Legal Basis for School Zone & Speed Reduction

Key Provision

"The prima facie limits...shall be as follows and shall be effective when appropriate signs...are erected upon a street or highway:

(b) Fifteen miles per hour:

(1) When traversing a railway grade crossing...or

(2) When traversing an intersection controlled by a traffic officer, stop sign, or traffic signal where visibility is obstructed.

(b)(4) When approaching a school building or the grounds thereof, which are contiguous to a highway and upon which children are present, the prima facie speed limit shall be 25 miles per hour if the highway is posted with a standard "SCHOOL" warning sign."

Key Provision

"Whenever a local authority determines upon the basis of an engineering and traffic survey that the prima facie speed limit...is more than is reasonable or safe, the local authority may...by ordinance or resolution, determine and declare a prima facie speed limit of 60, 55, 50, 45, 40, 35, 30, 25, 20, or 15 miles per hour, whichever is found most appropriate..."

Key Provisions

"(a) Notwithstanding subdivision (b) of Section 22358, a local authority may, by ordinance or resolution, determine and declare a prima facie speed limit of 15 or 20 miles per hour on any street, other than a state highway, adjacent to any school building or grounds, when children are going to or leaving the school, either at opening or closing hours, or during the noon recess period."

"(b) The legislative body of a city...may establish a 25-mile-per-hour prima facie limit in a school zone on portions of streets or highways, other than state highways, that are adjacent to school buildings or grounds and on which no school buildings or grounds are located, when the legislative body finds all of the following:

• (1) The portion of the street or highway is located within one-quarter of one mile of school buildings or grounds.
• (2) Schoolchildren must cross that portion of the street or highway when going to or leaving the school.
• (3) The portion of the street or highway does not have a sidewalk on both sides.

Key Factors Required in E&TS

An engineering and traffic survey shall include consideration of all of the following:

• Prevailing speeds of free-flowing traffic
• Collision records (at least 12 months)
• Highway, traffic, and roadside conditions not readily apparent
• Residential density and pedestrian activity
• Any other relevant factors (schoolchildren crossing, sight distance, etc.)

Key Requirements

Part 7 of the California Manual on Uniform Traffic Control Devices establishes:

• School Speed Limit signs (S4-1, S5-1) placement and specifications
• School warning signs (S1-1) and advance placement distances
• School crossing assemblies (beacons, signals, markings)
• "When Children Are Present" supplemental plaques
• Conditions for reduced speed zone activation

Key Guidance

This manual establishes:

• Standardized E&TS methodology across all California jurisdictions
• Data collection requirements (speed studies, collision analysis, site observations)
• Documentation standards for supporting ordinances and resolutions
• Special considerations for school zones and pedestrian-heavy areas

Parent-collected evidence (near misses, observations, crossing patterns) can inform these required factors.

Key Reforms

AB 43 amended CVC §627 and related sections to:

• Allow cities to consider multimodal travel and vulnerable road users in E&TS
• Clarify that speed limits need not be based solely on 85th percentile speeds
• Strengthen local authority to prioritize safety over vehicle speed
• Support Vision Zero and safe streets initiatives