Public Works Department
DATE: October 29, 2024
TO: Council Transportation Committee
FROM: Darwin Galang, Senior Traffic Engineer
Lorenzo Lopez, City Traffic Engineer
Quynh Byrer, Acting Assistant Public Works Director/City Engineer
VIA: Edward Arango, Acting Public Works Director
SUBJECT: Neighborhood Traffic Management Program—Wasatch Drive
RECOMMENDATION
Review and recommend the City Council approve the closure of Wasatch Drive at Diericx Drive with a six-month evaluation period starting from the date of installation.
BACKGROUND
In 1996, the City Council adopted the Neighborhood Traffic Management Program (NTMP) to establish a consistent set of guidelines to provide residents and property owners a means to obtain relief from traffic -related concerns, namely speeding vehicles and c ut-through traffic on residential streets. The NTMP process consists of a number of steps that include:
• A request from a neighborhood to initiate the process;
• Verification by the City confirming the road segment is eligible for NTMP program and data collection;
• Community input on which, if any, traffic-calming devices are desired;
• Postcard survey to receive consensus from the residents on the selected devices;
• Council Transportation Committee (CTC) and/or City Council approvals as needed; and
• If approved, installations.
Wasatch Drive is an L -shaped residential street in the Grant Road/Sylvan Park neighborhood located approximately 1,400’ north of Mountain View High School (MVHS) (see Figure 1). It has Neighborhood Traffic Management Program—Wasatch Drive
October 29, 2024
a posted speed limit of 25 miles per hour (mph) and connects to two collector streets: Levin Avenue to the north and Diericx Drive to the east (see Figure 2). Wasatch Drive fronts 24 single- family residential homes, surrounded by similar residential homes.
Figure 1: Neighborhood Area Map
Neighborhood Traffic Management Program—Wasatch Drive
October 29, 2024
Figure 2: Wasatch Drive
In January 2023, the City received multiple complaints from a resident of Wasatch Drive regarding vehicles speeding on Wasatch Drive and using it as a cut-through to bypass the all-way stop sign at Diericx Drive and Levin Avenue, particularly the queuing leading up to the stop sign during school travel times . Over the past years, Wasatch Drive residents had been working with the Police Department (PD) and MVHS staff regarding their concerns with speeding and cut-through traffic. PD and MVHS addressed the neighborhood concerns through targeted enforcement, education, and ongoing field observations. Meanwhile, residents along Wasatch Drive reached out to the Public Works Department to explore other potential solutions due to the recurring concerns over the years.
Neighborhood Traffic Management Program—Wasatch Drive
October 29, 2024
ANALYSIS
Staff conducted vehicle speed and cut -through studies in September 2023 from 6 :00 a.m. to 10:00 p.m. to verify the complaints received . For vehicle speed, staff evaluate s the 85th percentile speed, which is the speed at or below 85% o f d rivers are traveling on a road segment. The results showed that the 85th percentile speed along Wasatch Drive was 32.7 mph, identifying 15% of the vehicles on Wasatch Drive traveled at or above 32.7 mph. The study also identified 87 vehicles out of 125 vehicles (approximately 70%) use d Wasatch Drive as a cut - through street, where 31 vehicles were during the hours of 8:00 a.m. and 8:30 a.m. A street qualifies for the NTMP if it meets either criteria of:
1. Having a posted speed limit of 25 mph with 15% or more vehicles traveling at or above 31 mph; or
2. 25% or more of the traffic using the street as a cut-through.
Both criteria were met; therefore, Wasatch Drive qualifies for the NTMP.
Staff held a neighborhood meeting on February 8, 202 4 where 13 residents attended . The primary concerns shared were the speed of vehicles and the amount of vehicles using Wasatch Drive as a cut-through street. During the meeting, staff presented several proven traffic-calming devices for discussion and recommended the installation of speed humps and/or electronic speed feedback signs. Nearly all attendees were in agreement that their preferred solution was to close Wasatch Drive at Diericx Drive , rather than the staff -recommended measures . Staff identified that a subsequent community meeting would be needed to allow staff time to evaluate the feasibility of a street closure and potential improvement options, if feasible, for the request.
Staff reviewed different alternatives and met with the Fire Department, Recology (the City’s trash and recycling hauler ), and the Solid Waste Section of the Public Works Department to confirm feasibility and identify any operational impacts for the street closure. In summary, City staff and Recology did not have concerns with a street closure as developed by staff so long as it allowed access for their vehicles and equipment. The staff-developed concepts allowed this access.
On May 9, 2024, a second neighborhood meeting was held, and 11 residents attended. City staff presented two alternatives for discussion and consideration. Alternative 1 propose d to close Wasatch Drive at Diericx Drive , and Alternative 2 propose d to close Wasatch Drive at Levin Avenue. Both alternatives address Fire Department and Recology operational needs and include the same treatment measures: rubber curbs, delineator posts, striping, and signage (see Figure 3).
Neighborhood Traffic Management Program—Wasatch Drive
October 29, 2024
Figure 3: Wasatch Drive Closure at Diericx Drive (Concept Only)
All the residents in attendance came to a consensus to close Wasatch Drive at Diericx Drive with the treatment measures staff proposed. If approved, d uring the design phase, the details regarding the spacing of rubber curbs , specific type of flexible knock -down delineators , and striping/signage will be determined to ensure that emergency and trash vehicles can access the street closure area when needed and pedestrian and bicycle access is maintained.
Consistent with the NTMP guidelines, the City conducted a postcard survey of the Wasatch Drive neighborhood residents and property owners in June 2024 identifying the proposed closure. Of the 24 residents and property owners who were mailed the survey, 16 (approximately 67 %) responded, exceeding the 35% response rate required. The survey results are provided below:
Yes No
Votes in Favor—Installation of Proposed Improvements
Closing of Wasatch Drive at Diericx Drive
14 2
(88%) (12%)
Per the NTMP guidelines, for a device to be installed, a supermajority (67%) support of the returned postcard survey is needed, and this was achieved with 88% support . Additionally, the guidelines identify approval by both the Council Transportation Committee (CTC) and City Council are required for street closures.
Further Staff Evaluation
After receiving support for the closure from the postcard survey, staff performed field evaluations to assess the traffic patterns at the Diericx Drive/Levin Avenue intersection during
Neighborhood Traffic Management Program—Wasatch Drive
October 29, 2024
the school year. From late August to mid -September of this year , staff collected data and observed patterns during peak morning traffic times, specifically between 7:45 a.m. and 8:45 a.m. The field evaluations over multiple days revealed a maximum queue of 11 vehicles at the eastbound approach to the Diericx Drive/Levin Avenue intersection happened only once or twice between 8:00 a.m. and 8:30 a.m., and that maximum queue consistently cleared within 90 seconds. The typical queue was between two and six vehicles long during this time frame.
During the same 30-minute window, approximately 100 vehicles were observed turning right from Levin Avenue to Diericx Drive , and approximately 32 vehicles were observed turning right at Wasatch Drive, consistent with the data collected in September 2023. Applying the Wasatch Drive trips to the Levin Avenue/Diericx Drive intersection, staff expects the proposed closure would increase right-turning vehicles from Levin Avenue to Diericx Drive by 30%. With the typical existing queues of two to six vehicles at the Levin Avenue/Diericx Drive intersection and a queue clearance rate within 90 seconds during the maximum observed queue of 11 vehicles , staff anticipates minor added delays at the Levin Avenue/Diericx Drive intersection. During the similar maximum queue length/time frame, an additional 20-second delay may be observed at the Levin Avenue/Diericx Drive intersection due to the add itional vehicle trips diverted as a result of the closure.
Outreach to Residents Along Diericx Drive and Levin Avenue
Recognizing that the closure could add minor queuing to the Diericx Drive/Levin Avenue intersection, staff conducted additional neighborhood outreach specifically to those residents fronting and near th is intersection, where existing queuing is taking place. The Wasatch Drive residents were not included due to staff having held neighborhood meetings with those residents. As part of the neighborhood outreach, letters were sent on September 6 , 2024 to 25 residents on Levin Avenue and Diericx Drive outlining the proposed closure of Wasatch Drive and requesting their feedback and input (see Figure 4).
Neighborhood Traffic Management Program—Wasatch Drive
October 29, 2024
Figure 4: Diericx Drive/Levin Avenue Residents Notified
Eight email responses were received . Staff contacted all eight resident s and spoke to seven of the eight residents to get a better understanding of their concerns. Staff left multiple voicemails for the eighth resident who did not return calls . A summary of the feedback received included the following:
• Frustration over queuing at the Diericx Drive/Levin Avenue intersection and confusion about why traffic was being diverted from Wasatch Drive to their streets.
• Questioning the fairness of using their residential area to resolve traffic issues on Wasatch Drive.
• Concerns about speedin g c aused by the lack of sufficient stop signs and other traffic - calming measures along Diericx Drive and Levin Avenue.
Neighborhood Traffic Management Program—Wasatch Drive
October 29, 2024
• Concerns with noncompliance of existing stop signs.
• Two residents requested traffic -calming measures be applied to Diericx Drive and Levin Avenue.
In response to the feedback received , staff is recommending measures to address these residents’ concerns. Short-term solutions staff will initiate include increased Police enforcement and educational outreach by MVHS staff to students and parents to reduce speeding and improve stop sign compliance. Another proactive element staff will perform includes conducting stop warrant studies at various intersections for possible conversions to all -way stop -controlled intersections. The intersections staff will evaluate for all-way stops include Levin Avenue/Katrina Way, Levin Avenue/Sun-Mor Avenue, and Levin Avenue/Yorkton Drive. Additionally, staff will initiate the NTMP process on Levin Avenue and Diericx Drive without a petition, consistent with the NTMP guidelines due to the diversion of traffic from Wasatch Drive . These efforts aim to prioritize safety and neighborhood feedback.
Demonstration Period (Evaluation)
The NTMP guidelines identify that a demonstration period for some traffic -calming measures could be utilized for a period of one year, including the use of temporary devices to be considered for a trial demonstration of street closures. Since a feasible trial implementation at this location has been develope d and the postcard survey was successful , s taff is recommending a trial demonstration period for the closure of Wasatch Drive with temporary devices of rubber curbs and flexible delineators. In addition, to address the Levin Avenue and Diericx Drive residents’ feedback received regarding the closure of Wasatch Drive, in addition to the measures previously identified, an evaluation period of six months is being recommended versus waiting a full year.
This allows sufficient time for staff to evaluate the project but reduc es the typical trial period to identify how the measures are received by the community.
Per the NTMP guidelines, after the evaluation period, staff will conduct another speed or traffic survey to determine the results of the measures and queuing data at the Levin Avenue/Diericx Drive intersection. Once the results are obtained , three possible actions can be taken and are summarized as follows:
• If the traffic concern has been successfully resolved, queuing increase is minor, and the residents and property owners are satisfied with the results, staff will recommend a permanent installation to the CTC or City Council, pending funding resources.
• If the residents and property owners are unhappy with the installation, even though the traffic study shows the devices have been successful, they may request removal of the device following the Traffic -Calming Device Removal process outlined in the NTMP guidelines.
Neighborhood Traffic Management Program—Wasatch Drive
October 29, 2024
• If the traffic study shows the speed of traffic or the volume of cut -through traffic has not been reduced and queuing is not minor as expected, staff may ask the CTC and/or the City Council for approval to remove the measures. Staff will arrange for another neighborhood meeting to determine if the residents want to consider a different device.
Summary
In summary, staff will continue to coordinate with the PD and MVHS staff for enforcement and education to reduce speeding and improve stop sign compliance. Staff will also conduct stop warrant studies at various locations and will initiate the NTMP process on Levin Avenue and Diericx Drive with neighborhood feedback and support, which may include installation of speed humps or other traffic-calming devices to address speeding concerns.
The closure of Wasatch Drive is feasible with the use of temporary devices, such as rubber curbs, delineator posts, striping, and signage , while maintaining bicycle and pedestrian access . The intent is to demonstrate how these measures will perform and evaluate the street closure six months after the installation. Evaluation will follow the NTMP guidelines and include s staff analyzing any significant changes or safety concerns caused by the closure.
Staff recommends the CTC forward a recommendation to the City Council to approve the closure of Wasatch Drive at Diericx Drive with a six -month evaluation period starting from the date of installation.
NEXT STEPS
If supported by the CTC, staff will request City Council approval in December 2024. If the proposed improvements are approved, staff will finalize design details based on conditions in the field, install the improvements by February 2025, and evaluate the impacts during and after the six-month demonstration period.
Neighborhood Traffic Management Program—Wasatch Drive
October 29, 2024
PUBLIC NOTICING
Notices of this meeting were mailed on October 11, 2024 to the residents and property owners shown in Figure 5 below.
Figure 5: Wasatch Drive Notification Area Map
DG-LL-QB/EA/6/PWK
932-10-29-24M-1
cc: PWD(A), APWD(A)—Byrer, CTE, SCE—Galang