To: MAYOR AND CITY COUNCIL
From: TED SEMAAN, PUBLIC WORKS DIRECTOR
TITLE
title
APPROVE INSTALLATION OF ROADWAY MODIFICATIONS ON ALTA VISTA PARK ACCESS ROAD
end
EXECUTIVE SUMMARY
In response to the Recreation and Parks Commission’s request to address concerns about vehicle speed and safety at Alta Vista Park, staff has evaluated the access road from the park entrance to the intersection of Serpentine Street and Julia Avenue to determine appropriate traffic calming alternatives to enhance safety. The access road is generally used to connect users to/from Alta Vista Park and used for access to-and-from Alta Vista Elementary School. Staff’s observations and data collection efforts have identified potential speed related concerns along this segment. Following presentation to the Public Works Commission, the Commission identified the following alternatives to forward to the City Council to help address speeding concerns and enhance traffic safety:
• Install appropriate 15 mph speed limit signs within Alta Vista Park by preparing an Engineering and Traffic survey,
• Install speed cushions on the Alta Vista Park access road approximately 100’ north of Serpentine Street and;
• Reconstruct the previous speed table on the Alta Vista Park access road (including ADA curb ramp enhancements)
The alternatives were presented to the Public Works Commission at their August 23rd meeting at which time the Commission concurred with staff’s recommendations and voted unanimously (7-0) to consider them appropriate to forward to the City Council for final approval.
BACKGROUND
The Alta Vista Park access road is classified as a local roadway on the current California Road System Functional Classification System maps submitted to the Federal Highway Administration. The study segment runs north-south from the southern limit of Serpentine Street and Julia Avenue to the entrance to Alta Vista Park, approximately 750 feet in length. There are two separate parking lots located adjacent to the access road, one on the west side with the entrance to the lot located approximately 200 feet from Serpentine Street and the other located at the northern terminus of the roadway. Angled parking is available on both sides of the roadway and the posted speed limit is 15 mph when children are present. The Alta Vista Elementary School grounds, on the east side of the segment, extends approximately 110 feet north from the intersection at Serpentine Street and sidewalks are available on both sides of the roadway. There is a stamped crosswalk located approximately midway along the segment as well.
The southerly intersection of Serpentine Street and Julia Avenue is a T-intersection that is all-way stop controlled and marked with a yellow continental crosswalk on all legs.
ANALYSIS:
Speed data on the access road was collected on May 26 and June 1, 2021. The speed data found that the highest speed, average speeds and 85th percentile speeds were 29 mph, 17.8 mph and 22 mph, respectively. Staff also observed that approximately 70% of vehicles were traveling at a speed greater than 15 mph; 24% of vehicles were traveling at a speed greater than 20 mph. Staff reviewed all reported accidents along this segment during a two-year span (2019-available 2021) as well and identified no reported collisions.
Based on a review of field observations and speed assessments, the following modifications were forwarded by the Public Works Commission for the Council’s consideration:
15 MPH Speed Limit
One of the recommendations is to designate a reduced speed limit on the access road. As stated within the California Vehicle Code (CVC) and California Manual on Uniform Traffic Control Devices (CA MUTCD), per Table 2B-101(CA), the state or local authority can determine a 15 mph speed limit on a roadway in a public park. As such, an Engineering and Traffic Survey would be conducted to justify a 15 mph speed limit on the access road. Ultimately, the City Council would authorize a resolution for the 15 mph speed limit.
Speed Table and Speed Cushions
Speed tables are ramped pedestrian crossings spanning the entire width of the roadway. These devices are typically placed midblock where pedestrians generally cross as adjacent marked crosswalks may not be within close proximity. These crosswalks are ramped for vehicles to allow pedestrians to cross at grade with the sidewalk. The elevated crossing also acts as a traffic-calming measure to help reduce potential speeding. The use of a speed table at this location would assist in addressing pedestrian crossing safety and speed reduction. It should be noted, however, that the associated construction costs are not insignificant as ADA-related infrastructure and drainage facilities in the vicinity are likely to need improvements to accommodate the speed table.
Speed cushions are the typical devices used throughout our City to address speed related concerns. They’re generally constructed of rubberized material with wheel gaps to allow for fire engines to traverse through the speed cushions by traveling between the designated gaps and minimally affect response times. For this specific location, the installation of the speed cushions would only be within the existing roadway and will not be installed within the angled parking areas.
Additional information can be found in the Public Works Commission Administrative Report provided as part of Attachment 1.
COORDINATION
The Recreation and Parks Commission liaison has been notified of this item’s inclusion to the agenda for this City Council meeting. In addition, staff participated in the September 13, 2021 Virtual District Meeting for Council District 1, coordinated by Council Member Nehrenheim. During staff’s presentation and subsequent Q&A session, we received positive feedback and general concurrence from the residents in attendance. In addition, if the Council approves the construction of the Project, its completion would be coordinated with the upcoming Alta Vista Sewer Pump Station Project - likely to be constructed once the aforementioned project is completed.
Plans and specifications for the speed cushion and speed table will be submitted for the Council’s approval at a future date.
FISCAL IMPACT
Funding is available in the City’s Traffic Calming Budget. A breakdown of costs to install the proposed traffic calming alternatives, including all necessary signs and pavement markings, are as follows:
• Engineering and Traffic Survey, 15 MPH signs and pavement markings - $1,500
• Design and construction of speed table and speed cushion - $50,000
APPROVED BY:
Joe Hoefgen, City Manager
ATTACHMENTS
• Public Works Commission Meeting June 16, 2020 Administrative Report, Meeting Minutes and Presentation