South Mission Road speed limit from Winter Haven to Pepper Tree reduced to 45 mph

The speed limit on South Mission Road between Winter Haven Road and 880 feet south of Pepper Tree Lane will be reduced from 50 mph to 45 mph.

The San Diego County Board of Supervisors approved the first reading and introduction of the speed limit reduction ordinance which includes recertification for radar enforcement on a 3-0 vote Wednesday, March 13, with Joel Anderson and Terra Lawson-Remer not present. A 4-0 vote Wednesday, April 10, with Lawson-Remer absent, approved the second reading and adoption.

The new speed limit will become enforceable Friday, May 10, although the county’s Department of Public Works can erect signage earlier. The action also recertified the 35 mph speed limit on South Mission Road between Hill Street and 860 feet south of Pepper Tree Lane for radar enforcement.

Due to a change in the boundaries the speed limit on South Mission Road between 860 feet south of Pepper Tree Lane and 880 feet south of Pepper Tree Lane was increased from 35 mph to 45 mph and those 20 feet were also recertified for radar enforcement.

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 DPW or a 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.

The 2.77-mile segment of South Mission Road from 880 feet south of Pepper Tree Lane to Hill Street is a four-lane through highway with a striped median. The segment has both residential and commercial usage and varies in width from 70 to 90 feet. South Mission Road is classified as a Boulevard in the mobility element of the county's general plan.

Two traffic surveys were taken Aug. 10, 2023. The survey 500 feet north of Stage Coach Lane had a 24-hour volume of 21,721 vehicles consisting of 11,199 southbound and 10,522 northbound motorists. The 21,386 drivers 200 feet south of Fallbrook Street made 11,404 southbound and 9,982 northbound trips.

Between July 1, 2020, and June 30, 2023, the portion of South Mission Road from Winter Haven Road to 880 feet south of Pepper Tree Lane had 40 reported collisions including 19 with at least one injury and one with a fatality. It created a collision rate of 1.74 per million vehicle miles; the statewide average for similar suburban divided four-lane roads with a speed limit of 55 mph or less is 1.33 per million vehicle miles.

During that 36-month period 110 reported collisions occurred between 880 feet south of Pepper Tree Lane and Hill Street including 50 injury collisions and two incidents involving fatalities. The segment accident rate for that portion is 2.62 per million vehicle miles.

Three speed surveys were also taken Aug. 10, 2023. The 138 vehicles 300 feet north of Sterling Bridge had an 85th percentile speed of 52.3 mph with 62% driving within a 10 mph pace of 43‑52 mph. The collision history was used to justify the additional 5 mph reduction in the speed limit, and the 45 mph zone also creates a transition between the 35 mph segment and the 50 mph speed limit south of Winter Haven Road.

The speed survey 140 feet south of Clemmens Lane had an 85th percentile of 39.0 mph with 83% of the 109 drivers within a 32-41 mph pace. The 131 vehicles 140 feet north of College Street had an 85th percentile of 36.7 mph with 65% in a 26‑35 mph pace.

The Oct. 27 meeting of the county’s Traffic Advisory Committee included a recommendation to reduce the speed limit on South Mission Road from Winter Haven Road to 880 feet south of Pepper Tree Lane to 35 mph and to recertify that segment for radar and to retain and recertify for radar the 35 mph speed limit on South Mission Road from 860 feet south of Pepper Tree Lane to Hill Street.

Joe Naiman can be reached by email at [email protected].