Novato, CA Environmental Rules: Flood Zones (2026)

The F overlay is combined with a primary zoning district on the Zoning Map. Its stated intent is to protect people and property from flood hazard risks by regulating development and land uses. A suffix on the F symbol tells you which tier applies, and any land use normally allowed in the primary district can proceed unless the tier limits it.

F1 covers lands within a primary floodway, including water channels and adjacent flood plains. Allowable land uses are limited to boat docks, with Use Permit approval. F2 covers a secondary floodway, the portion between the F1 limits and where flood inundation can occur at low depths and velocities. Levees, dikes or filling can be allowed only where the Review Authority determines the activity is necessary to permit development and will not reduce the ponding capacity of the affected area. An exception can apply to a specified encroachment area or percentage of each parcel's ponding capacity, with the rest held as a ponding area. Before work starts, the landowner, the City, the Marin County Flood Control District and the Water Conservation District must sign an agreement. Lands in any F1 district on the property are dedicated to the City of Novato, the Marin County Flood Control District and the Water Conservation District, the landowner builds drainage improvements, and a performance bond can be required. Full use of undesignated F2 land requires the ultimate flood control channel improvements through the parcel and downstream to the mouth of the primary floodway.

F3 covers land within a 100-year flood plain, and all uses of the primary district are allowed. Where structures, fences, levees, dikes or filling can increase flood depth or velocity on adjacent land, an engineering and hydraulic study is required and development proceeds only in compliance with Chapter 5 of the Municipal Code. A proposed use must not increase the existing risk of flood damage on other lands, and conditions of approval can require structural measures and financial guarantees. The City can allow development that raises flood depths or velocities only after approving a flood protection plan and a written agreement with affected owners.

Two other chapters tighten F3 sites. All fences and walls in the F3 overlay require a Building Permit under Section 19.20.040.A.2. The grading exemption in Section 19.20.050 for movements under 200 cubic yards does not apply in the F-3 Overlay District.