Southern California Work-Zone Authority
Across Southern California the same work can follow different requirements depending on who owns the road. This page explains which agency governs which right-of-way — and where to verify permits, standards, and conditions.
Last reviewed: June 24, 2026
Applies to: the public right-of-way in Los Angeles, Orange, Riverside, San Bernardino, San Diego, Ventura, and Imperial counties.
Why Jurisdiction Decides the Rules
In Southern California, the requirements for a work zone depend on who owns and maintains the road. Identifying the road owner is the first step to knowing which permit and which standards apply.
- State highways and freeways are governed by Caltrans, through the district that covers the area.
- County-maintained roads(generally in unincorporated areas) are governed by the county's public works or transportation agency.
- City streets and sidewalksare governed by the city's public works or engineering department.
Standards That Apply Statewide
Regardless of which agency owns the road, temporary traffic control in California follows the California MUTCD. Caltrans standard plans and specifications, Cal/OSHA worker-safety requirements, and ADA accessibility requirements also apply, and local agencies add their own standard plans and permit conditions.
Where several requirements apply at once, they do not cancel each other out — the most specific and most protective requirement generally governs, as reconciled in the approved plan and permit.
Caltrans Districts in Southern California
For work on the state highway system, the governing Caltrans district depends on the county:
| Caltrans District | Counties |
|---|---|
| District 7 | Los Angeles, Ventura |
| District 8 | Riverside, San Bernardino |
| District 11 | San Diego, Imperial |
| District 12 | Orange |
Southern California Counties
For county-maintained roads, work is generally authorized through an encroachment permit issued by the county road agency. The specific permit types, hours, notice, fees, and conditions vary by county and must be verified with that agency.
| County | County road agency | Caltrans district (state highways) |
|---|---|---|
| Los Angeles | Los Angeles County Public Works | District 7 |
| Orange | OC Public Works | District 12 |
| Riverside | Riverside County Transportation Department | District 8 |
| San Bernardino | San Bernardino County Public Works | District 8 |
| San Diego | County of San Diego Department of Public Works | District 11 |
| Ventura | Ventura County Public Works Agency | District 7 |
| Imperial | Imperial County Public Works | District 11 |
Cities
Each incorporated city generally issues its own permits — often an encroachment permit — for work in city streets and sidewalks, through its public works or engineering department. Requirements, allowable hours, notice periods, and fees vary from city to city and must be verified with the specific city.
Official Sources
- California MUTCD (Caltrans) — the state standard for traffic control devices.
- Caltrans (dot.ca.gov) — state highway standards, districts, and encroachment permits.
For county and city requirements, use the road agency named above and confirm current permit types, conditions, hours, and notice directly with that agency.