The District has eight zones. They address specific flooding problems within certain watersheds.
- Zone 1: Novato
- Zone 3: Richardson Bay
- Zone 4: Bel Aire
- Zone 5: Stinson Beach
- Zone 6: San Rafael Meadows
- Zone 7: Santa Venetia
- Zone 9: Ross Valley
- Zone 10: Inverness
There were studies to form Zones 2 and 8 in the past, but no recommendation to create a new zone so they are not included in the District's workplan.
The Flood Zones do not cover the entire county and are mostly concentrated in the county’s eastern urbanized corridor. The majority of the county’s land is not contained within a designated zone.
Within the zones, the District performs construction, operation, and maintenance of:
- Pumps and Pumping stations
- Creeks and Drainage Ways
- Flow and Tide Gates
- Drainage Pipes
- Stormwater detention basins
All major actions by the Zones require authorization by the Board of Supervisors of the Flood Control District.
Each zone has an Advisory Board of five or seven residents. They are are appointed by the District Board of Supervisors.
The advisory boards:
- Review Zone budgets
- Review project plans and budgets
- Advise the Board of Supervisors on zone-related matters