Inter-Departmental Correspondence

Department of Public Works



August 25, 2010


September 14, 2010







Honorable Board of Supervisors


James C. Porter, Director of Public Works


Decrease Speed Limit on Parrott Drive, San Mateo Highlands Area



Adopt an Ordinance authorizing a prima facie speed limit of 25 miles per hour for the County-maintained portion of Parrott Drive, San Mateo Highlands Area.



California Vehicle Code Section 22352 assigns a prima facie speed limit of 25 miles per hour to streets in residence districts, unless local authority determines a different speed limit is appropriate.



The Department of Public Works currently has a posted speed limit of 30 miles per hour (mph) in a section of Parrott Drive approximately located between Los Altos Drive and 1,800 feet north of Bel Aire Road in San Mateo Highlands. Several residents along Parrott Dr. requested that something be done to reduce the speed on their street.


In response to the public, Public Works staff determined that the current posted speed limit is no longer appropriate for this section of road. The density of houses in this area classifies it as a “Residence District,” defined in California Vehicle Code (CVC) Section 515. According to CVC Section 22352, the prima facie speed limit for a “Residence District” should be 25 mph, unless otherwise posted. Staff believes the proposed reduction is a necessary step to accommodate the needs of the community.


Property owners on adjacent blocks extending a minimum of 300 feet from the proposed speed limit reduction locations were notified of the date and time of the Board’s meeting when these items will be considered. In addition, the California Highway Patrol, the City of San Mateo, and the Town of Hillsborough were likewise notified. In addition to three public requests for this speed limit reduction, six property owners are in support, and two property owners are opposed. A summary of the public input we received regarding this issue is included in Attachment “A.”


The location of signs on County maintained streets are shown on maps in the Department of Public Works, and will be made available in list form on the Department’s web site. The master lists will be updated to reflect the recommended changes if your Board approves the proposed resolution.


Approval of the speed limit reduction will contribute to the Shared Vision 2025 outcome of a Livable Community by providing traffic controls that help regulate the traffic flow through neighborhoods in a way that best fits the needs of the community.


County Counsel has reviewed and approved the proposed Ordinance as to form.



The cost for staff time involved in evaluating and processing requests for traffic regulations is part of the administrative cost associated with evaluating traffic-related requests involving the County maintained road system, and is financed with Road Funds. The cost to replace four 30 MPH signs with four 25 MPH signs is approximately $600, which will be financed with Road Funds. There will be no impact to the General Fund.



Attachment “A” – Map of Proposed Traffic Control Device Locations and Public Input Summary