Environmental Rules in Los Angeles County, CA (2026)

7 county-level rules, plus city-specific rules for 21 cities in Los Angeles County, California.

Verified from official government sources

Note: These county rules apply to unincorporated areas of Los Angeles County. If you live within an incorporated city, that city's own rules apply: see the city list below.

Stormwater Management

All grading in unincorporated LA County must comply with NPDES requirements: best management practices must be installed before grading begins and maintained until permanent drainage is in place, or daily fines up to $500 per day apply.

Environmental: Stormwater

Significant Restrictions

Los Angeles County Code § J110.8

J110.8 National Pollutant Discharge Elimination System (NPDES) compliance. J110.8.1 General. All grading plans and permits and the owner of any property on which such grading is performed shall comply with the provisions of this Section for NPDES compliance. All best management practices shall be installed before grading begins or as instructed in writing by the Building Official for unp...

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Erosion Control

All cut and fill slopes in unincorporated LA County must be planted and irrigated to prevent erosion, with taller slopes requiring both ground cover and shrubs or trees at specific spacing: planting must be established before the county grants final grading approval.

Environmental: Erosion Control

Significant Restrictions

Los Angeles County Code §§ J110.1, J110.3

J110.1 General. The faces of cut and fill slopes shall be prepared and maintained to control erosion. This control shall consist of effective planting, erosion control blankets, soil stabilizers, or other means as approved by the Building Official. J110.3 Planting. The surface of all cut slopes more than 5 feet (1.5 m) in height and fill slopes more than 3 feet (0.9 m) in height shall be...

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Coastal Development

Several unincorporated LA County areas fall within the California Coastal Zone, including communities near Malibu and the Santa Monica Mountains. Coastal development permits from the California Coastal Commission may be required. LA County DRP administers local coastal programs for unincorporated coastal areas.

LA County Coastal Development Rules

Some Restrictions

California Coastal Commission — Coastal Zone Boundary Maps (PRC Sec. 30103)

Public Resources Code (PRC) Section 30103(a) specifically defines California's Coastal Zone as that land and water area of the State of California from the Oregon border to the border of the Republic of Mexico depicted on maps identified and set forth in Section 17 of that chapter of the Statutes of the 1975-76 Regular Session enacting PRC Division 20 (the Coastal Act of 1976). PRC Section 3010...

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Flood Zones

Grading, excavation, and fill are prohibited in designated floodways in unincorporated LA County unless a California-licensed civil engineer certifies in a hydraulic analysis that the work will not raise the base flood level.

Environmental: Flood Zones

Heavy Restrictions

Los Angeles County Code § J101.2

J101.2 Flood hazard areas. Unless the applicant has submitted a hydrology and hydraulic analysis, prepared in accordance with standard engineering practice by a California licensed civil engineer, that demonstrates the proposed work will not result in any increase in the level of the base flood, grading, excavation and earthwork construction, including fills and embankments, shall not be per...

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Boat Dock Permits

In unincorporated Los Angeles County, marinas, docks, piers, and boat launches need a Conditional Use Permit in the Open Space (O-S) zone and are barred outright in the A-1, A-2, R-R, and Watershed zones.

LA County Boat Dock Zoning Permit

Significant Restrictions

Los Angeles County Code § 22.16.030, Table 22.16.030-B

TABLE 22.16.030-B ... CUP Conditional Use Permit Chapter 22.158 ... A-1 A-2 O-S R-R W ... Marinas, small boat harbors, docks, piers, boat launches, and similar recreational facilities - - CUP - -

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Defensible Space

Los Angeles County's defensible space rules require specific vegetation management within 100 feet of structures on or adjacent to brushland. Dead vegetation must be removed continuously, firewood stored 30 feet from structures, and named flammable species like eucalyptus and pampas grass must be cleared regardless of ornamental status.

Environmental: Defensible Space

Significant Restrictions

Los Angeles County Code Title 32 (Fire Code), §§ 325.2.1.1, 325.2.1.3, 325.2.1.5, and 325.2.1.6

§ 325.2.1.1 Ornamental plants and trees. Ornamental plants and trees known to be flammable — including but not limited to acacia, cedar, cypress, eucalyptus, juniper, pine, and pampas grass — shall not be exempt from compliance with these requirements. § 325.2.1.3 Dead vegetation. Remove all dead or dying grass, plants, shrubs, trees, branches, leaves, weeds, and pine needles. Maintain any tree...

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Flood Elevation Requirements

In the unincorporated Santa Monica Mountains Coastal Zone, new residential construction in FEMA A, AE, or AH flood zones must have its lowest floor built at least one foot above the base flood elevation.

Los Angeles County Coastal Flood Elevation Rule

Some Restrictions

Los Angeles County Code Section 22.44.2102(I)(4)

For residential structures in Zones A, AE, or AH on a FIRM, the lowest floor (including basement) shall be elevated at least one (1) foot above the base flood elevation, where base flood shall mean a flood having a one percent chance of being equaled or exceeded in every year (a 100-year flood).

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