FINAL UTILITY REPORT Eastcreek Farm Thornton, CO

Transcription

1 FINAL UTILITY REPORT Eastcreek Farm Thornton, CO October 14, 2016 JN: Prepared for: York 80, LLC st Street Eastelake, CO P: Prepared by: Jansen Strawn Consulting Engineers 45 W. 2nd Avenue Denver, CO P: F: Thomas C. Jansen, PE No Principal solutions. partnerships. success. t f West 2nd Avenue, Denver, Colorado

2 Eastcreek Farm October 14, 2016 Page 2 City of Thornton Development Engineering Division 9500 Civic Center Drive Thornton, CO Attn: Tim Semones Dear Mr. Semones: The purpose of this letter in to present the final design for the proposed water and sanitary utilities within the Eastcreek Farm Subdivision development. The attached report defines and analyzes the impact on the existing public water and sewer systems and the size of the facilities included in the Eastcreek Farm Subdivision development. Water and sanitary demands were calculated for the proposed Single Family Detached Residential areas. Upon analyzing the sanitary sewer demands for the total development, the flow within the proposed 8 sanitary sewer never surpasses the 50% design capacity of 0.38 cfs per City of Thornton Criteria (See report and Appendix to follow). Similarly, the water system for the total development has been analyzed for the scenarios required by City of Thornton Criteria including: Average Day, Maximum Day, Maximum Hour and Maximum Day plus Fire. In all cases, the pipe pressures and velocities were all within the guidelines set by the City of Thornton. Should you have any questions or comments, please feel free to contact me at (303) Sincerely, Jansen Strawn Consulting Engineers, Inc. Tom Jansen, PE Project Manager t f West 2 nd Avenue, Denver, Colorado

3 Eastcreek Farm October 14, 2016 Page 3 CERTIFICATIONS York 80, LLC hereby certifies that the utilities (water and sanitary sewer) for the Eastcreek Farm Subdivision will be constructed to the design presented in this report. I understand that the City of Thornton does not and shall not assume liability for the utilities designed and/or certified by my engineer. I understand that the City of Thornton reviews utility plans but cannot, on behalf of the Eastcreek Farm Subdivision guarantee that final utility design review will absolve York 80, LLC and/or their successors and/or assigns of future liability for improper design. I further understand that approval of the Final Plan and/or Final Development Plan does not imply approval of my engineer s utility design. Attest: Name of Responsible Party Notary Public Authorized Signature I hereby certify that this report (plan) for the Final Utility design of the Eastcreek Farm Subdivision was prepared by me (or under my direct supervision) in accordance with the provisions of the City of Thornton Standards and Specifications for the Responsible Parties thereof. I understand that the City of Thornton does not and will not assume liability for utilities designed by others. Thomas C. Jansen, PE State of Colorado Registration No For and on behalf of Jansen Strawn Consulting Engineers, Inc. Date t f West 2 nd Avenue, Denver, Colorado

4 Eastcreek Farm October 14, 2016 Page 4 T A B L E O F C O N T E N T S INTRODUCTION... 4 I. GENERAL LOCATION AND DESCRIPTION... 4 II. EXISTING UTILITIES... 5 III. PROPOSED UTILITIES... 5 IV. REFERENCES... 7 APPENDIX A Vicinity Map APPENDIX B Sewer Calculations APPENDIX C WaterCAD Map A P P E N D I C E S t f West 2 nd Avenue, Denver, Colorado

5 Eastcreek Farm October 14, 2016 Page 5 I. GENERAL LOCATION AND DESCRIPTION A. Location The proposed Eastcreek Farm Subdivision (site) is located in the southwest quarter section of Section 28, Township 1 South, Range 67 West of the 6 th Principal Meridian, City of Thornton, County of Adams, Colorado. The overall Conceptual Site Plan area currently includes approximately acres of property, including acres of single family detached residential and acres of open space/parks. The site lies to the south of E 470 Right of Way, to the east of York Street and is slightly split by East 152 nd Avenue. The site is bordered to the east by RTD railroad tracks. Adjacent developments include The Haven at York Street Filing No. 3, The Haven at York Street Filing No. 4 and Silver Creek Elementary School. There are no other adjacent developments. An irrigation ditch runs through the site from the northeast to the southwest. The site is currently zoned as and will remain zoned as single family detached (SFD). See Appendix A for the Vicinity Map and Appendix C for an Overall Utility Map. B. Description of Property The Eastcreek Farm Subdivision is being platted with the City of Thornton. Ultimately, the Eastcreek Farm Subdivision will be controlled by the Eastcreek Farm Conceptual Site Plan/Overall Development Plan, which is under review by the City of Thornton. The entire Eastcreek Farm Subdivision is approximately 97 acres, which includes open space and 276 residential lots. The site is largely broken into two individual residential areas, which are separated by East 152 nd Avenue. The existing site is undeveloped land covered by short native grasses. An existing irrigation ditch referred to as German Ditch runs through the site in the southeast. The ditch continues in the southwest portion of the development and acts as a border running to the south site. There is another draingeway running onto the site on the western side, to the north of East 152 nd Ave. Existing slopes run generally to the northeast between 1 and 4%. II. EXISTING UTILITIES A. Potable Water System Information regarding existing water facilities have been gathered from the City of Thornton. According to their records, the subject property is located within Pressure t f West 2 nd Avenue, Denver, Colorado

6 Eastcreek Farm October 14, 2016 Page 6 Zone 1C. This zone has a Hydraulic Grade Line (HGL) of The site elevations range from 5146 to 5111 that correspond to a static pressure of 83 psi and 68 psi. An existing 16-inch water main currently runs within York Street to the west of the site, with a connection into Street B on the proposed site. There is additionally an existing 12 main within East 152 nd Avenue which will have 3 taps off, with two running to the north and one to the south. All of these connections are off of Zone 1C Waterlines. B. Sanitary Sewer The Eastcreek Farm Subdivision is located in Basin H of the Water and Wastewater Master Plan for the City of Thornton. The northeast portion of the site will be serviced from an existing 15-inch sewer main to the northeast of the proposed site. The southwest portion of the site will be serviced by an existing 8-inch sanitary main in East 152 nd Avenue. The existing site has no sanitary demand. The surrounding land uses have been described above, and the proposed sanitary system will be designed in accordance with all City of Thornton Criteria. All proposed land uses comply with what is shown on the City of Thornton Future Land Use Map provided in the Wastewater Masterplan. III. PROPOSED UTILITIES A. Potable Water System The existing water stubs from York and East 152 nd Avenue will have 8-inch waterlines constructed off of them. The waterlines will be interconnected running through the entire site. There will also be a proposed connection between the existing stubbed water main in East 152 nd Avenue running west to the intersection of 152 nd and Street A/M, at which point the lines will run both north and south from that location. All proposed fire hydrants and water service connections will be made off of the proposed looped water mains. All fire hydrants connections will be 6 ductile iron pipe. A WaterCAD model was prepared for this development utilizing City of Thornton criteria and the following scenarios within Zone 1C. Although this water system technically connects different zones, it has been analyzed based upon the immediate zone it has been located in. Zone delineations should not be affected based on the results of this report and were included within the City of Thornton Masterplan. nodes have been placed throughout the site; each node has been assigned a demand based on the number of adjacent units and the criteria referenced earlier in this report. The WaterCAD model accounts for the three different proposed development types. The residential density for the single-family attached has been calculated using the maximum dwelling units per acre of 12 and 2.45 persons per unit. The single-family detached residential will have a calculated dwelling units per acre of 3.3 and 3.45 persons per units. The commercial t f West 2 nd Avenue, Denver, Colorado

7 Eastcreek Farm October 14, 2016 Page 7 development will be divided into their building type based on CSP for the proposed development. Average Day - Max Pressure=100 psi, Min Pressure=50 psi Max Daily + Fire Flow - Min Pressure=20 psi, Max Velocity=11.2 fps Peak Hour - Min Pressure = 40 psi, Max Velocity=5 fps Fire Flow Rate = 1,500 gpm Design criteria used is as follows: 3.45 persons per dwelling Average Day = 150 gallons per person per day Maximum Monthly = 1.8 x Average Day Maximum Daily = 3.2 x Average Day (Residential) Maximum Daily = 1.8 x Average Day (Commercial) Maximum Hourly = 5.76 x Average Day (Residential) Maximum Hourly = 3.24 x Average Day (Commercial) WaterCAD scenarios have been prepared in accordance with City of Thornton Criteria. The scenarios run for the project include Average Day, Maximum Day, Maximum Hour and Maximum Day plus Fire. Spreadsheets have been provided within the appendix detailing the pipe flows, velocities and pressures at junctions called out within the WaterCAD plan sheet. Pipe sizes and materials have all been provided within the WaterCAD pipe spreadsheets. The pressures and pipe velocities are all within the City of Thornton Criteria. No revisions are required based on the findings of the WaterCAD model provided. B. Sanitary Sewer The Eastcreek Farm Subdivision proposed 8-inch gravity sanitary sewer systems running throughout both sides of the proposed single-family detached residential portions of the proposed site. The southwestern portion of the site will be serviced by a proposed sere main running north to East 152 nd Aven, and west, connecting into the existing 8-inch sanitary sewer within East 152 nd Aven to the west of the site. The entire northeastern portion of the site will flow through a proposed sanitary system which is looped through to site, ultimately tying into the existing sanitary sewer to the northeast of the site. The sanitary sewer design has been broken into the two planning areas described above, with the northeast portion of the site being referred to as PA1 in the calculations, with the southwest section to the south of East 152 nd Ave being referred to as PA2. t f West 2 nd Avenue, Denver, Colorado

8 Eastcreek Farm October 14, 2016 Page 8 The sanitary sewer has been designed to meet City of Thornton Standards and Specifications. Criteria used is as follows: 2.45 persons per dwelling Average Day (F) = 80 gallons per person per day Peaking factor = 1.72 / (F ) [3.5 max, 2.0 min] Design Slope for 8 pipe between 0.40% and 5.00% Velocity between 2 and 10 feet per second Design capacity for pipes smaller 15 = 50% maximum capacity results are as follows: Average Day : o PA1 = 45,472 GPD o PA2 = 8,624 GPD Peak from Development o PA1 = 159,152 GPD (0.25 cfs) o PA2 = 30,184 GPD (0.05 cfs) Assuming a minimum pipe slope of 1.0% for an 8 main and a maximum of 50% depth, the allowable capacity has been calculated to be 0.38 cfs. Meanwhile the maximum capacity of a 8 main at a maximum depth of 50% and a slope of 0.4% is 0.38 cfs. The calculated peak demand for the single-family detached residential development is 0.25 cfs. This demand far less than the maximum per City of Thornton Criteria. t f West 2 nd Avenue, Denver, Colorado

9 Eastcreek Farm October 14, 2016 Page 9 IV. REFERENCES 1. City of Thornton Standards and Specifications for the Design and Construction of Public and Private Improvements, City of Thornton, October t f West 2 nd Avenue, Denver, Colorado

10 APPENDIX A Vicinity Map t f West 2 nd Avenue, Denver, Colorado

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12 APPENDIX B Sewer Calculations Water Calculations t f West 2 nd Avenue, Denver, Colorado

13 East Creek Water Calculations Date: 10/11/2016 Prepared by: MDS Persons/Unit = 3.45 Res Low Density Persons/Unit = 2.45 Res mid Density Average Day = 150 gpdpp Maximum Daily = 1.8 x Average Day (Commercial) Maximum Daily = 3.2 x Average Day (Residential) Maximum Hourly = 3.24 x Average Day (Commercial) Maximum Hourly = 5.76 x Average Day (Residential) Fire = 2000 gpm Number of Average Day Maximum Daily Maximum Hourly Junction units Persons gpd gpm gpd gpm gpd gpm J , , , J , , , J , , , J , , , J , , , J , , , J , , , J , , , J , , , J , , , J , , , J , , , J , , , J , , , J , , , J , , , J , , , J , , , J , , , J , , , J , , , Totals

14 Scenario: Maximum Hour J-19 P-25 J-21 P-21 P-10 J-6 P-18 P-23 8 P-2 J-15 J-14 P17 P-8 16 P- 5 P-1 P-6 P-1 P-12 P-14 J-16 P R-3 R-2 J-2 P-3 J-3 J-1 P-1 R Water Map.wtg 10/11/2016 Bentley Systems, Inc. Haestad Methods Solution Center 27 Siemon Company Drive Suite 200 W Watertown, CT USA Bentley WaterCAD V8i (SELECTseries 6) [ ] Page 1 of 1

15 ID J-1 J-2 J-3 J-6 J-14 J-15 J-16 Label Elevation 5, , , , , , , , , , , , , , ,0 5, , , FlexTable: Junction Table Zone Collection (gpm) Hydraulic Grade 5, , , Pressure (psi) Water Map.wtg 10/11/2016 Bentley Systems, Inc. Haestad Methods Solution Center 27 Siemon Company Drive Suite 200 W Watertown, CT USA Bentley WaterCAD V8i (SELECTseries 6) [ ] Page 1 of 2

16 ID 80 J-19 J-21 Label Elevation 5, , , FlexTable: Junction Table Zone Collection (gpm) Hydraulic Grade Pressure (psi) Water Map.wtg 10/11/2016 Bentley Systems, Inc. Haestad Methods Solution Center 27 Siemon Company Drive Suite 200 W Watertown, CT USA Bentley WaterCAD V8i (SELECTseries 6) [ ] Page 2 of 2

17 P-1 P-2 P-3 P-4 P-5 P-6 P-7 P-8 P-9 P-10 P-11 P-12 P-13 P-14 P-15 P-16 P-17 P-18 P-19 P-20 P-21 P-22 P-23 P-24 P-25 P-26 P-27 P-28 P-29 P-30 Label Length (Scaled) Start Node R-1 J-1 J-2 J-3 R-2 J-6 J-14 J-15 J-16 J-19 J-21 R-3 J-1 J-2 J-3 R-2 J-6 J-14 J-15 J-16 J-19 J-21 Stop Node FlexTable: Pipe Table Diameter (in) Material Hazen-Williams C Flow (gpm) Velocity (ft/s) Water Map.wtg 10/11/2016 Bentley Systems, Inc. Haestad Methods Solution Center 27 Siemon Company Drive Suite 200 W Watertown, CT USA Bentley WaterCAD V8i (SELECTseries 6) [ ] Page 1 of 1

18 ID J-1 J-2 J-3 J-6 J-14 J-15 J-16 Label Elevation 5, , , , , , , , , , , , , , ,0 5, , , FlexTable: Junction Table Zone Collection (gpm) Hydraulic Grade 5, , , , , , , , , , , , , , , , , , Pressure (psi) Water Map.wtg 10/11/2016 Bentley Systems, Inc. Haestad Methods Solution Center 27 Siemon Company Drive Suite 200 W Watertown, CT USA Bentley WaterCAD V8i (SELECTseries 6) [ ] Page 1 of 2

19 ID 80 J-19 J-21 Label Elevation 5, , , FlexTable: Junction Table Zone Collection (gpm) Hydraulic Grade 5, , , Pressure (psi) Water Map.wtg 10/11/2016 Bentley Systems, Inc. Haestad Methods Solution Center 27 Siemon Company Drive Suite 200 W Watertown, CT USA Bentley WaterCAD V8i (SELECTseries 6) [ ] Page 2 of 2

20 P-1 P-2 P-3 P-4 P-5 P-6 P-7 P-8 P-9 P-10 P-11 P-12 P-13 P-14 P-15 P-16 P-17 P-18 P-19 P-20 P-21 P-22 P-23 P-24 P-25 P-26 P-27 P-28 P-29 P-30 Label Length (Scaled) Start Node R-1 J-1 J-2 J-3 R-2 J-6 J-14 J-15 J-16 J-19 J-21 R-3 J-1 J-2 J-3 R-2 J-6 J-14 J-15 J-16 J-19 J-21 Stop Node FlexTable: Pipe Table Diameter (in) Material Hazen-Williams C Flow (gpm) Velocity (ft/s) Water Map.wtg 10/11/2016 Bentley Systems, Inc. Haestad Methods Solution Center 27 Siemon Company Drive Suite 200 W Watertown, CT USA Bentley WaterCAD V8i (SELECTseries 6) [ ] Page 1 of 1

21 ID J-1 J-2 J-3 J-6 J-14 J-15 J-16 Label Elevation 5, , , , , , , , , , , , , , ,0 5, , , FlexTable: Junction Table Zone Collection (gpm) , Hydraulic Grade 5, , , , , , , , , , , , , , , , , , Pressure (psi) Water Map.wtg 10/11/2016 Bentley Systems, Inc. Haestad Methods Solution Center 27 Siemon Company Drive Suite 200 W Watertown, CT USA Bentley WaterCAD V8i (SELECTseries 6) [ ] Page 1 of 2

22 ID 80 J-19 J-21 Label Elevation 5, , , FlexTable: Junction Table Zone Collection (gpm) Hydraulic Grade 5, , , Pressure (psi) Water Map.wtg 10/11/2016 Bentley Systems, Inc. Haestad Methods Solution Center 27 Siemon Company Drive Suite 200 W Watertown, CT USA Bentley WaterCAD V8i (SELECTseries 6) [ ] Page 2 of 2

23 P-1 P-2 P-3 P-4 P-5 P-6 P-7 P-8 P-9 P-10 P-11 P-12 P-13 P-14 P-15 P-16 P-17 P-18 P-19 P-20 P-21 P-22 P-23 P-24 P-25 P-26 P-27 P-28 P-29 P-30 Label Length (Scaled) Start Node R-1 J-1 J-2 J-3 R-2 J-6 J-14 J-15 J-16 J-19 J-21 R-3 J-1 J-2 J-3 R-2 J-6 J-14 J-15 J-16 J-19 J-21 Stop Node FlexTable: Pipe Table Diameter (in) Material Hazen-Williams C Flow (gpm) , , ,121 1, ,160 Velocity (ft/s) Water Map.wtg 10/11/2016 Bentley Systems, Inc. Haestad Methods Solution Center 27 Siemon Company Drive Suite 200 W Watertown, CT USA Bentley WaterCAD V8i (SELECTseries 6) [ ] Page 1 of 1

24 ID J-1 J-2 J-3 J-6 J-14 J-15 J-16 Label Elevation 5, , , , , , , , , , , , , , ,0 5, , , FlexTable: Junction Table Zone Collection (gpm) Hydraulic Grade 5, , ,303. 5,303. 5,303. 5, ,303. 5, ,303. 5, , , , ,303. 5, Pressure (psi) Water Map.wtg 10/11/2016 Bentley Systems, Inc. Haestad Methods Solution Center 27 Siemon Company Drive Suite 200 W Watertown, CT USA Bentley WaterCAD V8i (SELECTseries 6) [ ] Page 1 of 2

25 ID 80 J-19 J-21 Label Elevation 5, , , FlexTable: Junction Table Zone Collection (gpm) Hydraulic Grade 5, , ,303. Pressure (psi) Water Map.wtg 10/11/2016 Bentley Systems, Inc. Haestad Methods Solution Center 27 Siemon Company Drive Suite 200 W Watertown, CT USA Bentley WaterCAD V8i (SELECTseries 6) [ ] Page 2 of 2

26 P-1 P-2 P-3 P-4 P-5 P-6 P-7 P-8 P-9 P-10 P-11 P-12 P-13 P-14 P-15 P-16 P-17 P-18 P-19 P-20 P-21 P-22 P-23 P-24 P-25 P-26 P-27 P-28 P-29 P-30 Label Length (Scaled) Start Node R-1 J-1 J-2 J-3 R-2 J-6 J-14 J-15 J-16 J-19 J-21 R-3 J-1 J-2 J-3 R-2 J-6 J-14 J-15 J-16 J-19 J-21 Stop Node FlexTable: Pipe Table Diameter (in) Material Hazen-Williams C Flow (gpm) Velocity (ft/s) Water Map.wtg 10/11/2016 Bentley Systems, Inc. Haestad Methods Solution Center 27 Siemon Company Drive Suite 200 W Watertown, CT USA Bentley WaterCAD V8i (SELECTseries 6) [ ] Page 1 of 1

27 10/11/2016 Sanitary Calculations for Eastcreek City of Thornton Standards low density (less than 5 DU/acre) 3.45 people / unit mid density (5 to 12 DU/ acre) 2.45 people / unit high density (more than 12 DU/acre) 2.20 people / unit Residential average demand: 80 gal / person / day Commercial average demand: 600 gal / acre DU = dwelling units Planning Area Land Use: DU (ac) People / Unit No. of People Average (gal/person/day) Average Flow (gpd) Average Flow (gpm) Average Flow (cfs) Used Peaking Factor 1 SFA , , SFA , , Peak Flow (gpd) Peak Flow (cfs) Total= 54, , Design Average flow (cfs) Used Peaking Factor Peak Flow (gpd) Peak flow (q) (cfs) Minimum Full Flow Pipe Size (in) Pipe Slope Q full (cfs) Capacity 1 Q cap. (cfs) q/q full (%) (%) (%) 1 45, , % % % 2 8, , % % % 1. Pipes smaller than 15" are designed with no more than 50% maximum flow (q/q) per 2012 City of Thornton Standards and Specs. Page 1 of Sewer s.xlsx

28 APPENDIX C Overall Utility Map t f West 2 nd Avenue, Denver, Colorado

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