vel=.4 fps n=.4 L=1,.' S=.2 '/' Capacity= Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 4 Summary for Reach SR1: To East Wetlands Area = 8.3 ac, 16.67% Impervious, Depth = 1.17" for 1 Year St event = hrs, Volume= 8.3 af = hrs, Volume= 8.3 af, Atten= %, Lag= 3.2 min Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Max. Velocity= 4.43 fps, Min. Travel Time= 3.8 min Avg. Velocity = 1.14 fps, Avg. Travel Time= 14.6 min Peak Storage= 7, hrs Average Depth at Peak Storage=.61' Bank-Full Depth= 2.' Flow Area= 66. sf, Capacity= ' x 2.' deep channel, n=.3 Earth, grassed & winding Side Slope Z-value= 1. '/' Top Width= 63.' Length= 1,.' Slope=.33 '/' Inlet Invert= 229.', Outlet Invert= 196.' Reach SR1: To East Wetlands Area=8.3 ac Avg. Flow Depth=.61' Max Vel=4.43 fps n=.3 L=1,.' S=.33 '/' Capacity=611.72

129 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 41 Summary for Reach TB1: Trolley Brook Area = ac, 1.6% Impervious, Depth > 2.84" for 1 Year St event = 12. hrs, Volume= af = 12.6 hrs, Volume= af, Atten= %, Lag=.8 min Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Max. Velocity= 2.67 fps, Min. Travel Time= 1.1 min Avg. Velocity = 1.1 fps, Avg. Travel Time= 2. min Peak Storage= 2, hrs Average Depth at Peak Storage=.7' Bank-Full Depth= 6.' Flow Area= 198. sf, Capacity= 1, ' x 6.' deep channel, n=.3 Side Slope Z-value= 3. '/' Top Width= 1.' Length= 18.' Slope=.6 '/' Inlet Invert= 188.', Outlet Invert= 187.' Reach TB1: Trolley Brook Area=191.6 ac Avg. Flow Depth=.7' Max Vel=2.67 fps n=.3 L=18.' S=.6 '/' Capacity=1, Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 42 Summary for Pond C: Inlet to Culvert [8] Hint: Peaked.83' above defined flood level [61] Hint: Exceeded Reach CB1 outlet invert 12.3 hrs [63] Warning: Exceeded Reach TB1 INLET depth by 12.3 hrs Area = 294. ac, 19.89% Impervious, Depth > 2.41" for 1 Year St event hrs, Volume= 8.93 af hrs, Volume= 8.93 af, Atten= %, Lag=. min Primary = hrs, Volume= 3.41 af Secondary = 12.3 hrs, Volume=.466 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= 12.3 hrs Flood Elev= 191.2' Device Routing Invert Outlet Devices #1 Primary 187.' 36." Round Culvert L= 82.' RCP, sq.cut end projecting, Ke=. Inlet / Outlet Invert= 187.' / 186.4' S=.73 '/' Cc=.9 n=.12, Flow Area= 7.7 sf #2 Secondary 191.2' 2.' long x 1.' breadth Broad-Crested Rectangular Weir Head (feet) Coef. (English) Primary OutFlow hrs HW=191.66' TW=191.29' (Dynamic Tailwater) 1=Culvert (Inlet Controls 2.92 fps) Secondary OutFlow 12.3 hrs HW=192.' TW=.' (Dynamic Tailwater) 2=Broad-Crested Rectangular Weir (Weir 2.4 fps)

130 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 43 Pond C: Inlet to Culvert Area=294. ac Peak Elev=192.3' Primary Secondary Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 44 Summary for Pond C1: DMH - 1 [8] Warning: Exceeded Pond C hrs ( af) [8] Warning: Exceeded Pond ND hrs ( af) Area = 31.9 ac, 21.46% Impervious, Depth > 2.1" for 1 Year St event = hrs, Volume=.643 af = hrs, Volume=.643 af, Atten= %, Lag=. min Primary = hrs, Volume=.636 af Secondary = hrs, Volume=.7 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 193.' Device Routing Invert Outlet Devices #1 Primary 186.' 36." Round Culvert L= 19.' RCP, groove end projecting, Ke=.2 Inlet / Outlet Invert= 186.' / 18.63' S=.34 '/' Cc=.9 n=.12, Flow Area= 7.7 sf #2 Secondary 192.' 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=191.3' TW=191.18' (Dynamic Tailwater) 1=Culvert (Outlet Controls 2.8 fps) Secondary OutFlow hrs HW=192.3' TW=.' (Dynamic Tailwater) 2=Orifice/Grate (Weir Controls 1.9 fps) Pond C1: DMH Area=31.9 ac Peak Elev=192.38' Primary Secondary

131 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 4 Summary for Pond C1: DMH-1 [8] Warning: Exceeded Pond C hrs ( af) Area = 32.9 ac, 22.79% Impervious, Depth > 2.17" for 1 Year St event = hrs, Volume= 8.42 af = hrs, Volume= 8.42 af, Atten= %, Lag=. min Primary = hrs, Volume= 8.42 af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 188.' Device Routing Invert Outlet Devices #1 Primary 179.' 48." W x 44." H Box Culvert L= 19.' RCP, groove end w/headwall, Ke=.2 Inlet / Outlet Invert= 179.' / 177.9' S=.6 '/' Cc=.9 n=.2, Flow Area= sf #2 Secondary 188.' 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=186.91' TW=186.6' (Dynamic Tailwater) 1=Culvert (Outlet Controls 3.31 fps) Secondary OutFlow hrs HW=179.1' TW=.' (Dynamic Tailwater) 2=Orifice/Grate ( Controls. ) Pond C1: DMH-1 Primary Secondary Area=32.9 ac Peak Elev=187.4' Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 46 Summary for Pond C11: DMH-11 [8] Warning: Exceeded Pond C1 12. hrs ( af) Area = 32.9 ac, 22.79% Impervious, Depth > 2.17" for 1 Year St event = hrs, Volume= 8.42 af = hrs, Volume= 8.42 af, Atten= %, Lag=. min Primary = hrs, Volume= 8.42 af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 187.' Device Routing Invert Outlet Devices #1 Primary 178.' 36." Round Culvert L= 87.' RCP, groove end w/headwall, Ke=.2 Inlet / Outlet Invert= 178.' / 177.6' S=.46 '/' Cc=.9 n=.12, Flow Area= 7.7 sf #2 Secondary 187.' 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=186.6' TW=184.61' (Dynamic Tailwater) 1=Culvert (Inlet Controls 7.24 fps) Secondary OutFlow hrs HW=178.3' TW=.' (Dynamic Tailwater) 2=Orifice/Grate ( Controls. ) Pond C11: DMH-11 Primary Secondary Area=32.9 ac Peak Elev=186.83'

132 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 47 Summary for Pond C12: DMH-12 Area = 32.9 ac, 22.79% Impervious, Depth > 2.17" for 1 Year St event = hrs, Volume= 8.42 af = hrs, Volume= 8.42 af, Atten= %, Lag=. min Primary = hrs, Volume= 8.42 af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 18.' Device Routing Invert Outlet Devices #1 Primary 177.' 36." Round Culvert L= 49.' RCP, groove end w/headwall, Ke=.2 Inlet / Outlet Invert= 177.' / 177.4' S=.2 '/' Cc=.9 n=.2, Flow Area= 7.7 sf #2 Secondary 18.' 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=184.61' TW=181.76' (Dynamic Tailwater) 1=Culvert (Outlet Controls 8.4 fps) Secondary OutFlow hrs HW=177.4' TW=.' (Dynamic Tailwater) 2=Orifice/Grate ( Controls. ) Pond C12: DMH-12 Primary Secondary Area=32.9 ac Peak Elev=184.74' Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 48 Summary for Pond C13: DMH-13 Area = ac, 22.9% Impervious, Depth > 2.18" for 1 Year St event = hrs, Volume= 8.31 af = hrs, Volume= 8.31 af, Atten= %, Lag=. min Primary = hrs, Volume= 8.31 af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 18.' Device Routing Invert Outlet Devices #1 Primary 177.4' 48." W x 44." H Box Culvert L= 137.' RCP, groove end w/headwall, Ke=.2 Inlet / Outlet Invert= 177.4' / 177.3' S=.7 '/' Cc=.9 n=.2, Flow Area= sf #2 Secondary 18.' 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=181.76' TW=.' (Dynamic Tailwater) 1=Culvert (Barrel Controls 4.99 fps) Secondary OutFlow hrs HW=177.41' TW=.' (Dynamic Tailwater) 2=Orifice/Grate ( Controls. ) Pond C13: DMH-13 Primary Secondary Area=321.7 ac Peak Elev=181.82'

133 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 49 Summary for Pond C2: DMH-2 [8] Hint: Peaked.49' above defined flood level Area = 31.9 ac, 21.46% Impervious, Depth > 2.1" for 1 Year St event = hrs, Volume=.636 af = hrs, Volume=.636 af, Atten= %, Lag=. min Primary = hrs, Volume=.6 af Secondary = hrs, Volume=.1 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 191.1' Device Routing Invert Outlet Devices #1 Primary 18.8' 36." Round Culvert L= 26.' CPP, square edge headwall, Ke=. Inlet / Outlet Invert= 18.4' / 18.8' S= -.16 '/' Cc=.9 n=.12, Flow Area= 7.7 sf #2 Secondary 191.1' 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=191.17' TW=189.88' (Dynamic Tailwater) 1=Culvert (Outlet Controls fps) Secondary OutFlow hrs HW=191.8' TW=.' (Dynamic Tailwater) 2=Orifice/Grate (Weir Controls 2.26 fps) Pond C2: DMH Area=31.9 ac Peak Elev=191.9' Primary Secondary Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page Summary for Pond C3: DMH-3 [8] Hint: Peaked.3' above defined flood level Area = 31.9 ac, 21.46% Impervious, Depth > 2.1" for 1 Year St event = hrs, Volume=.6 af = hrs, Volume=.6 af, Atten= %, Lag=. min Primary = hrs, Volume=.8 af Secondary = hrs, Volume=.24 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 19.2' Device Routing Invert Outlet Devices #1 Primary 18.6' 36." Round Culvert L= 18.6' RCP, groove end w/headwall, Ke=.2 Inlet / Outlet Invert=.' / 18.6' S= -1. '/' Cc=.9 n=.12, Flow Area= 7.7 sf #2 Secondary 19.2' 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=189.88' TW=188.76' (Dynamic Tailwater) 1=Culvert (Outlet Controls fps) Secondary OutFlow hrs HW=19.4' TW=.' (Dynamic Tailwater) 2=Orifice/Grate (Weir Controls 1.92 fps) Pond C3: DMH Area=31.9 ac Peak Elev=19.' Primary Secondary

134 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 1 Summary for Pond C4: DMH4 Area = ac, 21.7% Impervious, Depth > 2.13" for 1 Year St event = hrs, Volume=.978 af = hrs, Volume=.978 af, Atten= %, Lag=. min Primary = hrs, Volume=.978 af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 191.7' Device Routing Invert Outlet Devices #1 Primary 18.' 48." Round Culvert L= 176.' RCP, groove end w/headwall, Ke=.2 Inlet / Outlet Invert= 18.' / 18.1' S=.23 '/' Cc=.9 n=.13, Flow Area= 12.7 sf #2 Secondary 191.7' 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=188.76' TW=188.31' (Dynamic Tailwater) 1=Culvert (Outlet Controls 3.89 fps) Secondary OutFlow hrs HW=18.3' TW=.' (Dynamic Tailwater) 2=Orifice/Grate ( Controls. ) Pond C4: DMH Area=314.7 ac Peak Elev=19.8' Primary Secondary Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 2 Summary for Pond C: DMH- [8] Warning: Exceeded Pond C hrs ( af) Area = ac, 21.7% Impervious, Depth > 2.13" for 1 Year St event = hrs, Volume=.978 af = hrs, Volume=.978 af, Atten= %, Lag=. min Primary = hrs, Volume=.978 af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 19.9' Device Routing Invert Outlet Devices #1 Primary 18.' 48." Round Culvert L= 128.' RCP, groove end w/headwall, Ke=.2 Inlet / Outlet Invert= 18.' / 184.6' S=.31 '/' Cc=.9 n=.12, Flow Area= 12.7 sf #2 Secondary 191.3' 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=188.31' TW=187.63' (Dynamic Tailwater) 1=Culvert (Outlet Controls fps) Secondary OutFlow hrs HW=18.3' TW=.' (Dynamic Tailwater) 2=Orifice/Grate ( Controls. ) Pond C: DMH Area=314.7 ac Peak Elev=189.8' Primary Secondary

135 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 3 Summary for Pond C6: DMH-6 [8] Warning: Exceeded Pond C 12.1 hrs ( af) Area = ac, 21.7% Impervious, Depth > 2.13" for 1 Year St event = hrs, Volume=.978 af = hrs, Volume=.978 af, Atten= %, Lag=. min Primary = hrs, Volume=.978 af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 19.9' Device Routing Invert Outlet Devices #1 Primary 184.' 48." Round Culvert L= 164.' RCP, groove end w/headwall, Ke=.2 Inlet / Outlet Invert= 184.' / 182.6' S=.116 '/' Cc=.9 n=.13, Flow Area= 12.7 sf #2 Secondary 19.9' 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=187.63' TW=186.38' (Dynamic Tailwater) 1=Culvert (Outlet Controls 6.49 fps) Secondary OutFlow hrs HW=184.2' TW=.' (Dynamic Tailwater) 2=Orifice/Grate ( Controls. ) Pond C6: DMH Area=314.7 ac Peak Elev=189.77' Primary Secondary Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 4 Summary for Pond C6a: CB [8] Hint: Peaked.' above defined flood level [8] Warning: Exceeded Pond C hrs ( af) Area = 317. ac, 22.13% Impervious, Depth > 2.1" for 1 Year St event = hrs, Volume= af = hrs, Volume= af, Atten= %, Lag=. min Primary = hrs, Volume= 6.96 af Secondary = hrs, Volume=.22 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 189.' Device Routing Invert Outlet Devices #1 Primary 182.6' 48." Round Culvert L= 6.' RCP, groove end w/headwall, Ke=.2 Inlet / Outlet Invert= 182.' / 182.6' S= -.18 '/' Cc=.9 n=.13, Flow Area= 12.7 sf #2 Secondary 189.' 24." x 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=187.' TW=187.27' (Dynamic Tailwater) 1=Culvert ( Controls. ) Secondary OutFlow hrs HW=188.66' TW=.' (Dynamic Tailwater) 2=Orifice/Grate ( Controls. ) Pond C6a: CB Area=317. ac Peak Elev=189.' Primary Secondary

136 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page Summary for Pond C7: DMH-7 [8] Warning: Exceeded Pond C6a hrs ( af) Area = 317. ac, 22.13% Impervious, Depth > 2.1" for 1 Year St event = hrs, Volume= 6.96 af = hrs, Volume= 6.96 af, Atten= %, Lag=. min Primary = hrs, Volume= 6.96 af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= 12.2 hrs Flood Elev= 194.' Device Routing Invert Outlet Devices #1 Primary 182.' 48." Round Culvert L= 132.' RCP, groove end w/headwall, Ke=.2 Inlet / Outlet Invert= 182.' / 181.' S=.76 '/' Cc=.9 n=.13, Flow Area= 12.7 sf #2 Secondary 191.' 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=187.27' TW=187.39' (Dynamic Tailwater) 1=Culvert ( Controls. ) Secondary OutFlow hrs HW=182.2' TW=.' (Dynamic Tailwater) 2=Orifice/Grate ( Controls. ) Pond C7: DMH Area=317. ac Peak Elev=189.22' Primary Secondary Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 6 Summary for Pond C8: DMH-8 [8] Warning: Exceeded Pond C hrs ( af) Area = 317. ac, 22.13% Impervious, Depth > 2.1" for 1 Year St event = hrs, Volume= 6.96 af = hrs, Volume= 6.96 af, Atten= %, Lag=. min Primary = hrs, Volume= 6.96 af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= 12.2 hrs Flood Elev= 191.' Device Routing Invert Outlet Devices #1 Primary 18.8' 48." W x 44." H Box Culvert L= 219.' RCP, groove end w/headwall, Ke=.2 Inlet / Outlet Invert= 18.8' / 179.1' S=.78 '/' Cc=.9 n=.2, Flow Area= sf #2 Secondary 191.' 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=187.39' TW=186.3' (Dynamic Tailwater) 1=Culvert (Outlet Controls 4. fps) Secondary OutFlow hrs HW=18.81' TW=.' (Dynamic Tailwater) 2=Orifice/Grate ( Controls. ) Pond C8: DMH Area=317. ac Peak Elev=189.21' Primary Secondary

137 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 7 Summary for Pond C9: DMH-9 [8] Warning: Exceeded Pond C hrs ( af) Area = 32.9 ac, 22.79% Impervious, Depth > 2.17" for 1 Year St event = hrs, Volume= 8.42 af = hrs, Volume= 8.42 af, Atten= %, Lag=. min Primary = hrs, Volume= 8.42 af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= 12.1 hrs Flood Elev= 188.' Device Routing Invert Outlet Devices #1 Primary 179.3' 48." W x 44." H Box Culvert L= 88.' RCP, groove end w/headwall, Ke=.2 Inlet / Outlet Invert= 179.3' / 179.' S=.34 '/' Cc=.9 n=.2, Flow Area= sf #2 Secondary 188.' 24." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads Primary OutFlow hrs HW=187.83' TW=186.91' (Dynamic Tailwater) 1=Culvert (Outlet Controls 4.1 fps) Secondary OutFlow hrs HW=179.31' TW=.' (Dynamic Tailwater) 2=Orifice/Grate ( Controls. ) Pond C9: DMH-9 Primary Secondary Area=32.9 ac Peak Elev=188.3' Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 8 Summary for Pond DRP: RDP Area = 3.7 ac, 42.2% Impervious, Depth = 3.21" for 1 Year St event = hrs, Volume= 8.2 af = hrs, Volume= 8.2 af, Atten= 1%, Lag= 21.3 min Discarded = hrs, Volume= af Primary = hrs, Volume= af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Surf.Area= 37,6 sf Storage= 11,663 cf Plug-Flow detention time= (not calculated: outflow precedes inflow) Center-of-Mass det. time=.6 min ( ) Volume Invert Avail.Storage Storage Description #1 268.' 273,27 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) , ,624 6,14 6, ,29 1,13 21, ,12 3,842 2, ,32 119, , ,312 89, , , 38,92 273,27 Device Routing Invert Outlet Devices #1 Primary 26.9' 24." Round Culvert L= 7.' CPP, square edge headwall, Ke=. Inlet / Outlet Invert= 26.9' / 26.' S=.12 '/' Cc=.9 n=.12, Flow Area= 3.14 sf #2 Device ' 8." Vert. Orifice/Grate X 4. C=.6 #3 Device ' 48." x 48." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads #4 Primary 27.' 3." Round Culvert L= 7.' CPP, square edge headwall, Ke=. Inlet / Outlet Invert= 27.' / 269.8' S=.1 '/' Cc=.9 n=.12, Flow Area= 4.91 sf # Device 4 27.' 1." Vert. Orifice/Grate X 2. C=.6 #6 Device ' 1. deg x 3.' rise Sharp-Crested Vee/Trap Weir Cv= 2.49 (C= 3.11) #7 Device ' 48." x 48." Horiz. Orifice/Grate C=.6 Limited to weir flow at low heads #8 Secondary 276.' 3.' long x 2.' breadth Broad-Crested Rectangular Weir Head (feet) Coef. (English) #9 Discarded 268.' 2.41 in/hr Exfiltration over Surface area

138 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 9 Discarded OutFlow hrs HW=272.92' (Free Discharge) 9=Exfiltration (Exfiltration Controls 2.1 ) Primary OutFlow hrs HW=272.92' TW=2.8' (Dynamic Tailwater) 1=Culvert (Passes 13.8 of potential flow) 2=Orifice/Grate (Orifice Controls 9.37 fps) 3=Orifice/Grate ( Controls. ) 4=Culvert (Passes 22.4 of 2.13 potential flow) =Orifice/Grate (Orifice Controls 6.81 fps) 6=Sharp-Crested Vee/Trap Weir (Weir Controls 3.4 fps) 7=Orifice/Grate ( Controls. ) Secondary OutFlow hrs HW=268.' TW=248.98' (Dynamic Tailwater) 8=Broad-Crested Rectangular Weir ( Controls. ) Pond DRP: RDP Area=3.7 ac Peak Elev=272.92' Storage=11,663 cf Discarded Primary Secondary Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 6 Summary for Pond DS1: Lorraine Detention Area = 22.3 ac, 2.72% Impervious, Depth = 2.39" for 1 Year St event = hrs, Volume= 4.44 af = hrs, Volume= 4.44 af, Atten= 36%, Lag= 14.1 min Discarded hrs, Volume=.249 af Primary = hrs, Volume= af Secondary = hrs, Volume=.36 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Surf.Area= 8,27 sf Storage= 33,938 cf Plug-Flow detention time= 2.2 min calculated for 4.44 af (1% of inflow) Center-of-Mass det. time= 2.2 min ( ) Volume Invert Avail.Storage Storage Description #1 27.' 9,638 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) ,7 1,388 1, , 7,7 9, , 27, 36, , 23, 9, ' Device #1 #2 #3 Coef. (English) Head (feet) Outlet Devices 12." Round Culvert L= 1.' RCP, square edge headwall, Ke= Inlet / Outlet Invert= 27.3' / 274.' S=.13 '/' Cc=.9 n=.13, Flow Area=.79 sf 1." Round Culvert L= 1.' RCP, square edge headwall, Ke= Inlet / Outlet Invert= ' / 276.' S=.163 '/' Cc=.9 n=.13, Flow Area= 1.23 sf 12." Round Culvert L= 2.' RCP, square edge headwall, Ke= Inlet / Outlet Invert= 277.2' / 277.' S=.26 '/' Cc=.9 n=.13, Flow Area=.79 sf Discarded OutFlow hrs HW=281.74' (Free Discharge) =Exfiltration (Exfiltration Controls.46 ) Primary OutFlow hrs HW=281.74' TW=229.' (Dynamic Tailwater) 1=Culvert (Barrel Controls 9.67 fps) 2=Culvert (Barrel Controls 8.68 fps) 3=Culvert (Inlet Controls 9.28 fps) Secondary OutFlow hrs HW=281.74' TW=233.36' (Dynamic Tailwater) 4=Broad-Crested Rectangular Weir (Weir Controls 1.22 fps)

139 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 61 Pond DS1: Lorraine Detention Area=22.3 ac Peak Elev=281.74' Storage=33,938 cf Discarded Primary Secondary Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 62 Summary for Pond DS2: Middle School Culvert Area = 63. ac, 1.24% Impervious, Depth =.8" for 1 Year St event = hrs, Volume= af = hrs, Volume= 4.14 af, Atten= 31%, Lag= 2.6 min Primary = hrs, Volume= 4.14 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Surf.Area=.77 ac Storage=.629 af Plug-Flow detention time= 2.1 min calculated for 4.14 af (98% of inflow) Center-of-Mass det. time= 42. min ( ) Volume Invert Avail.Storage Storage Description #1 232.' af Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (acres) (acre-feet) (acre-feet) Device Routing Invert Outlet Devices #1 Primary 233.' 36." Round Culvert L=.' RCP, square edge headwall, Ke=. Inlet / Outlet Invert= 233.' / 231.9' S=.22 '/' Cc=.9 n=.13, Flow Area= 7.7 sf Primary OutFlow hrs HW=234.43' TW=229.6' (Dynamic Tailwater) 1=Culvert (Inlet Controls 4.7 fps)

140 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 63 Pond DS2: Middle School Culvert Area=63. ac Peak Elev=234.43' Storage=.629 af 36." Round Culvert n=.13 L=.' S=.22 '/' Primary Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 64 Summary for Pond DS3: Nyanza South Area = 23.6 ac,.% Impervious, Depth = 1.41" for 1 Year St event = 12.8 hrs, Volume= 2.76 af = 12.9 hrs, Volume= 2.76 af, Atten= %, Lag=.8 min Discarded 12.9 hrs, Volume=.48 af Primary = 12.9 hrs, Volume= af Secondary = 12.9 hrs, Volume=.868 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= 12.9 hrs Surf.Area= 1,486 sf Storage= 1,414 cf Plug-Flow detention time= 3.1 min calculated for af (1% of inflow) Center-of-Mass det. time= 3.1 min ( ) Volume Invert Avail.Storage Storage Description #1 198.' 124,8 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) ,2 1,2 1, , 39,6 4, , 84, 124,8 Device Routing Invert Outlet Devices #1 Primary 198.6' 24." Round Culvert L= 33.' RCP, sq.cut end projecting, Ke=. Inlet / Outlet Invert= 198.6' / 197.4' S=.36 '/' Cc=.9 n=.13, Flow Area= 3.14 sf #2 Secondary 199.1' 32." W x 22." H Box Culvert L=.' Box, headwall w/3 square edges, Ke=. Inlet / Outlet Invert= 199.1' / 197.9' S=.24 '/' Cc=.9 n=.2, Flow Area= 4.89 sf #3 Discarded 198.' 2.41 in/hr Exfiltration over Surface area Discarded OutFlow 12.9 hrs HW=2.16' (Free Discharge) 3=Exfiltration (Exfiltration Controls.8 ) Primary OutFlow 12.9 hrs HW=2.16' TW=192.47' (Dynamic Tailwater) 1=Culvert (Barrel Controls 4.46 fps) Secondary OutFlow 12.9 hrs HW=2.16' TW=192.99' (Dynamic Tailwater) 2=Culvert (Inlet Controls 3.3 fps)

141 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 6 Pond DS3: Nyanza South Area=23.6 ac Peak Elev=2.16' Storage=1,414 cf Discarded Primary Secondary Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 66 Summary for Pond DS4: East Wetlands Area = 12.8 ac, 16.99% Impervious, Depth > 2.1" for 1 Year St event = hrs, Volume= af, Incl. 2. Base Flow = hrs, Volume= 2.71 af, Atten= 68%, Lag= min Primary = hrs, Volume= 2.71 af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Starting Elev= 192.' Surf.Area=.44 ac Storage= 8.1 af Peak Elev= hrs Surf.Area= ac Storage= 14.4 af (6.3 af above start) Plug-Flow detention time= 1,348.8 min calculated for af (64% of inflow) Center-of-Mass det. time= min ( 1, ,93. ) Volume Invert Avail.Storage Storage Description # ' af Custom Stage Data (Prismatic) Listed below Elevation Surf.Area Inc.Store Cum.Store (feet) (acres) (acre-feet) (acre-feet) ' Device #1 #2 #3 Coef. (English) Head (feet) Outlet Devices 36." Round Culvert L= 7.' CPP, square edge headwall, Ke= Inlet / Outlet Invert= 191.3' / 19.4' S=.129 '/' Cc=.9 n=.12, Flow Area= 7.7 sf 6.1' long x 3.' rise Sharp-Crested Rectangular Weir 2 End Contraction(s) 12." Round Culvert L= 3.' RCP, sq.cut end projecting, Ke= Inlet / Outlet Invert= 192.6' / 192.' S=.33 '/' Cc=.9 n=.12, Flow Area=.79 sf Primary OutFlow hrs HW=193.43' TW=191.93' (Dynamic Tailwater) 1=Culvert (Passes of potential flow) 2=Sharp-Crested Rectangular Weir (Weir Controls 3.16 fps) 3=Culvert (Barrel Controls 3.2 fps) Secondary OutFlow hrs HW=192.' TW=189.78' (Dynamic Tailwater) 4=Broad-Crested Rectangular Weir ( Controls. )

142 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 67 Pond DS4: East Wetlands Primary Secondary Area=12.8 ac Peak Elev=193.43' Storage=14.4 af Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 68 Summary for Pond DS: Settle Ponds Area = 2.2 ac, 9.9% Impervious, Depth = 1.31" for 1 Year St event = hrs, Volume=.24 af hrs, Volume=. af, Atten= 1%, Lag=. min Primary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Surf.Area=.27 ac Storage=.24 af Plug-Flow detention time= (not calculated: initial storage exceeds outflow) Center-of-Mass det. time= (not calculated: no outflow) Volume Invert Avail.Storage Storage Description #1 21.' 1.92 af Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (acres) (acre-feet) (acre-feet) Device Routing Invert Outlet Devices #1 Primary 219.7'.' long x 2.' breadth Broad-Crested Rectangular Weir Head (feet) Coef. (English) Primary OutFlow hrs HW=21.' TW=189.78' (Dynamic Tailwater) 1=Broad-Crested Rectangular Weir ( Controls. ) Pond DS: Settle Ponds Primary Area=2.2 ac Peak Elev=216.' Storage=.24 af 1.

143 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 69 Summary for Pond DS6: Trolley Brook Area = ac, 1.6% Impervious, Depth > 2.84" for 1 Year St event = hrs, Volume= 4.48 af, Incl. 2. Base Flow = 12. hrs, Volume= af, Atten= 22%, Lag= 19.3 min Primary = 12. hrs, Volume= af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= 12. hrs Surf.Area= 21,2 sf Storage= 2,418 cf Flood Elev= 19.8' Surf.Area= 98,3 sf Storage= 218,928 cf Plug-Flow detention time= 6. min calculated for af (1% of inflow) Center-of-Mass det. time= 4.2 min ( 1, ,811.8 ) Volume Invert Avail.Storage Storage Description # ' 48,63 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) , 4,12 4, , 8,7 13, , 226, 239, , 111, 3, , 13, 48, ' Device #1 Coef. (English) Head (feet) Outlet Devices 24." Round Culvert X 2. L= 7.' CPP, projecting, no headwall, Ke=.9 Inlet / Outlet Invert= 189.7' / 189.4' S=.4 '/' Cc=.9 n=.12, Flow Area= 3.14 sf Primary OutFlow 12. hrs HW=192.47' TW=188.7' (Dynamic Tailwater) 1=Culvert (Inlet Controls fps) Secondary OutFlow hrs HW=189.78' TW=188.' (Dynamic Tailwater) 2=Broad-Crested Rectangular Weir ( Controls. ) Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 7 Pond DS6: Trolley Brook Area=191.6 ac Peak Elev=192.47' Storage=2,418 cf Primary Secondary

144 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 71 Summary for Pond DW1: Nyanza-W Ret/Det Area = 13.7 ac, 7.3% Impervious, Depth = 1.9" for 1 Year St event = hrs, Volume= af hrs, Volume= 1.81 af, Atten= 97%, Lag= min Primary hrs, Volume= 1.81 af Secondary hrs, Volume=. af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Surf.Area= 4,423 sf Storage= 77,12 cf Plug-Flow detention time= 1,33. min calculated for 1.81 af (% of inflow) Center-of-Mass det. time= 9.6 min ( 1, ) Volume Invert Avail.Storage Storage Description #1 199.' 299,7 cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) , 2. 2, 17,7 17, , 67, 84, , 96, 18, , 119, 299,7 24.7' Device #1 Coef. (English) Head (feet) Limited to weir flow at low heads Outlet Devices 24." Round Culvert L= 2.' CPP, square edge headwall, Ke= Inlet / Outlet Invert= 199.' / 196.2' S=.137 '/' Cc=.9 n=.12, Flow Area= 3.14 sf Primary OutFlow hrs HW=21.81' TW=197.7' (Dynamic Tailwater) 1=Culvert (Passes.48 of 2.38 potential flow) 2=Orifice/Grate (Orifice 4.3 fps) Secondary OutFlow hrs HW=199.' TW=196.' (Dynamic Tailwater) 3=Broad-Crested Rectangular Weir ( Controls. ) Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 72 Pond DW1: Nyanza-W Ret/Det Area=13.7 ac Peak Elev=21.81' Storage=77,12 cf Primary Secondary

145 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 73 Summary for Pond DW2: MBTA Culverts Area = 33.2 ac, 38.86% Impervious, Depth = 2.4" for 1 Year St event = hrs, Volume= 7.21 af = hrs, Volume= 7.21 af, Atten= %, Lag=. min Primary = hrs, Volume= 7.21 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Flood Elev= 24.' Device Routing Invert Outlet Devices #1 Primary ' 36." Round Culvert L=.' RCP, groove end projecting, Ke=.2 Inlet / Outlet Invert= ' / ' S=.6 '/' Cc=.9 n=.13, Flow Area= 7.7 sf #2 Primary 249.2' 36." Round Culvert L=.' RCP, groove end projecting, Ke=.2 Inlet / Outlet Invert= 249.2' / ' S=.94 '/' Cc=.9 n=.13, Flow Area= 7.7 sf Primary OutFlow hrs HW=2.8' TW=197.39' (Dynamic Tailwater) 1=Culvert (Inlet Controls fps) 2=Culvert (Inlet Controls 4.92 fps) Pond DW2: MBTA Culverts Primary Area=33.2 ac Peak Elev=2.8' Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 74 Summary for Pond DW3: MBTA Detention Area = 4. ac,1.% Impervious, Depth =.1" for 1 Year St event = hrs, Volume= 1.88 af = hrs, Volume= af, Atten= 81%, Lag= 28.7 min Primary = hrs, Volume= af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Surf.Area=.4 ac Storage=.927 af Plug-Flow detention time= min calculated for af (99% of inflow) Center-of-Mass det. time= min ( 1, ) Volume Invert Avail.Storage Storage Description #1 197.' 2.47 af Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (acres) (acre-feet) (acre-feet) ' Device #1 Coef. (English) Head (feet) Outlet Devices Custom Weir/Orifice, Cv= 2.62 (C= 3.28) Head (feet). 4. Width (feet).. Primary OutFlow hrs HW=199.28' TW=197.36' (Dynamic Tailwater) 1=Custom Weir/Orifice (Weir Controls 4.37 fps) 2=Broad-Crested Rectangular Weir ( Controls. )

146 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 7 Pond DW3: MBTA Detention Area=4. ac Peak Elev=199.28' Storage=.927 af Primary Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 76 Summary for Pond DW4: No. Wetlands Area = 89.2 ac, 21.86% Impervious, Depth > 1.87" for 1 Year St event = 12.2 hrs, Volume= af = hrs, Volume= af, Atten= 76%, Lag= 14.4 min Primary = hrs, Volume= af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= hrs Surf.Area=.362 ac Storage= 6.3 af Plug-Flow detention time= 438. min calculated for af (74% of inflow) Center-of-Mass det. time= min ( 1, ) Volume Invert Avail.Storage Storage Description #1 196.' 19.3 af Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (acres) (acre-feet) (acre-feet) Device Routing Invert Outlet Devices #1 Primary 197.' 12.' long x.' breadth Broad-Crested Rectangular Weir Head (feet) Coef. (English) Primary OutFlow hrs HW=198.1' TW=196.8' (Dynamic Tailwater) 1=Broad-Crested Rectangular Weir (Weir Controls 2.9 fps)

147 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 77 Pond DW4: No. Wetlands Primary Area=89.2 ac Peak Elev=198.1' Storage=6.3 af Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 78 Summary for Pond ND1: NW MBTA Wetlands Area = 8.3 ac, 37.98% Impervious, Depth = 1.31" for 1 Year St event = 12.3 hrs, Volume=.9 af 1.78 hrs, Volume=.791 af, Atten= 91%, Lag= 28.4 min Discarded 1.78 hrs, Volume=.32 af Primary 1.78 hrs, Volume=.29 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= 1.78 hrs Surf.Area= 32,76 sf Storage= 23,92 cf Plug-Flow detention time= min calculated for.791 af (87% of inflow) Center-of-Mass det. time= 88.6 min ( 1, ) Volume Invert Avail.Storage Storage Description #1 194.' 69, cf Custom Stage Data (Prismatic) Listed below (Recalc) Elevation Surf.Area Inc.Store Cum.Store (feet) (sq-ft) (cubic-feet) (cubic-feet) , , 69, 69, Device Routing Invert Outlet Devices #1 Discarded 194.' 1.2 in/hr Exfiltration over Horizontal area from 194.' - 19.' Excluded Horizontal area = 2, sf #2 Primary 194.7'.' long x 2.' breadth Broad-Crested Rectangular Weir Head (feet) Coef. (English) Discarded OutFlow 1.78 hrs HW=194.82' (Free Discharge) 1=Exfiltration (Exfiltration Controls.18 ) Primary OutFlow 1.78 hrs HW=194.82' TW=192.1' (Dynamic Tailwater) 2=Broad-Crested Rectangular Weir (Weir fps)

148 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 79 Pond ND1: NW MBTA Wetlands Area=8.3 ac Peak Elev=194.82' Storage=23,92 cf Discarded Primary Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=.2" Printed 6/17/216 Page 8 Summary for Pond ND2: 24" RCP Pipe [7] Hint: Peaked at ' (Flood elevation advised) [63] Warning: Exceeded Reach RN1 INLET depth 12.1 hrs Area = 13.4 ac, 4.31% Impervious, Depth = 1.17" for 1 Year St event = hrs, Volume= 1.32 af = hrs, Volume= 1.32 af, Atten= %, Lag=. min Primary = hrs, Volume= 1.32 af Routing by Dyn-Stor-Ind method, Time Span=.-72. hrs, dt=.1 hrs / 3 Peak Elev= 12.1 hrs Device Routing Invert Outlet Devices #1 Primary 19.' 24." Round Culvert L= 33.' RCP, groove end projecting, Ke=.2 Inlet / Outlet Invert= 19.' / 189.' S=.3 '/' Cc=.9 n=.13, Flow Area= 3.14 sf Primary OutFlow hrs HW=192.89' TW=191.82' (Dynamic Tailwater) 1=Culvert (Outlet Controls 3.9 fps) Pond ND2: 24" RCP Pipe Primary Area=13.4 ac Peak Elev=193.27' 24." Round Culvert n=.13 L=33.' S=.3 '/' 2

149 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=2.73" Printed 6/17/216 Page 81 Time span=.-72. hrs, dt=.1 hrs, 721 points x 3 Runoff by SCS TR-2 method, UH=SCS, Weighted-CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment N1: NW MBTA Runoff Area=8.3 ac 37.98% Impervious Runoff Depth=.19" Flow Length=7' Tc=19. min CN=8 Runoff= af Subcatchment N2: Metcalf Ave Runoff Area=2.2 ac 4.91% Impervious Runoff Depth=.61" Tc=1. min CN=71 Runoff= af Subcatchment N3: Foster Ave Runoff Area=2.9 ac 9.3% Impervious Runoff Depth=.74" Tc=1. min CN=74 Runoff= af Subcatchment N4: 6 Pleasant Runoff Area=3. ac 62.4% Impervious Runoff Depth=.84" Tc=1. min CN=76 Runoff= af Subcatchment N: Tilton Ave Runoff Area=3.8 ac 3.% Impervious Runoff Depth=.17" Tc=1. min CN=7 Runoff=.21.4 af Subcatchment N6: Police/Fire Runoff Area=2.8 ac 8.% Impervious Runoff Depth=1.66" Tc=1. min CN=89 Runoff= af Subcatchment N7: Downtown Runoff Area=3.4 ac 8.% Impervious Runoff Depth=1.66" Tc=1. min CN=89 Runoff= af Subcatchment N8: Library Runoff Area=.8 ac 8.% Impervious Runoff Depth=1.66" Tc=1. min CN=89 Runoff= af Subcatchment S1: Lorraine Dr Runoff Area=22.3 ac 2.72% Impervious Runoff Depth=.6" Flow Length=2,' Tc=16.3 min CN=72 Runoff= af Subcatchment S2: Middle School Runoff Area=63. ac 1.24% Impervious Runoff Depth=." Flow Length=2,3' Tc=4.2 min CN= Runoff= af Subcatchment S3: MBTA RD. CB-3 Runoff Area=6.6 ac.% Impervious Runoff Depth=.13" Flow Length=1,98' Tc=38.8 min CN= Runoff= af Subcatchment S4: South Wetlands Runoff Area=22.4 ac 4.46% Impervious Runoff Depth=." Flow Length=1,8' Tc=41.2 min CN=33 Runoff=.. af Subcatchment S: SE Wetlands Runoff Area=17. ac 2.94% Impervious Runoff Depth=." Flow Length=9' Tc=37.7 min CN=38 Runoff=.. af Subcatchment S6: Nyanza south Runoff Area=17. ac.% Impervious Runoff Depth=.27" Flow Length=1,3' Tc=36.4 min CN=61 Runoff= af Subcatchment S7: East Wetlands Runoff Area=28.1 ac 36.44% Impervious Runoff Depth=.17" Flow Length=8' Tc=32.7 min CN=7 Runoff= af Subcatchment S8: Nyanza east Runoff Area=13. ac 29.3% Impervious Runoff Depth=.84" Flow Length=9' Tc=1.3 min CN=76 Runoff= af Subcatchment S9: Settle Ponds Runoff Area=2.2 ac 9.9% Impervious Runoff Depth=.19" Flow Length=1' Tc=13.8 min CN=8 Runoff=.1.3 af Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=2.73" Printed 6/17/216 Page 82 Subcatchment W1: MBTA CB-2-Direct Runoff Area=2. ac.% Impervious Runoff Depth=." Flow Length=1,31' Tc=19.4 min CN=37 Runoff=.. af Subcatchment W2: RDAP Development Runoff Area=3.7 ac 42.2% Impervious Runoff Depth=1.11" Tc=2.7 min CN=81 Runoff= af Subcatchment W3: MBTA CB-1 Runoff Area=.8 ac.% Impervious Runoff Depth=.2" Flow Length=' Tc=1.4 min CN=47 Runoff=.1.9 af Subcatchment W4: MBTA Park Runoff Area=4. ac 1.% Impervious Runoff Depth=2." Tc=1. min CN=98 Runoff= af Subcatchment W: Nyanza West Runoff Area=13.7 ac 7.3% Impervious Runoff Depth=.42" Flow Length=9' Slope=.1 '/' Tc=26.3 min CN=66 Runoff= af Subcatchment W6: No. Wetlands Runoff Area=32. ac 3.44% Impervious Runoff Depth=.22" Flow Length=1,' Tc=2.1 min CN=9 Runoff= af Subcatchment W7: Chemical Brook Runoff Area=9.9 ac 66.91% Impervious Runoff Depth=.94" Flow Length=1,8' Tc=26.9 min CN=78 Runoff= af Subcatchment W8: Megunko Road Runoff Area=3.3 ac 72.% Impervious Runoff Depth=1.11" Flow Length=9' Slope=. '/' Tc=17.3 min CN=81 Runoff=3..3 af Reach CB1: Chemical Brook Avg. Flow Depth=.6' Max Vel=1.83 fps = af n=.22 L=1,.' S=.23 '/' Capacity=64.47 = af Reach FL: Flooding =.. af =.. af Reach RC1: To Sudbury River = af = af Reach RN1: Swale Avg. Flow Depth=.11' Max Vel=1.4 fps = af n=.22 L=42.' S=.48 '/' Capacity= = af Reach RW1: Thru North Wetlands Avg. Flow Depth=.1' Max Vel=.1 fps =.1.9 af n=.4 L=1,.' S=.2 '/' Capacity=27.3 =..7 af Reach SR1: To East Wetlands Avg. Flow Depth=.29' Max Vel=2.87 fps = af n=.3 L=1,.' S=.33 '/' Capacity= = af Reach TB1: Trolley Brook Avg. Flow Depth=.39' Max Vel=1.88 fps = af n=.3 L=18.' S=.6 '/' Capacity=1, = af Pond C: Inlet to Culvert Peak Elev=189.' = af Primary= af Secondary=.. af = af Pond C1: DMH - 1 Peak Elev=189.2' = af Primary= af Secondary=.. af = af Pond C1: DMH-1 Peak Elev=182.4' = af Primary= af Secondary=.. af = af

150 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=2.73" Printed 6/17/216 Page 83 Pond C11: DMH-11 Peak Elev=181.3' = af Primary= af Secondary=.. af = af Pond C12: DMH-12 Peak Elev=18.83' = af Primary= af Secondary=.. af = af Pond C13: DMH-13 Peak Elev=18.11' = af Primary= af Secondary=.. af = af Pond C2: DMH-2 Peak Elev=188.63' = af Primary= af Secondary=.. af = af Pond C3: DMH-3 Peak Elev=188.8' = af Primary= af Secondary=.. af = af Pond C4: DMH4 Peak Elev=187.73' = af Primary= af Secondary=.. af = af Pond C: DMH- Peak Elev=187.3' = af Primary= af Secondary=.. af = af Pond C6: DMH-6 Peak Elev=186.28' = af Primary= af Secondary=.. af = af Pond C6a: CB Peak Elev=184.91' = af Primary= af Secondary=.. af = af Pond C7: DMH-7 Peak Elev=184.44' = af Primary= af Secondary=.. af = af Pond C8: DMH-8 Peak Elev=183.29' = af Primary= af Secondary=.. af = af Pond C9: DMH-9 Peak Elev=182.43' = af Primary= af Secondary=.. af = af Pond DRP: RDP Peak Elev=27.89' Storage=33,872 cf = af Discarded= af Primary= af Secondary=.. af = af Pond DS1: Lorraine Detention Peak Elev=277.9' Storage=8,884 cf = af Discarded= af Primary= af Secondary=.. af = af Pond DS2: Middle School Culvert Peak Elev=233.18' Storage=.11 af = af 36." Round Culvert n=.13 L=.' S=.22 '/' = af Pond DS3: Nyanza South Peak Elev=199.18' Storage=416 cf = af Discarded=.4.3 af Primary= af Secondary=.18.6 af = af Pond DS4: East Wetlands Peak Elev=192.82' Storage=1.287 af = af Primary= af Secondary=.. af = af Pond DS: Settle Ponds Peak Elev=21.67' Storage=.3 af =.1.3 af =.. af Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=2.73" Printed 6/17/216 Page 84 Pond DS6: Trolley Brook Peak Elev=191.1' Storage=4,42 cf = af Primary= af Secondary=.. af = af Pond DW1: Nyanza-W Ret/Det Peak Elev=2.13' Storage=2,97 cf = af Primary=.. af Secondary=.. af =.. af Pond DW2: MBTA Culverts Peak Elev=249.8' = af = af Pond DW3: MBTA Detention Peak Elev=198.48' Storage=.1 af = af = af Pond DW4: No. Wetlands Peak Elev=197.48' Storage=3.24 af = af =.. af Pond ND1: NW MBTA Wetlands Peak Elev=194.18' Storage=4,3 cf = af Discarded=.4.11 af Primary=.. af =.4.11 af Pond ND2: 24" RCP Pipe Peak Elev=19.86' = af 24." Round Culvert n=.13 L=33.' S=.3 '/' = af Total Runoff Area = ac Runoff Volume = af Average Runoff Depth =.41" 77.% Pervious = ac 22.9% Impervious = ac

151 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 2 Year St Rainfall=3.36" Printed 6/17/216 Page 8 Time span=.-72. hrs, dt=.1 hrs, 721 points x 3 Runoff by SCS TR-2 method, UH=SCS, Weighted-CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment N1: NW MBTA Runoff Area=8.3 ac 37.98% Impervious Runoff Depth=.4" Flow Length=7' Tc=19. min CN=8 Runoff= af Subcatchment N2: Metcalf Ave Runoff Area=2.2 ac 4.91% Impervious Runoff Depth=.98" Tc=1. min CN=71 Runoff= af Subcatchment N3: Foster Ave Runoff Area=2.9 ac 9.3% Impervious Runoff Depth=1.14" Tc=1. min CN=74 Runoff= af Subcatchment N4: 6 Pleasant Runoff Area=3. ac 62.4% Impervious Runoff Depth=1.26" Tc=1. min CN=76 Runoff= af Subcatchment N: Tilton Ave Runoff Area=3.8 ac 3.% Impervious Runoff Depth=.36" Tc=1. min CN=7 Runoff= af Subcatchment N6: Police/Fire Runoff Area=2.8 ac 8.% Impervious Runoff Depth=2.23" Tc=1. min CN=89 Runoff=6.3.2 af Subcatchment N7: Downtown Runoff Area=3.4 ac 8.% Impervious Runoff Depth=2.23" Tc=1. min CN=89 Runoff= af Subcatchment N8: Library Runoff Area=.8 ac 8.% Impervious Runoff Depth=2.23" Tc=1. min CN=89 Runoff= af Subcatchment S1: Lorraine Dr Runoff Area=22.3 ac 2.72% Impervious Runoff Depth=1.3" Flow Length=2,' Tc=16.3 min CN=72 Runoff= af Subcatchment S2: Middle School Runoff Area=63. ac 1.24% Impervious Runoff Depth=.16" Flow Length=2,3' Tc=4.2 min CN= Runoff=1.6.8 af Subcatchment S3: MBTA RD. CB-3 Runoff Area=6.6 ac.% Impervious Runoff Depth=.3" Flow Length=1,98' Tc=38.8 min CN= Runoff=.9.16 af Subcatchment S4: South Wetlands Runoff Area=22.4 ac 4.46% Impervious Runoff Depth=." Flow Length=1,8' Tc=41.2 min CN=33 Runoff=.. af Subcatchment S: SE Wetlands Runoff Area=17. ac 2.94% Impervious Runoff Depth=." Flow Length=9' Tc=37.7 min CN=38 Runoff=.1.1 af Subcatchment S6: Nyanza south Runoff Area=17. ac.% Impervious Runoff Depth=.1" Flow Length=1,3' Tc=36.4 min CN=61 Runoff= af Subcatchment S7: East Wetlands Runoff Area=28.1 ac 36.44% Impervious Runoff Depth=.36" Flow Length=8' Tc=32.7 min CN=7 Runoff= af Subcatchment S8: Nyanza east Runoff Area=13. ac 29.3% Impervious Runoff Depth=1.26" Flow Length=9' Tc=1.3 min CN=76 Runoff= af Subcatchment S9: Settle Ponds Runoff Area=2.2 ac 9.9% Impervious Runoff Depth=.4" Flow Length=1' Tc=13.8 min CN=8 Runoff=.4.73 af Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 2 Year St Rainfall=3.36" Printed 6/17/216 Page 86 Subcatchment W1: MBTA CB-2-Direct Runoff Area=2. ac.% Impervious Runoff Depth=." Flow Length=1,31' Tc=19.4 min CN=37 Runoff=.. af Subcatchment W2: RDAP Development Runoff Area=3.7 ac 42.2% Impervious Runoff Depth=1.6" Tc=2.7 min CN=81 Runoff= af Subcatchment W3: MBTA CB-1 Runoff Area=.8 ac.% Impervious Runoff Depth=.1" Flow Length=' Tc=1.4 min CN=47 Runoff=.8.48 af Subcatchment W4: MBTA Park Runoff Area=4. ac 1.% Impervious Runoff Depth=3.13" Tc=1. min CN=98 Runoff= af Subcatchment W: Nyanza West Runoff Area=13.7 ac 7.3% Impervious Runoff Depth=.73" Flow Length=9' Slope=.1 '/' Tc=26.3 min CN=66 Runoff= af Subcatchment W6: No. Wetlands Runoff Area=32. ac 3.44% Impervious Runoff Depth=.44" Flow Length=1,' Tc=2.1 min CN=9 Runoff= af Subcatchment W7: Chemical Brook Runoff Area=9.9 ac 66.91% Impervious Runoff Depth=1.39" Flow Length=1,8' Tc=26.9 min CN=78 Runoff= af Subcatchment W8: Megunko Road Runoff Area=3.3 ac 72.% Impervious Runoff Depth=1.6" Flow Length=9' Slope=. '/' Tc=17.3 min CN=81 Runoff= af Reach CB1: Chemical Brook Avg. Flow Depth=.7' Max Vel=2.8 fps = af n=.22 L=1,.' S=.23 '/' Capacity=64.47 = af Reach FL: Flooding =.77.8 af =.77.8 af Reach RC1: To Sudbury River = af = af Reach RN1: Swale Avg. Flow Depth=.16' Max Vel=1.3 fps = af n=.22 L=42.' S=.48 '/' Capacity= = af Reach RW1: Thru North Wetlands Avg. Flow Depth=.3' Max Vel=.2 fps =.8.48 af n=.4 L=1,.' S=.2 '/' Capacity=27.3 =.2.39 af Reach SR1: To East Wetlands Avg. Flow Depth=.4' Max Vel=3.47 fps = af n=.3 L=1,.' S=.33 '/' Capacity= = af Reach TB1: Trolley Brook Avg. Flow Depth=.48' Max Vel=2.13 fps = af n=.3 L=18.' S=.6 '/' Capacity=1, = af Pond C: Inlet to Culvert Peak Elev=191.2' = af Primary= af Secondary=.77.8 af = af Pond C1: DMH - 1 Peak Elev=19.67' = af Primary= af Secondary=.. af = af Pond C1: DMH-1 Peak Elev=183.6' = af Primary= af Secondary=.. af = af

152 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 2 Year St Rainfall=3.36" Printed 6/17/216 Page 87 Pond C11: DMH-11 Peak Elev=183.13' = af Primary= af Secondary=.. af = af Pond C12: DMH-12 Peak Elev=182.16' = af Primary= af Secondary=.. af = af Pond C13: DMH-13 Peak Elev=18.79' = af Primary= af Secondary=.. af = af Pond C2: DMH-2 Peak Elev=19.7' = af Primary= af Secondary=.. af = af Pond C3: DMH-3 Peak Elev=189.1' = af Primary= af Secondary=.. af = af Pond C4: DMH4 Peak Elev=188.36' = af Primary= af Secondary=.. af = af Pond C: DMH- Peak Elev=187.66' = af Primary= af Secondary=.. af = af Pond C6: DMH-6 Peak Elev=186.92' = af Primary= af Secondary=.. af = af Pond C6a: CB Peak Elev=18.8' = af Primary= af Secondary=.. af = af Pond C7: DMH-7 Peak Elev=18.37' = af Primary= af Secondary=.. af = af Pond C8: DMH-8 Peak Elev=184.62' = af Primary= af Secondary=.. af = af Pond C9: DMH-9 Peak Elev=183.98' = af Primary= af Secondary=.. af = af Pond DRP: RDP Peak Elev=271.47' Storage=1,392 cf = af Discarded= af Primary= af Secondary=.. af = af Pond DS1: Lorraine Detention Peak Elev=278.72' Storage=12,941 cf = af Discarded= af Primary= af Secondary=.. af = af Pond DS2: Middle School Culvert Peak Elev=233.42' Storage=.176 af =1.6.8 af 36." Round Culvert n=.13 L=.' S=.22 '/' = af Pond DS3: Nyanza South Peak Elev=199.42' Storage=64 cf = af Discarded=..39 af Primary= af Secondary=1..11 af = af Pond DS4: East Wetlands Peak Elev=192.93' Storage=1.974 af = af Primary= af Secondary=.. af = af Pond DS: Settle Ponds Peak Elev=21.8' Storage=.73 af =.4.73 af =.. af Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 2 Year St Rainfall=3.36" Printed 6/17/216 Page 88 Pond DS6: Trolley Brook Peak Elev=191.33' Storage=6,894 cf = af Primary= af Secondary=.. af = af Pond DW1: Nyanza-W Ret/Det Peak Elev=2.66' Storage=36,79 cf = af Primary=.. af Secondary=.. af =.. af Pond DW2: MBTA Culverts Peak Elev=2.1' = af = af Pond DW3: MBTA Detention Peak Elev=198.69' Storage=.612 af = af = af Pond DW4: No. Wetlands Peak Elev=197.6' Storage=4.29 af = af = af Pond ND1: NW MBTA Wetlands Peak Elev=194.3' Storage=9,273 cf = af Discarded= af Primary=.. af = af Pond ND2: 24" RCP Pipe Peak Elev=191.24' = af 24." Round Culvert n=.13 L=33.' S=.3 '/' = af Total Runoff Area = ac Runoff Volume = af Average Runoff Depth =.6" 77.% Pervious = ac 22.9% Impervious = ac

153 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr Year St Rainfall=4.4" Printed 6/17/216 Page 89 Time span=.-72. hrs, dt=.1 hrs, 721 points x 3 Runoff by SCS TR-2 method, UH=SCS, Weighted-CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment N1: NW MBTA Runoff Area=8.3 ac 37.98% Impervious Runoff Depth=.8" Flow Length=7' Tc=19. min CN=8 Runoff= af Subcatchment N2: Metcalf Ave Runoff Area=2.2 ac 4.91% Impervious Runoff Depth=1.67" Tc=1. min CN=71 Runoff= af Subcatchment N3: Foster Ave Runoff Area=2.9 ac 9.3% Impervious Runoff Depth=1.9" Tc=1. min CN=74 Runoff=..48 af Subcatchment N4: 6 Pleasant Runoff Area=3. ac 62.4% Impervious Runoff Depth=2." Tc=1. min CN=76 Runoff= af Subcatchment N: Tilton Ave Runoff Area=3.8 ac 3.% Impervious Runoff Depth=.8" Tc=1. min CN=7 Runoff= af Subcatchment N6: Police/Fire Runoff Area=2.8 ac 8.% Impervious Runoff Depth=3.2" Tc=1. min CN=89 Runoff= af Subcatchment N7: Downtown Runoff Area=3.4 ac 8.% Impervious Runoff Depth=3.2" Tc=1. min CN=89 Runoff= af Subcatchment N8: Library Runoff Area=.8 ac 8.% Impervious Runoff Depth=3.2" Tc=1. min CN=89 Runoff= af Subcatchment S1: Lorraine Dr Runoff Area=22.3 ac 2.72% Impervious Runoff Depth=1.7" Flow Length=2,' Tc=16.3 min CN=72 Runoff= af Subcatchment S2: Middle School Runoff Area=63. ac 1.24% Impervious Runoff Depth=.46" Flow Length=2,3' Tc=4.2 min CN= Runoff= af Subcatchment S3: MBTA RD. CB-3 Runoff Area=6.6 ac.% Impervious Runoff Depth=.7" Flow Length=1,98' Tc=38.8 min CN= Runoff= af Subcatchment S4: South Wetlands Runoff Area=22.4 ac 4.46% Impervious Runoff Depth=.1" Flow Length=1,8' Tc=41.2 min CN=33 Runoff=.3.1 af Subcatchment S: SE Wetlands Runoff Area=17. ac 2.94% Impervious Runoff Depth=.7" Flow Length=9' Tc=37.7 min CN=38 Runoff=.16.1 af Subcatchment S6: Nyanza south Runoff Area=17. ac.% Impervious Runoff Depth=1.2" Flow Length=1,3' Tc=36.4 min CN=61 Runoff= af Subcatchment S7: East Wetlands Runoff Area=28.1 ac 36.44% Impervious Runoff Depth=.8" Flow Length=8' Tc=32.7 min CN=7 Runoff= af Subcatchment S8: Nyanza east Runoff Area=13. ac 29.3% Impervious Runoff Depth=2." Flow Length=9' Tc=1.3 min CN=76 Runoff= af Subcatchment S9: Settle Ponds Runoff Area=2.2 ac 9.9% Impervious Runoff Depth=.8" Flow Length=1' Tc=13.8 min CN=8 Runoff= af Trolley Brook Culvert - PROPOSED Condition Type III 24-hr Year St Rainfall=4.4" Printed 6/17/216 Page 9 Subcatchment W1: MBTA CB-2-Direct Runoff Area=2. ac.% Impervious Runoff Depth=." Flow Length=1,31' Tc=19.4 min CN=37 Runoff=.2.11 af Subcatchment W2: RDAP Development Runoff Area=3.7 ac 42.2% Impervious Runoff Depth=2.46" Tc=2.7 min CN=81 Runoff= af Subcatchment W3: MBTA CB-1 Runoff Area=.8 ac.% Impervious Runoff Depth=.34" Flow Length=' Tc=1.4 min CN=47 Runoff= af Subcatchment W4: MBTA Park Runoff Area=4. ac 1.% Impervious Runoff Depth=4.16" Tc=1. min CN=98 Runoff= af Subcatchment W: Nyanza West Runoff Area=13.7 ac 7.3% Impervious Runoff Depth=1.33" Flow Length=9' Slope=.1 '/' Tc=26.3 min CN=66 Runoff= af Subcatchment W6: No. Wetlands Runoff Area=32. ac 3.44% Impervious Runoff Depth=.91" Flow Length=1,' Tc=2.1 min CN=9 Runoff= af Subcatchment W7: Chemical Brook Runoff Area=9.9 ac 66.91% Impervious Runoff Depth=2.21" Flow Length=1,8' Tc=26.9 min CN=78 Runoff= af Subcatchment W8: Megunko Road Runoff Area=3.3 ac 72.% Impervious Runoff Depth=2.46" Flow Length=9' Slope=. '/' Tc=17.3 min CN=81 Runoff= af Reach CB1: Chemical Brook Avg. Flow Depth=.96' Max Vel=2.38 fps = af n=.22 L=1,.' S=.23 '/' Capacity=64.47 = af Reach FL: Flooding = af = af Reach RC1: To Sudbury River = af = af Reach RN1: Swale Avg. Flow Depth=.23' Max Vel=1.64 fps = af n=.22 L=42.' S=.48 '/' Capacity= = af Reach RW1: Thru North Wetlands Avg. Flow Depth=.9' Max Vel=.3 fps = af n=.4 L=1,.' S=.2 '/' Capacity=27.3 =.9.12 af Reach SR1: To East Wetlands Avg. Flow Depth=.' Max Vel=3.9 fps = af n=.3 L=1,.' S=.33 '/' Capacity= = af Reach TB1: Trolley Brook Avg. Flow Depth=.62' Max Vel=2.49 fps = af n=.3 L=18.' S=.6 '/' Capacity=1, = af Pond C: Inlet to Culvert Peak Elev=191.88' = af Primary= af Secondary= af = af Pond C1: DMH - 1 Peak Elev=191.94' = af Primary= af Secondary=.2. af = af Pond C1: DMH-1 Peak Elev=186.3' = af Primary= af Secondary=.. af = af

154 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr Year St Rainfall=4.4" Printed 6/17/216 Page 91 Pond C11: DMH-11 Peak Elev=18.36' = af Primary= af Secondary=.. af = af Pond C12: DMH-12 Peak Elev=184.3' = af Primary= af Secondary=.. af = af Pond C13: DMH-13 Peak Elev=181.63' = af Primary= af Secondary=.. af = af Pond C2: DMH-2 Peak Elev=191.3' = af Primary= af Secondary=2.. af = af Pond C3: DMH-3 Peak Elev=189.97' = af Primary= af Secondary=.. af = af Pond C4: DMH4 Peak Elev=189.18' = af Primary= af Secondary=.. af = af Pond C: DMH- Peak Elev=188.82' = af Primary= af Secondary=.. af = af Pond C6: DMH-6 Peak Elev=188.7' = af Primary= af Secondary=.. af = af Pond C6a: CB Peak Elev=188.2' = af Primary= af Secondary=.. af = af Pond C7: DMH-7 Peak Elev=187.86' = af Primary= af Secondary=.. af = af Pond C8: DMH-8 Peak Elev=187.68' = af Primary= af Secondary=.. af = af Pond C9: DMH-9 Peak Elev=186.83' = af Primary= af Secondary=.. af = af Pond DRP: RDP Peak Elev=272.34' Storage=8,472 cf = af Discarded= af Primary= af Secondary=.. af = af Pond DS1: Lorraine Detention Peak Elev=28.3' Storage=22,947 cf = af Discarded= af Primary= af Secondary=.. af = af Pond DS2: Middle School Culvert Peak Elev=233.9' Storage=.33 af = af 36." Round Culvert n=.13 L=.' S=.22 '/' = af Pond DS3: Nyanza South Peak Elev=199.82' Storage=999 cf = af Discarded=.6.44 af Primary= af Secondary= af = af Pond DS4: East Wetlands Peak Elev=193.18' Storage=12.66 af = af Primary= af Secondary=.. af = af Pond DS: Settle Ponds Peak Elev=216.21' Storage=.17 af = af =.. af Trolley Brook Culvert - PROPOSED Condition Type III 24-hr Year St Rainfall=4.4" Printed 6/17/216 Page 92 Pond DS6: Trolley Brook Peak Elev=191.92' Storage=12,227 cf = af Primary= af Secondary=.. af = af Pond DW1: Nyanza-W Ret/Det Peak Elev=21.32' Storage=8,2 cf = af Primary= af Secondary=.. af = af Pond DW2: MBTA Culverts Peak Elev=2.3' = af = af Pond DW3: MBTA Detention Peak Elev=199.2' Storage=.788 af = af = af Pond DW4: No. Wetlands Peak Elev=197.91' Storage=.34 af = af = af Pond ND1: NW MBTA Wetlands Peak Elev=194.7' Storage=19,842 cf = af Discarded= af Primary=.. af = af Pond ND2: 24" RCP Pipe Peak Elev=192.41' = af 24." Round Culvert n=.13 L=33.' S=.3 '/' = af Total Runoff Area = ac Runoff Volume = af Average Runoff Depth = 1.14" 77.% Pervious = ac 22.9% Impervious = ac

155 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 2 Year St Rainfall=6.43" Printed 6/17/216 Page 93 Time span=.-72. hrs, dt=.1 hrs, 721 points x 3 Runoff by SCS TR-2 method, UH=SCS, Weighted-CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment N1: NW MBTA Runoff Area=8.3 ac 37.98% Impervious Runoff Depth=2.3" Flow Length=7' Tc=19. min CN=8 Runoff= af Subcatchment N2: Metcalf Ave Runoff Area=2.2 ac 4.91% Impervious Runoff Depth=3.2" Tc=1. min CN=71 Runoff= af Subcatchment N3: Foster Ave Runoff Area=2.9 ac 9.3% Impervious Runoff Depth=3." Tc=1. min CN=74 Runoff=1..88 af Subcatchment N4: 6 Pleasant Runoff Area=3. ac 62.4% Impervious Runoff Depth=3.7" Tc=1. min CN=76 Runoff= af Subcatchment N: Tilton Ave Runoff Area=3.8 ac 3.% Impervious Runoff Depth=1.94" Tc=1. min CN=7 Runoff= af Subcatchment N6: Police/Fire Runoff Area=2.8 ac 8.% Impervious Runoff Depth=.1" Tc=1. min CN=89 Runoff= af Subcatchment N7: Downtown Runoff Area=3.4 ac 8.% Impervious Runoff Depth=.1" Tc=1. min CN=89 Runoff= af Subcatchment N8: Library Runoff Area=.8 ac 8.% Impervious Runoff Depth=.1" Tc=1. min CN=89 Runoff= af Subcatchment S1: Lorraine Dr Runoff Area=22.3 ac 2.72% Impervious Runoff Depth=3.3" Flow Length=2,' Tc=16.3 min CN=72 Runoff= af Subcatchment S2: Middle School Runoff Area=63. ac 1.24% Impervious Runoff Depth=1.36" Flow Length=2,3' Tc=4.2 min CN= Runoff= af Subcatchment S3: MBTA RD. CB-3 Runoff Area=6.6 ac.% Impervious Runoff Depth=1.77" Flow Length=1,98' Tc=38.8 min CN= Runoff= af Subcatchment S4: South Wetlands Runoff Area=22.4 ac 4.46% Impervious Runoff Depth=.2" Flow Length=1,8' Tc=41.2 min CN=33 Runoff= af Subcatchment S: SE Wetlands Runoff Area=17. ac 2.94% Impervious Runoff Depth=.1" Flow Length=9' Tc=37.7 min CN=38 Runoff= af Subcatchment S6: Nyanza south Runoff Area=17. ac.% Impervious Runoff Depth=2.3" Flow Length=1,3' Tc=36.4 min CN=61 Runoff= af Subcatchment S7: East Wetlands Runoff Area=28.1 ac 36.44% Impervious Runoff Depth=1.94" Flow Length=8' Tc=32.7 min CN=7 Runoff= af Subcatchment S8: Nyanza east Runoff Area=13. ac 29.3% Impervious Runoff Depth=3.7" Flow Length=9' Tc=1.3 min CN=76 Runoff= af Subcatchment S9: Settle Ponds Runoff Area=2.2 ac 9.9% Impervious Runoff Depth=2.3" Flow Length=1' Tc=13.8 min CN=8 Runoff= af Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 2 Year St Rainfall=6.43" Printed 6/17/216 Page 94 Subcatchment W1: MBTA CB-2-Direct Runoff Area=2. ac.% Impervious Runoff Depth=.46" Flow Length=1,31' Tc=19.4 min CN=37 Runoff=.37.9 af Subcatchment W2: RDAP Development Runoff Area=3.7 ac 42.2% Impervious Runoff Depth=4.28" Tc=2.7 min CN=81 Runoff= af Subcatchment W3: MBTA CB-1 Runoff Area=.8 ac.% Impervious Runoff Depth=1.13" Flow Length=' Tc=1.4 min CN=47 Runoff= af Subcatchment W4: MBTA Park Runoff Area=4. ac 1.% Impervious Runoff Depth=6.19" Tc=1. min CN=98 Runoff= af Subcatchment W: Nyanza West Runoff Area=13.7 ac 7.3% Impervious Runoff Depth=2.76" Flow Length=9' Slope=.1 '/' Tc=26.3 min CN=66 Runoff= af Subcatchment W6: No. Wetlands Runoff Area=32. ac 3.44% Impervious Runoff Depth=2.12" Flow Length=1,' Tc=2.1 min CN=9 Runoff= af Subcatchment W7: Chemical Brook Runoff Area=9.9 ac 66.91% Impervious Runoff Depth=3.96" Flow Length=1,8' Tc=26.9 min CN=78 Runoff= af Subcatchment W8: Megunko Road Runoff Area=3.3 ac 72.% Impervious Runoff Depth=4.28" Flow Length=9' Slope=. '/' Tc=17.3 min CN=81 Runoff= af Reach CB1: Chemical Brook Avg. Flow Depth=1.4' Max Vel=2.93 fps = af n=.22 L=1,.' S=.23 '/' Capacity=64.47 = af Reach FL: Flooding = af = af Reach RC1: To Sudbury River = af = af Reach RN1: Swale Avg. Flow Depth=.3' Max Vel=2.1 fps = af n=.22 L=42.' S=.48 '/' Capacity= = af Reach RW1: Thru North Wetlands Avg. Flow Depth=.23' Max Vel=.6 fps = af n=.4 L=1,.' S=.2 '/' Capacity=27.3 =.4.29 af Reach SR1: To East Wetlands Avg. Flow Depth=.72' Max Vel=4.92 fps = af n=.3 L=1,.' S=.33 '/' Capacity= = af Reach TB1: Trolley Brook Avg. Flow Depth=.77' Max Vel=2.82 fps = af n=.3 L=18.' S=.6 '/' Capacity=1, = af Pond C: Inlet to Culvert Peak Elev=192.14' = af Primary= af Secondary= af = af Pond C1: DMH - 1 Peak Elev=192.1' = af Primary= af Secondary= af = af Pond C1: DMH-1 Peak Elev=188.46' = af Primary= af Secondary= af = af

156 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 2 Year St Rainfall=6.43" Printed 6/17/216 Page 9 Pond C11: DMH-11 Peak Elev=187.' = af Primary= af Secondary= af = af Pond C12: DMH-12 Peak Elev=18.7' = af Primary= af Secondary=2.2.2 af = af Pond C13: DMH-13 Peak Elev=182.2' = af Primary= af Secondary=.. af = af Pond C2: DMH-2 Peak Elev=191.74' = af Primary= af Secondary= af = af Pond C3: DMH-3 Peak Elev=191.31' = af Primary= af Secondary= af = af Pond C4: DMH4 Peak Elev=19.96' = af Primary= af Secondary=.. af = af Pond C: DMH- Peak Elev=191.2' = af Primary= af Secondary=.. af = af Pond C6: DMH-6 Peak Elev=19.71' = af Primary= af Secondary=.97.1 af = af Pond C6a: CB Peak Elev=19.28' = af Primary= af Secondary= af = af Pond C7: DMH-7 Peak Elev=19.62' = af Primary= af Secondary=.. af = af Pond C8: DMH-8 Peak Elev=189.96' = af Primary= af Secondary=.. af = af Pond C9: DMH-9 Peak Elev=189.1' = af Primary= af Secondary= af = af Pond DRP: RDP Peak Elev=273.7' Storage=132,239 cf = af Discarded= af Primary= af Secondary=.. af = af Pond DS1: Lorraine Detention Peak Elev=282.4' Storage=4,33 cf = af Discarded=.6.28 af Primary= af Secondary= af = af Pond DS2: Middle School Culvert Peak Elev=23.17' Storage=1.431 af = af 36." Round Culvert n=.13 L=.' S=.22 '/' = af Pond DS3: Nyanza South Peak Elev=2.63' Storage=2,317 cf = af Discarded=.13.6 af Primary= af Secondary= af = af Pond DS4: East Wetlands Peak Elev=193.96' Storage= af = af Primary= af Secondary=.. af = af Pond DS: Settle Ponds Peak Elev=217.4' Storage=.372 af = af =.. af Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 2 Year St Rainfall=6.43" Printed 6/17/216 Page 96 Pond DS6: Trolley Brook Peak Elev=193.16' Storage=4,37 cf = af Primary= af Secondary=.. af = af Pond DW1: Nyanza-W Ret/Det Peak Elev=22.6' Storage=11,944 cf = af Primary= af Secondary=.. af = af Pond DW2: MBTA Culverts Peak Elev=2.8' = af = af Pond DW3: MBTA Detention Peak Elev=199.63' Storage=1.114 af = af = af Pond DW4: No. Wetlands Peak Elev=198.39' Storage=8.13 af = af = af Pond ND1: NW MBTA Wetlands Peak Elev=194.96' Storage=28,32 cf = af Discarded=.21.7 af Primary= af = af Pond ND2: 24" RCP Pipe Peak Elev=194.6' = af 24." Round Culvert n=.13 L=33.' S=.3 '/' = af Total Runoff Area = ac Runoff Volume = 62.2 af Average Runoff Depth = 2.33" 77.% Pervious = ac 22.9% Impervious = ac

157 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr Year St Rainfall=7.34" Printed 6/17/216 Page 97 Time span=.-72. hrs, dt=.1 hrs, 721 points x 3 Runoff by SCS TR-2 method, UH=SCS, Weighted-CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment N1: NW MBTA Runoff Area=8.3 ac 37.98% Impervious Runoff Depth=2.64" Flow Length=7' Tc=19. min CN=8 Runoff= af Subcatchment N2: Metcalf Ave Runoff Area=2.2 ac 4.91% Impervious Runoff Depth=4.1" Tc=1. min CN=71 Runoff= af Subcatchment N3: Foster Ave Runoff Area=2.9 ac 9.3% Impervious Runoff Depth=4.34" Tc=1. min CN=74 Runoff= af Subcatchment N4: 6 Pleasant Runoff Area=3. ac 62.4% Impervious Runoff Depth=4.6" Tc=1. min CN=76 Runoff= af Subcatchment N: Tilton Ave Runoff Area=3.8 ac 3.% Impervious Runoff Depth=2.4" Tc=1. min CN=7 Runoff=9.4.8 af Subcatchment N6: Police/Fire Runoff Area=2.8 ac 8.% Impervious Runoff Depth=6.4" Tc=1. min CN=89 Runoff= af Subcatchment N7: Downtown Runoff Area=3.4 ac 8.% Impervious Runoff Depth=6.4" Tc=1. min CN=89 Runoff= af Subcatchment N8: Library Runoff Area=.8 ac 8.% Impervious Runoff Depth=6.4" Tc=1. min CN=89 Runoff= af Subcatchment S1: Lorraine Dr Runoff Area=22.3 ac 2.72% Impervious Runoff Depth=4.12" Flow Length=2,' Tc=16.3 min CN=72 Runoff= af Subcatchment S2: Middle School Runoff Area=63. ac 1.24% Impervious Runoff Depth=1.86" Flow Length=2,3' Tc=4.2 min CN= Runoff= af Subcatchment S3: MBTA RD. CB-3 Runoff Area=6.6 ac.% Impervious Runoff Depth=2.34" Flow Length=1,98' Tc=38.8 min CN= Runoff= af Subcatchment S4: South Wetlands Runoff Area=22.4 ac 4.46% Impervious Runoff Depth=.46" Flow Length=1,8' Tc=41.2 min CN=33 Runoff= af Subcatchment S: SE Wetlands Runoff Area=17. ac 2.94% Impervious Runoff Depth=.82" Flow Length=9' Tc=37.7 min CN=38 Runoff= af Subcatchment S6: Nyanza south Runoff Area=17. ac.% Impervious Runoff Depth=2.9" Flow Length=1,3' Tc=36.4 min CN=61 Runoff= af Subcatchment S7: East Wetlands Runoff Area=28.1 ac 36.44% Impervious Runoff Depth=2.4" Flow Length=8' Tc=32.7 min CN=7 Runoff= af Subcatchment S8: Nyanza east Runoff Area=13. ac 29.3% Impervious Runoff Depth=4.6" Flow Length=9' Tc=1.3 min CN=76 Runoff= af Subcatchment S9: Settle Ponds Runoff Area=2.2 ac 9.9% Impervious Runoff Depth=2.64" Flow Length=1' Tc=13.8 min CN=8 Runoff= af Trolley Brook Culvert - PROPOSED Condition Type III 24-hr Year St Rainfall=7.34" Printed 6/17/216 Page 98 Subcatchment W1: MBTA CB-2-Direct Runoff Area=2. ac.% Impervious Runoff Depth=.74" Flow Length=1,31' Tc=19.4 min CN=37 Runoff= af Subcatchment W2: RDAP Development Runoff Area=3.7 ac 42.2% Impervious Runoff Depth=.12" Tc=2.7 min CN=81 Runoff= af Subcatchment W3: MBTA CB-1 Runoff Area=.8 ac.% Impervious Runoff Depth=1.8" Flow Length=' Tc=1.4 min CN=47 Runoff= af Subcatchment W4: MBTA Park Runoff Area=4. ac 1.% Impervious Runoff Depth=7.1" Tc=1. min CN=98 Runoff= af Subcatchment W: Nyanza West Runoff Area=13.7 ac 7.3% Impervious Runoff Depth=3.47" Flow Length=9' Slope=.1 '/' Tc=26.3 min CN=66 Runoff= af Subcatchment W6: No. Wetlands Runoff Area=32. ac 3.44% Impervious Runoff Depth=2.74" Flow Length=1,' Tc=2.1 min CN=9 Runoff= af Subcatchment W7: Chemical Brook Runoff Area=9.9 ac 66.91% Impervious Runoff Depth=4.78" Flow Length=1,8' Tc=26.9 min CN=78 Runoff= af Subcatchment W8: Megunko Road Runoff Area=3.3 ac 72.% Impervious Runoff Depth=.12" Flow Length=9' Slope=. '/' Tc=17.3 min CN=81 Runoff= af Reach CB1: Chemical Brook Avg. Flow Depth=1.64' Max Vel=3.2 fps = af n=.22 L=1,.' S=.23 '/' Capacity=64.47 = af Reach FL: Flooding = af = af Reach RC1: To Sudbury River = af = af Reach RN1: Swale Avg. Flow Depth=.4' Max Vel=2.26 fps = af n=.22 L=42.' S=.48 '/' Capacity= = af Reach RW1: Thru North Wetlands Avg. Flow Depth=.3' Max Vel=.7 fps = af n=.4 L=1,.' S=.2 '/' Capacity=27.3 = af Reach SR1: To East Wetlands Avg. Flow Depth=.79' Max Vel=.2 fps = af n=.3 L=1,.' S=.33 '/' Capacity= = af Reach TB1: Trolley Brook Avg. Flow Depth=.82' Max Vel=2.93 fps = af n=.3 L=18.' S=.6 '/' Capacity=1, = af Pond C: Inlet to Culvert Peak Elev=192.24' = af Primary= af Secondary= af = af Pond C1: DMH - 1 Peak Elev=192.1' = af Primary= af Secondary=7..7 af = af Pond C1: DMH-1 Peak Elev=188.74' = af Primary= af Secondary= af = af

158 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr Year St Rainfall=7.34" Printed 6/17/216 Page 99 Pond C11: DMH-11 Peak Elev=187.61' = af Primary= af Secondary= af = af Pond C12: DMH-12 Peak Elev=18.1' = af Primary= af Secondary= af = af Pond C13: DMH-13 Peak Elev=182.4' = af Primary= af Secondary=.. af = af Pond C2: DMH-2 Peak Elev=191.79' = af Primary= af Secondary= af = af Pond C3: DMH-3 Peak Elev=191.2' = af Primary= af Secondary= af = af Pond C4: DMH4 Peak Elev=191.11' = af Primary= af Secondary=.. af = af Pond C: DMH- Peak Elev=191.28' = af Primary= af Secondary=.. af = af Pond C6: DMH-6 Peak Elev=19.8' = af Primary= af Secondary=1..1 af = af Pond C6a: CB Peak Elev=19.29' = af Primary= af Secondary= af = af Pond C7: DMH-7 Peak Elev=19.69' = af Primary= af Secondary=.. af = af Pond C8: DMH-8 Peak Elev=19.2' = af Primary= af Secondary=.. af = af Pond C9: DMH-9 Peak Elev=189.1' = af Primary= af Secondary= af = af Pond DRP: RDP Peak Elev=274.36' Storage=16,262 cf = af Discarded= af Primary= af Secondary=.. af = af Pond DS1: Lorraine Detention Peak Elev=282.83' Storage=44,28 cf = af Discarded= af Primary= af Secondary= af = af Pond DS2: Middle School Culvert Peak Elev=23.73' Storage=2.37 af = af 36." Round Culvert n=.13 L=.' S=.22 '/' = af Pond DS3: Nyanza South Peak Elev=21.4' Storage=3,48 cf = af Discarded= af Primary= af Secondary= af = af Pond DS4: East Wetlands Peak Elev=194.6' Storage=21.99 af = af Primary= af Secondary=.. af = af Pond DS: Settle Ponds Peak Elev=217.42' Storage=.48 af = af =.. af Trolley Brook Culvert - PROPOSED Condition Type III 24-hr Year St Rainfall=7.34" Printed 6/17/216 Page 1 Pond DS6: Trolley Brook Peak Elev=193.78' Storage=67,764 cf = af Primary= af Secondary=.. af = af Pond DW1: Nyanza-W Ret/Det Peak Elev=23.23' Storage=14,748 cf = af Primary= af Secondary=.. af = af Pond DW2: MBTA Culverts Peak Elev=2.99' = af = af Pond DW3: MBTA Detention Peak Elev=199.88' Storage=1.2 af = af = af Pond DW4: No. Wetlands Peak Elev=198.62' Storage=9.38 af = af = af Pond ND1: NW MBTA Wetlands Peak Elev=19.12' Storage=33,847 cf = af Discarded= af Primary= af = af Pond ND2: 24" RCP Pipe Peak Elev=196.1' = af 24." Round Culvert n=.13 L=33.' S=.3 '/' = af Total Runoff Area = ac Runoff Volume = af Average Runoff Depth = 2.94" 77.% Pervious = ac 22.9% Impervious = ac

159 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=8.2" Printed 6/17/216 Page 11 Time span=.-72. hrs, dt=.1 hrs, 721 points x 3 Runoff by SCS TR-2 method, UH=SCS, Weighted-CN Reach routing by Dyn-Stor-Ind method - Pond routing by Dyn-Stor-Ind method Subcatchment N1: NW MBTA Runoff Area=8.3 ac 37.98% Impervious Runoff Depth=3.29" Flow Length=7' Tc=19. min CN=8 Runoff= af Subcatchment N2: Metcalf Ave Runoff Area=2.2 ac 4.91% Impervious Runoff Depth=4.8" Tc=1. min CN=71 Runoff= af Subcatchment N3: Foster Ave Runoff Area=2.9 ac 9.3% Impervious Runoff Depth=.1" Tc=1. min CN=74 Runoff= af Subcatchment N4: 6 Pleasant Runoff Area=3. ac 62.4% Impervious Runoff Depth=.39" Tc=1. min CN=76 Runoff= af Subcatchment N: Tilton Ave Runoff Area=3.8 ac 3.% Impervious Runoff Depth=3.18" Tc=1. min CN=7 Runoff= af Subcatchment N6: Police/Fire Runoff Area=2.8 ac 8.% Impervious Runoff Depth=6.93" Tc=1. min CN=89 Runoff= af Subcatchment N7: Downtown Runoff Area=3.4 ac 8.% Impervious Runoff Depth=6.93" Tc=1. min CN=89 Runoff= af Subcatchment N8: Library Runoff Area=.8 ac 8.% Impervious Runoff Depth=6.93" Tc=1. min CN=89 Runoff= af Subcatchment S1: Lorraine Dr Runoff Area=22.3 ac 2.72% Impervious Runoff Depth=4.91" Flow Length=2,' Tc=16.3 min CN=72 Runoff= af Subcatchment S2: Middle School Runoff Area=63. ac 1.24% Impervious Runoff Depth=2.4" Flow Length=2,3' Tc=4.2 min CN= Runoff= af Subcatchment S3: MBTA RD. CB-3 Runoff Area=6.6 ac.% Impervious Runoff Depth=2.96" Flow Length=1,98' Tc=38.8 min CN= Runoff= af Subcatchment S4: South Wetlands Runoff Area=22.4 ac 4.46% Impervious Runoff Depth=.72" Flow Length=1,8' Tc=41.2 min CN=33 Runoff= af Subcatchment S: SE Wetlands Runoff Area=17. ac 2.94% Impervious Runoff Depth=1.17" Flow Length=9' Tc=37.7 min CN=38 Runoff= af Subcatchment S6: Nyanza south Runoff Area=17. ac.% Impervious Runoff Depth=3.64" Flow Length=1,3' Tc=36.4 min CN=61 Runoff= af Subcatchment S7: East Wetlands Runoff Area=28.1 ac 36.44% Impervious Runoff Depth=3.18" Flow Length=8' Tc=32.7 min CN=7 Runoff= af Subcatchment S8: Nyanza east Runoff Area=13. ac 29.3% Impervious Runoff Depth=.39" Flow Length=9' Tc=1.3 min CN=76 Runoff= af Subcatchment S9: Settle Ponds Runoff Area=2.2 ac 9.9% Impervious Runoff Depth=3.29" Flow Length=1' Tc=13.8 min CN=8 Runoff= af Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=8.2" Printed 6/17/216 Page 12 Subcatchment W1: MBTA CB-2-Direct Runoff Area=2. ac.% Impervious Runoff Depth=1.7" Flow Length=1,31' Tc=19.4 min CN=37 Runoff= af Subcatchment W2: RDAP Development Runoff Area=3.7 ac 42.2% Impervious Runoff Depth=.98" Tc=2.7 min CN=81 Runoff= af Subcatchment W3: MBTA CB-1 Runoff Area=.8 ac.% Impervious Runoff Depth=2.8" Flow Length=' Tc=1.4 min CN=47 Runoff= af Subcatchment W4: MBTA Park Runoff Area=4. ac 1.% Impervious Runoff Depth=8.1" Tc=1. min CN=98 Runoff= af Subcatchment W: Nyanza West Runoff Area=13.7 ac 7.3% Impervious Runoff Depth=4.21" Flow Length=9' Slope=.1 '/' Tc=26.3 min CN=66 Runoff= af Subcatchment W6: No. Wetlands Runoff Area=32. ac 3.44% Impervious Runoff Depth=3.41" Flow Length=1,' Tc=2.1 min CN=9 Runoff= af Subcatchment W7: Chemical Brook Runoff Area=9.9 ac 66.91% Impervious Runoff Depth=.62" Flow Length=1,8' Tc=26.9 min CN=78 Runoff= af Subcatchment W8: Megunko Road Runoff Area=3.3 ac 72.% Impervious Runoff Depth=.98" Flow Length=9' Slope=. '/' Tc=17.3 min CN=81 Runoff= af Reach CB1: Chemical Brook Avg. Flow Depth=1.86' Max Vel=3.44 fps = af n=.22 L=1,.' S=.23 '/' Capacity=64.47 = af Reach FL: Flooding = af = af Reach RC1: To Sudbury River = af = af Reach RN1: Swale Avg. Flow Depth=.44' Max Vel=2.4 fps = af n=.22 L=42.' S=.48 '/' Capacity= = af Reach RW1: Thru North Wetlands Avg. Flow Depth=.37' Max Vel=.8 fps = af n=.4 L=1,.' S=.2 '/' Capacity=27.3 = af Reach SR1: To East Wetlands Avg. Flow Depth=.83' Max Vel=.37 fps = af n=.3 L=1,.' S=.33 '/' Capacity= = af Reach TB1: Trolley Brook Avg. Flow Depth=.86' Max Vel=3.1 fps = af n=.3 L=18.' S=.6 '/' Capacity=1, = af Pond C: Inlet to Culvert Peak Elev=192.27' = af Primary= af Secondary= af = af Pond C1: DMH - 1 Peak Elev=193.12' = af Primary= af Secondary= af = af Pond C1: DMH-1 Peak Elev=188.' = af Primary= af Secondary= af = af

160 Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=8.2" Printed 6/17/216 Page 13 Pond C11: DMH-11 Peak Elev=188.1' = af Primary= af Secondary=12.3. af = af Pond C12: DMH-12 Peak Elev=18.9' = af Primary= af Secondary=.4.38 af = af Pond C13: DMH-13 Peak Elev=182.9' = af Primary= af Secondary=.. af = af Pond C2: DMH-2 Peak Elev=192.37' = af Primary= af Secondary= af = af Pond C3: DMH-3 Peak Elev=191.6' = af Primary= af Secondary= af = af Pond C4: DMH4 Peak Elev=191.71' = af Primary= af Secondary=.3. af = af Pond C: DMH- Peak Elev=191.3' = af Primary= af Secondary=.. af = af Pond C6: DMH-6 Peak Elev=19.77' = af Primary= af Secondary= af = af Pond C6a: CB Peak Elev=19.8' = af Primary= af Secondary= af = af Pond C7: DMH-7 Peak Elev=19.94' = af Primary= af Secondary=.. af = af Pond C8: DMH-8 Peak Elev=19.18' = af Primary= af Secondary=.. af = af Pond C9: DMH-9 Peak Elev=189.' = af Primary= af Secondary=8.77. af = af Pond DRP: RDP Peak Elev=27.' Storage=19,31 cf = af Discarded= af Primary= af Secondary=.. af = af Pond DS1: Lorraine Detention Peak Elev=283.1' Storage=48,19 cf = af Discarded= af Primary= af Secondary= af = af Pond DS2: Middle School Culvert Peak Elev=236.32' Storage=3.642 af = af 36." Round Culvert n=.13 L=.' S=.22 '/' = af Pond DS3: Nyanza South Peak Elev=21.76' Storage=6,82 cf = af Discarded= af Primary= af Secondary= af = af Pond DS4: East Wetlands Peak Elev=19.27' Storage= af = af Primary= af Secondary=.. af = af Pond DS: Settle Ponds Peak Elev=217.8' Storage=.64 af = af =.. af Trolley Brook Culvert - PROPOSED Condition Type III 24-hr 1 Year St Rainfall=8.2" Printed 6/17/216 Page 14 Pond DS6: Trolley Brook Peak Elev=194.31' Storage=98,19 cf = af Primary= af Secondary=.. af = af Pond DW1: Nyanza-W Ret/Det Peak Elev=23.8' Storage=172,768 cf = af Primary= af Secondary=.. af = af Pond DW2: MBTA Culverts Peak Elev=21.11' = af = af Pond DW3: MBTA Detention Peak Elev=2.13' Storage=1.394 af = af = af Pond DW4: No. Wetlands Peak Elev=198.8' Storage=1.998 af = af = af Pond ND1: NW MBTA Wetlands Peak Elev=19.29' Storage=4,96 cf = af Discarded= af Primary= af = af Pond ND2: 24" RCP Pipe Peak Elev=197.9' = af 24." Round Culvert n=.13 L=33.' S=.3 '/' = af Total Runoff Area = ac Runoff Volume = af Average Runoff Depth = 3.9" 77.% Pervious = ac 22.9% Impervious = ac

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162 HYDROLOGIC/HYDRAULIC ANALYSIS REPORT FOR THE TROLLEY BROOK CULVERT ASHLAND, MA APPENDIX E NRCS Soils Data

163 Hydrologic Soil Group Middlesex County, Massachusetts (Trolley Brook Culvert Watershed) ' 2'' W ' 33'' W 42 1' 47'' N 42 1' 47'' N ' 6'' N ' 2'' W 71 27' 33'' W 42 14' 6'' N N Map Scale: 1:11,1 if printed on A landscape (11" x 8.") sheet. Meters Feet Map projection: Web Mercator Corner coordinates: WGS84 Edge tics: UTM Zone 19N WGS84 Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 6/14/216 Page 1 of 4

164 MAP LEGEND MAP INFORMATION Hydrologic Soil Group Middlesex County, Massachusetts (Trolley Brook Culvert Watershed) Area of Interest (AOI) Area of Interest (AOI) Soils Soil Rating Polygons A A/D B B/D C C/D D Not rated or not available Soil Rating Lines A A/D B B/D C C/D D Not rated or not available Soil Rating Points A A/D B B/D C C/D D Not rated or not available Water Features Streams and Canals Transportation Rails Interstate Highways US Routes Major Roads Local Roads Background Aerial Photography The soil surveys that comprise your AOI were mapped at 1:2,. Warning: Soil Map may not be valid at this scale. Enlargement of maps beyond the scale of mapping can cause misunderstanding of the detail of mapping and accuracy of soil line placement. The maps do not show the small areas of contrasting soils that could have been shown at a more detailed scale. Please rely on the bar scale on each map sheet for map measurements. Source of Map: Natural Resources Conservation Service Web Soil Survey URL: Coordinate System: Web Mercator (EPSG:387) Maps from the Web Soil Survey are based on the Web Mercator projection, which preserves direction and shape but distorts distance and area. A projection that preserves area, such as the Albers equal-area conic projection, should be used if more accurate calculations of distance or area are required. This product is generated from the USDA-NRCS certified data as of the version date(s) listed below. Soil Survey Area: Middlesex County, Massachusetts Survey Area Data: Version 1, Sep 28, 21 Soil map units are labeled (as space allows) for map scales 1:, or larger. Date(s) aerial images were photographed: Sep 12, 214 Sep 28, 214 The orthophoto or other base map on which the soil lines were compiled and digitized probably differs from the background imagery displayed on these maps. As a result, some minor shifting of map unit boundaries may be evident. Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 6/14/216 Page 2 of 4

165 Hydrologic Soil Group Middlesex County, Massachusetts Trolley Brook Culvert Watershed Hydrologic Soil Group 3A 73B 14C 16C 37B 37D 312B Hydrologic Soil Group Summary by Map Unit Middlesex County, Massachusetts (MA17) Map unit symbol Map unit name Rating Acres in AOI Percent of AOI Freetown muck, ponded, to 1 percent slopes Whitman fine sandy loam, to percent slopes, extremely stony Hollis-Rock outcrop- Charlton complex, 3 to 1 percent slopes Narragansett-Hollis- Rock outcrop complex, 3 to 1 percent slopes Paxton fine sandy loam, to 8 percent slopes, extremely stony Paxton fine sandy loam, 1 to 2 percent slopes, extremely stony Woodbridge fine sandy loam, to 8 percent slopes, extremely stony 41B Narragansett silt loam, 3 to 8 percent slopes 416B Narragansett silt loam, 3 to 8 percent slopes, very stony 416C Narragansett silt loam, 8 to 1 percent slopes, very stony 416D 626B Narragansett silt loam, 1 to 2 percent slopes, very stony Merrimac-Urban land complex, to 8 percent slopes B/D % D % A.7 1.6% A % C % C % C/D % A 2.4.7% A % A % A % A % 64 Udorthents, loamy % 6 Udorthents, wet substratum 66 Udorthents-Urban land complex 1.9.% % Totals for Area of Interest % Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 6/14/216 Page 3 of 4

166 Hydrologic Soil Group Middlesex County, Massachusetts Trolley Brook Culvert Watershed Description Hydrologic soil groups are based on estimates of runoff potential. Soils are assigned to one of four groups according to the rate of water infiltration when the soils are not protected by vegetation, are thoroughly wet, and receive precipitation from long-duration storms. The soils in the United States are assigned to four groups (A, B, C, and D) and three dual classes (A/D, B/D, and C/D). The groups are defined as follows: Group A. Soils having a high infiltration rate (low runoff potential) when thoroughly wet. These consist mainly of deep, well drained to excessively drained sands or gravelly sands. These soils have a high rate of water transmission. Group B. Soils having a moderate infiltration rate when thoroughly wet. These consist chiefly of moderately deep or deep, moderately well drained or well drained soils that have moderately fine texture to moderately coarse texture. These soils have a moderate rate of water transmission. Group C. Soils having a slow infiltration rate when thoroughly wet. These consist chiefly of soils having a layer that impedes the downward movement of water or soils of moderately fine texture or fine texture. These soils have a slow rate of water transmission. Group D. Soils having a very slow infiltration rate (high runoff potential) when thoroughly wet. These consist chiefly of clays that have a high shrink-swell potential, soils that have a high water table, soils that have a claypan or clay layer at or near the surface, and soils that are shallow over nearly impervious material. These soils have a very slow rate of water transmission. If a soil is assigned to a dual hydrologic group (A/D, B/D, or C/D), the first letter is for drained areas and the second is for undrained areas. Only the soils that in their natural condition are in group D are assigned to dual classes. Rating Options Aggregation Method: Dominant Condition Component Percent Cutoff: None Specified Tie-break Rule: Higher Natural Resources Conservation Service Web Soil Survey National Cooperative Soil Survey 6/14/216 Page 4 of 4

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168 HYDROLOGIC/HYDRAULIC ANALYSIS REPORT FOR THE TROLLEY BROOK CULVERT ASHLAND, MA APPENDIX F Rainfall data obtained from NOAA Atlas 14

169 Precipitation Frequency Data Server Page 1 of 4 6/8/216 NOAA Atlas 14, Volume 1, Version 2 ASHLAND Station ID: Location name: Ashland, Massachusetts, US* Latitude: 42.2, Longitude: Elevation: Elevation (station metadata): 23 ft* * source: Google Maps POINT PRECIPITATION FREQUENCY ESTIMATES Sanja Perica, Sandra Pavlovic, Michael St. Laurent, Carl Trypaluk, Dale Unruh, Orlan Wilhite NOAA, National Weather Service, Silver Spring, Maryland PF_tabular PF_graphical Maps_&_aerials PF tabular PDS-based point precipitation frequency estimates with 9% confidence intervals (in inches) 1 Duration -min 1-min 1-min 3-min 6-min 2-hr 3-hr 6-hr 12-hr 24-hr 2-day 3-day 4-day 7-day 1-day 2-day 3-day 4-day 6-day Average recurrence interval (years) ( ).473 ( ).6 ( ).763 ( ).969 ( ) 1.23 ( ) 1.42 ( ) 1.82 ( ) 2.3 ( ) 2.73 ( ) 3.4 ( ) 3.28 ( ) 3.2 ( ) 4.22 ( ) 4.89 ( ) 6.89 ( ) 8.3 ( ) 1. ( ) 12.2 ( ).41 ( ).68 ( ).669 ( ).917 ( ) 1.17 ( ) 1.49 ( ) 1.72 ( ) 2.21 ( ) 2.8 ( ) 3.36 ( ) 3.8 ( ) 4.1 ( ) 4.36 (3.-.33).1 ( ).8 ( ) 7.87 ( ) 9. ( ) 11.6 ( ) 13.3 ( ).11 ( ).724 ( ).82 ( ) 1.17 (.96-1.) 1.48 ( ) 1.91 ( ) 2.21 ( ) 2.84 ( ) 3.62 ( ) 4.4 ( ).4 ( ).42 ( ).73 ( ) 6. ( ) 7.3 ( ) 9.48 ( ) 11.2 ( ) 13.3 ( ) 1.1 ( ).63 ( ).84 ( ) 1.1 ( ) 1.38 ( ) 1.7 ( ) 2.2 ( ) 2.61 ( ) 3.37 ( ) 4.3 ( ).2 ( ) 6.7 ( ) 6.2 ( ) 6.87 ( ) 7.7 ( ) 8. ( ) 1.8 ( ) 12.6 ( ) 14.8 ( ) 16.6 ( ).729 ( ) 1.3 ( ) 1.21 ( ) 1.66 ( ) 2.11 ( ) 2.73 ( ) 3.17 ( ) 4.1 ( ).24 ( ) 6.43 ( ) 7.49 ( ) 8.3 ( ) 8.44 ( ) 9.41 ( ) 1.3 ( ) 12.7 ( ) 14. ( ) 16.8 ( ) 18.6 ( ).826 ( ) 1.17 ( ) 1.38 ( ) 1.89 ( ) 2.39 ( ) 3.1 ( ) 3.6 ( ) 4.66 ( ).96 ( ) 7.34 (.-9.89) 8.8 ( ) 9.2 ( ) 9.64 ( ) 1.7 ( ) 11.6 ( ) 14.1 ( ) 16. ( ) 18.3 ( ) 2.2 ( ).922 ( ) 1.31 ( ) 1.4 ( ) 2.11 (1.-3.1) 2.68 ( ) 3.47 ( ) 4.3 ( ).22 ( ) 6.69 ( ) 8.2 ( ) 9.67 ( ) 1.4 ( ) 1.9 ( ) 12. ( ) 12.9 ( ) 1. ( ) 17. ( ) 19.8 ( ) 21.7 ( ) 1 Precipitation frequency (PF) estimates in this table are based on frequency analysis of partial duration series (PDS). 1.4 ( ) 1.48 ( ) 1.74 ( ) 2.38 ( ) 3.2 ( ) 3.99 ( ) 4.67 ( ) 6.8 ( ) 7.77 ( ) 9.64 ( ) 11.4 ( ) 12.3 ( ) 12.8 ( ) 13.9 ( ) 14.8 ( ) 17.2 ( ) 19.1 ( ) 21.2 ( ) 23. ( ) 1.2 ( ) 1.7 ( ) 2.1 ( ) 2.74 ( ) 3.48 ( ) 4.67 ( ).2 ( ) 7.21 ( ) 9.21 ( ) 11. ( ) 13.8 ( ) 14.8 ( ) 1.4 ( ) 16. ( ) 17.3 ( ) 19. ( ) 21.2 ( ) 23.1 ( ) 24.6 ( ) 1.32 ( ) 1.88 ( ) 2.21 ( ) 3.2 ( ) 3.83 ( ).19 ( ) 6.1 ( ) 8.6 ( ) 1.3 (6.9-1.) 12.9 ( ) 1.6 ( ) 16.7 ( ) 17.3 ( ) 18.4 ( ) 19.2 ( ) 21.2 ( ) 22.7 ( ) 24. ( ) 2.8 ( ) Numbers in parenthesis are PF estimates at lower and upper bounds of the 9% confidence interval. The probability that precipitation frequency estimates (for a given duration and average recurrence interval) will be greater than the upper bound (or less than the lower bound) is %. Estimates at upper bounds are not checked against probable maximum precipitation (PMP) estimates and may be higher than currently valid PMP values. Please refer to NOAA Atlas 14 document for more information. Back to Top PF graphical

170 Precipitation Frequency Data Server Page 2 of 4 6/8/216 Back to Top Maps & aerials Small scale terrain km Map data 216 Google

171 Precipitation Frequency Data Server Page 3 of 4 6/8/216 2 km Map data Report 216 a map Google error Large scale map 2 km Map data Report 216 a map Google error Large scale aerial 2 km Imagery 216 Report TerraMetrics a map error Back to Top US Department of Commerce National Oceanic and Atmospheric Administration National Weather Service National Water Center 132 East West Highway Silver Spring, MD 291

172 Precipitation Frequency Data Server Page 4 of 4 6/8/216 Questions?: HDSC.Questions@noaa.gov Disclaimer

173 HYDROLOGIC/HYDRAULIC ANALYSIS REPORT FOR THE TROLLEY BROOK CULVERT ASHLAND, MA APPENDIX G TROLLEY BROOK CULVERT PLAN AND PROFILE

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177 HYDROLOGIC/HYDRAULIC ANALYSIS REPORT FOR THE TROLLEY BROOK CULVERT ASHLAND, MA APPENDIX H OBSERVATION PHOTOS

178 Trolley Brook Culvert, Ashland Observation Photos Trolley Brook looking upstream from inlet Culvert inlet with bars off Megunko Road

179 Trolley Brook Culvert, Ashland Observation Photos Small manholes and connecting drain pipes extend into trunck lines reducing capacity

180 Trolley Brook Culvert, Ashland Observation Photos 4 x4 stone box culvert 36 HDPE Pipe

181 Trolley Brook Culvert, Ashland Observation Photos 4 x4 stone box culvert outlet