Memorandum. To: Sue Polka, City Engineer, City of Arden Hills. From: Sean Delmore, PE, PTOE. Date: June 21, 2017

Transcription

1 Memorandum engineering planning environmental construction 701 Xenia Avenue South Suite 300 Minneapolis, MN Tel: Fax: To: Sue Polka, City Engineer, City of Arden Hills From: Sean Delmore, PE, PTOE Date: June 21, 2017 Re: Intersection Study at Chatham Avenue and McCracken Lane Introduction The City of Arden Hills has received complaints about the safety of school children at the intersection of Chatham Avenue and McCracken Lane. The purpose of this study was to: 1. Document the steps taken to evaluate the need for additional traffic control. This includes a Thru- Stop and All-Way Stop control. 2. Evaluate any concerns with the bus stopping including driver behavior when a bus is stopped at this intersection. Existing Conditions The intersection consists of two urban local streets in the city of Arden Hills. Currently, the intersection is uncontrolled and has a low volume of traffic. McCracken Lane has a posted speed limit of 30 MPH and Chatham Avenue has an unposted (statutory) speed limit of 30 MPH. Refer to Figure 1 in Appendix A for the study location. According to Mounds View public schools, a total of 12 school buses are scheduled to run daily through this intersection. The bus stop times and routes are presented in Appendix B. Data Collection Two video cameras were installed at the intersection of Chatham Avenue and McCracken Lane to collect existing AM and PM peak hour volumes from Tuesday, June 6, 2017 to Thursday, June 8, The AM peak hour begins at 7:00 AM and the PM peak hour begins at 4:00 PM. This count data is provided in Appendix C. The video cameras also provided documentation of driver behavior when school busses were stopped during pickup and drop-off times. Equal Opportunity Employer wsbeng.com

2 Stop Sign Memo June 21, 2017 Page 2 Intersection Evaluation The intersection of Chatham Avenue and McCracken Lane was evaluated for an All-Way Stop control based on the Minnesota Manual of Uniform Traffic Control Devices (MnMUTCD). An All-Way Stop warrant analysis was completed using the MnDOT warrant template. MnMUTCD According to section 2B.7 of the MnMUTCD, the decision to install a Multi-Way Stop control (All-Way Stop in this case) should be based on an engineering study. The following criteria should be considered in the engineering study for a Multi-Way Stop sign installation: A. Where traffic control signals are justified, the Multi-Way Stop is an interim measure that can be installed quickly to control traffic while arrangements are being made for the installation of the traffic control signal. A traffic signal is not justified at this intersection. B. Five or more reported crashes in a 12-month period that are susceptible to correction by a Multi- Way Stop installation. Such crashes include right-turn and left-turn collisions as well as rightangle collisions. A review of MnDOT s accident database (Minnesota Crash Mapping Analysis Tool, MnCMAT) over the past 3 years ( ) revealed that no crashes were documented at this intersection. C. Minimum Volumes 1. The vehicular volume entering the intersection from the major street approaches (total of both approaches) averages at least 300 vehicles per hour for any 8 hours of an average day. At this intersection, there were no hours during the day that meet criteria C.1. Less than 150 vehicles enter the intersection during the PM peak hour, and less than 100 enter during the AM peak hour. These volumes are significantly less than the required minimum volumes for an All- Way Stop control. See the attached All-Way Stop warrant spreadsheet in the Appendix D. 2. The combined vehicular, pedestrian, and bicycle volume entering the intersection from the minor street approaches (total of both approaches) averages at least 200 units per hour for the same 8 hours, with an average delay to minor-street vehicular traffic of at least 30 seconds per vehicle during the highest hour; but At this intersection, there were no hours during the day that meet criteria C.2. See the attached All-Way Stop warrant spreadsheet in Appendix D. G:\Group Data\Traffic\Arden Hills\Chatham Ave & Mccraken Ln\Arden Hills Stop Sign Request Memo.doc

3 Stop Sign Memo June 21, 2017 Page 3 3. If the 85th percentile approach speed of the major street traffic exceeds 40 MPH, the minimum vehicular volume warrant is 70 percent of the above values. A speed study was not performed at this intersection, but both roads currently have at speed limit of 30 MPH and 85 th percentile speeds exceeding 40 MPH would not be expected. Where no single criterion is satisfied, but where criteria B, C.1, and C.2 are all satisfied to 80 percent of the minimum values. Criterion C.3 is excluded from this condition. Criteria B, C.1, and C.2 are not satisfied to 80 percent of the original minimum values stated previously. D. Pedestrian Volumes Pedestrian volumes at this intersection are assumed to be higher than normal for a residential neighborhood. This is mostly related to the children crossing to or from the school bus stops. During the AM peak hour, seven pedestrians were counted within the intersection. During the PM peak hour, eight pedestrians were present. There are no sidewalks within the intersection quadrant, and no pedestrian signs are posted nearby. F. Sight Distance 1 Exhibit 9-51 (Table 1) from AASHTO s Geometric Design of Highways and Streets displays the sight distance travel by an approaching vehicle as a function of the design speed of the roadway on which the uncontrolled intersection approach is located. Based on the speed limit of 30 MPH for both Chatham Avenue and McCracken Lane, 140 feet of sight distance is needed to safely permit the vehicles on either road to stop, if necessary, before reaching the intersection. The existing geometry does not currently provide adequate sight lines for an uncontrolled intersection. However, low volumes on these roadways combined with the current travel patterns for most vehicles, has resulted in very few conflicts at the intersection with no recorded crashes. Table 1. Sight Distances Based on Design Speeds 1 Based on procedures and values found in A Policy on Geometric Design of Highways and Streets (2004) by the American Association of State Highway and Transportation Officials (AASHTO). G:\Group Data\Traffic\Arden Hills\Chatham Ave & Mccraken Ln\Arden Hills Stop Sign Request Memo.doc

4 Stop Sign Memo June 21, 2017 Page 4 Driver Behavior versus Stopped School Bus Based on the video data analysis, the following observations were found: Out of the 12 school busses scheduled to stop at/travel through the intersection of Chatham Avenue and McCracken Lane, only four busses stopped to pickup/drop-off children. The other busses did not stop or did not show. On Tuesday June 6, 2017: Two school busses stopped at the intersection (9:05 AM, and 4:15 PM). No vehicle interaction with busses was observed. On Wednesday June 7, 2017: Four school busses stopped at the intersection (6:56 AM, 9:05 AM, 2:18 PM, and 4:15 PM). For the school bus stop at 9:05 AM, the vehicle approaching the intersection stopped until the school bus left (no apparent danger). Other busses had no vehicle interaction. On Thursday June 8, 2017: three school busses stopped at the intersection (6:56AM, 9:05AM, and 4:15 PM). No vehicle interaction with busses was observed. From the video, it was noted that children and parents were standing in the road while waiting for the bus. This stop corresponds to the right corner of McCracken Lane coming from the east leg of the road. Figure 1 in Appendix A shows this stop location denoted as Stop Bus 1. Figure 1 in the Appendix A also shows the location of these stops and the corresponding bus stop times. CONCLUSIONS Based on the information contained in this document from the video data collected and engineering judgment, the following conclusions have been drawn: This intersection appears to be operating well despite the sight distance issues and the fact that it is currently uncontrolled. Typically, a location with this type of activity would be controlled as a Thru-Stop. According to the MnMUTCD, an All-Way Stop control is not warranted at this intersection. Stop signs are recommended for Northbound and Southbound of Chatham Avenue to better define right of way at the intersection with minimal additional delay. G:\Group Data\Traffic\Arden Hills\Chatham Ave & Mccraken Ln\Arden Hills Stop Sign Request Memo.doc

5 Stop Sign Memo June 21, 2017 Page 5 APPENDIX A. Existing Intersection Location, Geometry, and Peak-Hour Turning Movements B. School District Bus Stops/Routes C. Turning Movement Counts D. All-Way-Stop Warrant G:\Group Data\Traffic\Arden Hills\Chatham Ave & Mccraken Ln\Arden Hills Stop Sign Request Memo.doc

6 APPENDIX A Existing Intersection Location, Geometry, and Peak-Hour Turning Movements G:\Group Data\Traffic\Arden Hills\Chatham Ave & Mccraken Ln\Arden Hills Stop Sign Request Memo.doc

7 STUDY LOCATION LEGEND ; 5 (24) 248 Lane Geometry Peak AM (PM) Turning Movements Turning Movement Bus Stop 1 Times: 9:05 AM Bus Stop 2 Times: 6:56 AM, 2:18 PM, 4:15 PM Figure 1 Chatham Avenue & McCraken Lane Intersection Existing Intersection Location, Arden Hills, Ramsey, Minnesota Geometry, and Peak-Hour Turning Movements

8 APPENDIX B Turning Movement Counts G:\Group Data\Traffic\Arden Hills\Chatham Ave & Mccraken Ln\Arden Hills Stop Sign Request Memo.doc

9 WSB & Associates 701 Xenia Ave S Minneapolis, MN Chatham Ave & McCracken Ln 7-9am & 4-6pm Arden Hills, Mn 80's File Name : McCracken Ln & Chatham Ave Site Code : Start Date : 6/7/2017 Page No : 1 Groups Printed- Cars + Chatham Ave From North McCracken Ln From East Chatham Ave From South McCracken Ln From West Start Time Right Thru Left Peds App. Total Right Thru Left Peds App. Total Right Thru Left Peds App. Total Right Thru Left Peds App. Total Int. Total 07:00 AM :15 AM :30 AM :45 AM Total :00 AM :15 AM :30 AM :45 AM Total :00 PM :15 PM :30 PM :45 PM Total :00 PM :15 PM :30 PM :45 PM Total Grand Total Apprch % Total %

10 WSB & Associates 701 Xenia Ave S Minneapolis, MN Chatham Ave & McCracken Ln 7-9am & 4-6pm Arden Hills, Mn 80's File Name : McCracken Ln & Chatham Ave Site Code : Start Date : 6/7/2017 Page No : 2 Chatham Ave From North McCracken Ln From East Chatham Ave From South McCracken Ln From West Start Time Right Thru Left Peds App. Total Right Thru Left Peds App. Total Right Thru Left Peds App. Total Right Thru Left Peds App. Total Int. Total Peak Hour Analysis From 07:00 AM to 11:45 AM - Peak 1 of 1 Peak Hour for Entire Intersection Begins at 08:00 AM 08:00 AM :15 AM :30 AM :45 AM Total Volume % App. Total PHF Chatham Ave Out In Total Right 2 Thru 8 Left 0 Peds Peak Hour Data McCracken Ln Out In Total Left 5 Thru 0 Right 5 Peds Peak Hour Begins at 08:00 AM Cars + North Right Thru Left Peds Out In Total McCracken Ln Left 0 Thru 0 Right 12 Peds Out In Total Chatham Ave

11 WSB & Associates 701 Xenia Ave S Minneapolis, MN Chatham Ave & McCracken Ln 7-9am & 4-6pm Arden Hills, Mn 80's File Name : McCracken Ln & Chatham Ave Site Code : Start Date : 6/7/2017 Page No : 3 Chatham Ave From North McCracken Ln From East Chatham Ave From South McCracken Ln From West Start Time Right Thru Left Peds App. Total Right Thru Left Peds App. Total Right Thru Left Peds App. Total Right Thru Left Peds App. Total Int. Total Peak Hour Analysis From 12:00 PM to 05:45 PM - Peak 1 of 1 Peak Hour for Entire Intersection Begins at 04:00 PM 04:00 PM :15 PM :30 PM :45 PM Total Volume % App. Total PHF Chatham Ave Out In Total Right 2 Thru 2 Left 1 Peds Peak Hour Data McCracken Ln Out In Total Thru Left 0 Right 4 Peds Peak Hour Begins at 04:00 PM Cars + North Right Thru Left Peds Out In Total McCracken Ln Left 1 Thru 0 Right 11 Peds Out In Total Chatham Ave

12 APPENDIX C All-Way Stop Warrant G:\Group Data\Traffic\Arden Hills\Chatham Ave & Mccraken Ln\Arden Hills Stop Sign Request Memo.doc

13 ALL WAY STOP WARRANT Year: 2017 Ex. Condition: No Traffic Control LOCATION: Chatham Avenue & McCraken Lane COUNTY: Ramsey REF. POINT: Speed Approach Description Lanes DATE: 6/15/ Major App1: Chatham Ave (NB) 1 30 Major App3: Chatham Ave (SB) 1 OPERATOR: Edwin 30 Minor App2: McCraken Ln (WB) 1 30 Minor App4: McCraken Ln (EB) FACTOR USED? No MAJOR MAJOR MINOR MINOR MAJOR TOTAL MINOR TOTAL WARRANT HOUR APP. 1 APP. 3 APP. 2 APP. 4 Σ (APP. 1 & APP. 3) APP. 2 + APP. 4 MET 12:00-1:00 AM 1:00-2:00 AM 2:00-3:00 AM 3:00-4:00 AM 4:00-5:00 AM 5:00-6:00 AM 6:00-7:00 AM 7:00-8:00 AM / 8:00-9:00 AM / 9:00-10:00 AM 10:00-11:00 AM 11:00-12:00 PM 12:00-1:00 PM 1:00-2:00 PM 2:00-3:00 PM 3:00-4:00 PM 4:00-5:00 PM / 5:00-6:00 PM / 6:00-7:00 PM 7:00-8:00 PM 8:00-9:00 PM 9:00-10:00 PM 10:00-11:00 PM 11:00-12:00 AM Met (Hr) Required (Hr) Allway Stop Warrant: 0 3 Not satisfied REMARKS:

14 APPENDIX D School District Bus Stops/Routes G:\Group Data\Traffic\Arden Hills\Chatham Ave & Mccraken Ln\Arden Hills Stop Sign Request Memo.doc

15 School District Bus Stops - McCracken Ln at Chatham Ave_ Mounds View High School Bus Stop at 6:56 a.m. 1

16 School District Bus Stops - McCracken Ln at Chatham Ave_ Highview Middle School Bus stop at 7:13 a.m. 2

17 School District Bus Stops - McCracken Ln at Chatham Ave_ Valentine Hills Elementary Bus stop at 9:05 a.m. 3

18 School District Bus Stops - McCracken Ln at Chatham Ave_ Irondale High School Bus stop at 6:44 a.m. (currently inactive) 4

19 School District Bus Stops - McCracken Ln at Chatham Ave_ Mounds View High School Bus Stop at 2:18 p.m. 5

20 School District Bus Stops - McCracken Ln at Chatham Ave_ Irondale High School Bus Stop at 2:31 p.m. 6

21 School District Bus Stops - McCracken Ln at Chatham Ave_ Highview Middle School Bus Stop at 3:16 p.m. 7

22 School District Bus Stops - McCracken Ln at Chatham Ave_ Mounds View High School After School Bus Stop at 3:29 p.m. (sporadic use) (image not available) 8

23 School District Bus Stops - McCracken Ln at Chatham Ave_ Valentine Hills Elementary Bus Stop at 4:15 p.m. 9

24 School District Bus Stops - McCracken Ln at Chatham Ave_ Highview Middle School After School Bus Stop at 4:43 p.m. (sporadic use) 10

25 School District Bus Stops - McCracken Ln at Chatham Ave_ Valentine Hills Elementary After School Bus Stop at 5:13 p.m. (Mondays only) 11

26 School District Bus Stops - McCracken Ln at Chatham Ave_ Mounds View High School After School Bus Stop at 5:07 p.m. (sporadic use) (Image not available) 12