Supervisors' support reduces Winter Haven Road speed limit

The San Diego County Board of Supervisors provided support for the reduction of the speed limit on Winter Haven Road between South Mission Road and Brooke Road.

A 5-0 vote Wednesday, Oct. 16, approved the introduction and first reading of the ordinance amendment to reduce the speed limit from 45 mph to 40 mph. The second reading and adoption is scheduled for Oct. 30, and that approval would make the new speed limit effective Nov. 29.

In order for a speed limit to be enforceable by radar, a speed survey must show that the speed limit is within an adjacent 5 mph increment to the 85th percentile speed. Periodic recertification, including a supporting speed survey, is required for continued radar enforcement and the county’s Department of Public Works or a department contractor typically conducts speed surveys every seven years. The speed limit may be rounded either up or down from the 85th percentile speed. The speed limit may also be rounded down an additional 5 mph if findings are made that the road has conditions which would not be apparent to a motorist unfamiliar with the road.

Winter Haven Road between South Mission Road and Brooke Road measures 0.70 miles. The travel width of that part of Winter Haven Road ranges from 20 to 24 feet while the road bed width ranges between 24 and 48 feet. The street is striped with a double yellow center line and white edge striping. Winter Haven Road is not classified on the mobility element of the county’s general plan.

A traffic survey east of South Mission Road was taken May 15, 2019, to determine an average daily volume of 5,715 vehicles. That total consists of 2,898 eastbound and 2,817 westbound motorists.

The highest hourly volumes of the traffic survey were 610 vehicles from 7-8 a.m., 482 motorists from 3-4 p.m. and 456 drivers from 2-3 p.m.

The previous traffic survey for that portion of Winter Haven Road was taken in February 2012 and resulted in an average daily volume of 5,200 vehicles.

During the 36-month period from Feb. 1, 2016, to Jan. 31, 2019, Winter Haven Road between South Mission Road and Brooke Road had six reported collisions. Two of those were at the intersection of Winter Haven Road and Clearcrest Lane and were within a 10-day period of each other; the June 23 collision was caused by unsafe speed and resulted in one injury and driving under the influence caused two injuries July 2. A February 2016 collision at the intersection of Winter Haven Road and Buena Flores was caused by improper turning and did not involve injury. Unsafe starting and backing caused the January 2017 non-injury collision east of South Mission Road. A June 2018 collision just west of Buena Rosa was caused by improper turning, did not involve injury and was the only night collision among the six. Improper passing was responsible for an August 2018 collision east of South Mission Road which caused one injury. The six collisions gave that part of Winter Haven Road a collision rate of 1.41 per million vehicle miles. The statewide average for similar suburban conventional two-lane roads with speed limits of 45 mph or less is 1.19 per million vehicle miles.

The 45 mph speed limit was based on a 2012 speed survey 150 feet west of Clearcrest Lane which had an 85th percentile of 47.0 mph with 62.9% of the drivers within a 10 mph pace of 34-44 mph. A May 9, 2019, speed survey at that location was taken between noon and 2 p.m. and the 382 vehicles had an 85th percentile speed of 44.5 mph with 59% within a 37-46 mph pace. The fastest speeds were 60 mph, 56 mph and 55 mph with one motorist apiece while the slowest driver crossed the survey point at 22 mph and the next-slowest was traveling at 24 mph. The most frequent speeds were 41 mph with 32 vehicles, 38 mph with 31 drivers, 39 mph with 30 motorists, 37 mph with 26 drivers and 33 mph with 25 vehicles.

The county’s Traffic Advisory Committee unanimously recommended the reduced speed limit during the TAC’s July 26 meeting.