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How Are Speed Limits Set?

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For major streets, speed limits are set through an engineering and traffic survey.  For streets that carry local traffic only, the speed limit is set at 25 mph and is not posted.  The purpose of this web page is to publish the engineering and traffic surveys for major streets, prepared and reviewed regularly by the City of San Carlos in accordance with the California Vehicle Code. 

Engineering and traffic surveys measure the actual speeds that drivers travel on a given street.  Certified radar guns are used to ensure that the measurements are accurate.  To the extent possible, the speed measurements are taken on days with fair weather, dry pavement, and clear visibility and are taken at a location not affected by stop signs, parks, schools, curves or other features that would affect speed. An effort is made to ensure that the presence of radar survey equipment did not affect the speed of the traffic being surveyed. After the data on actual speeds has been analyzed, the speed limit is normally set at or below the speed at which 85 percent of drivers are driving.  Speed limits cannot be set arbitrarily low, as this would create violators of the majority of drives and would not command the respect of the public.  

An engineering and traffic survey is to be reviewed five years after it has been completed.  If, at the five year point, the City Engineer finds that conditions have not changed, it does not need to be reviewed for another two years.  If, when the engineering and traffic survey is reviewed seven years after it has been completed, it does not need to be reviewed for another three years.  A new engineering and traffic survey must be completed at the ten year mark.  The table below provides the status of engineering and traffic surveys for all of the major streets in San Carlos.  Follow the links to download the latest engineering and traffic survey and the 5-year or 7-year review. 
 
Street 
(all documents below are in Acrobat PDF format PDF icon)
Last
Surveyed 
Five Year Review Due Per CVC 40802 Have
Conditions
Changed? 
Next Review
Due Per CVC 40802
Alameda de las Pulgas between San Carlos Ave and Redwood City Limits  7/30/2008  7/29/2013   No 7/29/2018 
Brittan Avenue between El Camino Real and Crestview Dr  9/24/2005  9/23/2010   No 9/22/2015 
Brittan Avenue between El Camino Real and US 101  7/30/2008  7/29/2013   No 7/29/2018 
Cedar Street between Belmont City Limits and Eaton Ave  2/18/2011  2/17/2016    
Club Drive between San Carlos Ave and Crestview Dr  5/16/2007  5/14/2012   No  5/14/2014
Cordilleras Avenue between San Carlos Avenue and Emerald Ave  9/24/2005  9/23/2010   No    9/22/2015
Crestview Dr between Edmonds Dr and Brittan Ave  2/18/2011  2/17/2016    
Crestview Dr between Belmont City Limits and Brittan Ave  2/18/2011  2/17/2016    
Devonshire Dr between San Carlos Ave and County Limits  5/16/2007  5/14/2012   No    5/14/2014
Eaton Ave between Oak Creek Ln and Redwood City Limits  9/24/2005  9/23/2010   No    9/22/2015
El Camino Real between Redwood City Limits and Belmont Limits 1/28/2013 1/28/2018    
Elm St between Holly St and Eaton Ave 2/18/2011  2/17/2016    
Holly St between El Camino Real and Elm St  2/20/2006  2/19/2011   No    2/20/2016
Holly St between El Camino Real and Industrial Rd  2/20/2006  2/19/2011   No    2/20/2016
Howard Ave between El Camino Real and Alameda de las Pulgas  2/20/2006  2/19/2011   No   2/20/2016
Howard Ave between El Camino Real and Industrial Rd  2/20/2006  2/19/2011   No       2/20/2016
Industrial Rd between Redwood City Limits and County Limits  10/9/2009  10/8/2014       
Laurel St between Holly St and Eaton Ave  5/16/2007  5/14/2012    No    5/14/2014
Melendy Dr between Alameda de las Pulgas and Club Dr  5/16/2007  5/14/2012   No    5/14/2014
Old County Rd between Redwood City Limits and Belmont City Limits  2/20/2006  2/19/2011   No    2/20/2016
San Carlos Ave between El Camino Real and Belmont City Limits  9/24/2005  9/23/2010   No    9/22/2015
Saint Francis Way between El Camino Real and Alameda de las Pulgas  2/18/2011  2/17/2016
          

For background information on the history, rationale and limitations of setting speed limits, please refer to Special Report 254 from the Transportation Research Board, Managing Speed