By Joe Naiman
For The Alpine Sun
The 45 mph speed limit on a 3,000-foot stretch of Alpine Heights Road has been recertified for radar enforcement.
A 4-0 San Diego County Board of Supervisors vote January 7, with Greg Cox attending to California Coastal Commission matters, recertified the speed limit on Alpine Heights Road from South Grade Road to 3,000 feet west of South Grade Road.
By Joe Naiman
For The Alpine Sun
The 45 mph speed limit on a 3,000-foot stretch of Alpine Heights Road has been recertified for radar enforcement.
A 4-0 San Diego County Board of Supervisors vote January 7, with Greg Cox attending to California Coastal Commission matters, recertified the speed limit on Alpine Heights Road from South Grade Road to 3,000 feet west of South Grade Road.
In order for a speed limit to be certified for radar enforcement, a speed survey must show that the speed limit is within an adjacent 5 mph increment to the 85th percentile speed. Periodic recertification, along with a supporting speed survey, is required for continued radar enforcement.
The county’s Department of Public Works or DPW contractors conduct speed surveys every seven years on road segments which have been certified for radar enforcement. The speed limit may be rounded either up or down from the 85th percentile speed.
The speed limit on Alpine Heights Road was first posted in 2008, and the road segment was certified for radar at that time. The 2008 speed survey indicated an 85th percentile speed of 46.8 mph with 55.6 percent of drivers traveling within a 10 mph pace of 37-46 mph.
Alpine Heights Road ranges in width from 23 to 31 feet and has both edge striping and median striping. The road is not classified in the Mobility Element of the county’s general plan. In October 2006 a traffic survey 350 feet east of Tompau Place indicated a two-way average daily volume of 1,780 vehicles.
During a five-year period from March 30, 2009, to March 31, 2014, three collisions were reported along that segment of Alpine Heights Road including one which involved injuries.
An updated speed survey was taken on June 26, 2014, and a new traffic survey was conducted in July 2014. The traffic survey produced a two-way average daily volume of 2,350 vehicles.
The speed survey was also conducted 350 feet east of Tompau Place. Between 9:00 a.m. and 11:00 a.m. on June 26, 251 vehicles crossed that location. The 85th percentile speed was 44 mph with 74.0 percent of drivers traveling within a 35-44 mph pace. The most common speed, with 29 drivers, was 38 mph while 25 drivers apiece traveled at 40 mph and 41 mph. A motorist driving 53 mph was the fastest during the two-hour period while the slowest driver crossed the survey point at 30 mph.
The county’s Traffic Advisory Committee reviewed the data on September 12. Although the speed survey results could have supported a 40 mph speed limit enforceable by radar, the TAC noted that Alpine Heights Road is a rural residential roadway and the 45 mph speed limit is reasonable and reflective of the road’s operating conditions.
