Off-grid site report
Colusa County, CA
39.2141, -122.0092 · 69 ft elevationRead this before you act on anything below. This is my researched starting point for Colusa County, CA, not legal advice and not a guarantee. Rules change, and the deciding facts on any specific parcel (setbacks, perc results, overlay districts, deed restrictions, road frontage) live at the county or town office, not in any database. Before you buy land or build, confirm the current rules directly with the local zoning and health offices - the sources on this page tell you exactly who to call.
The local rulesColusa County, CA
Zoning & raw-land occupancy
Varies locallyColusa County has a countywide Zoning Code (adopted 2014) administered by Community Development, but allowed uses vary by parcel designation. The county advises calling Planning staff with your parcel's address and APN before any occupancy or development plans. source
Dwellings, tiny homes & RVs
Unclear - verifyNo official county page specifically addresses tiny homes or long-term RV occupancy; Building Division applies standard state dwelling classifications. Specifics are not confirmed, call the Building Division. source
Building permits & codes
RestrictedThe county Building Department reviews plans, inspects, and enforces code countywide, including state-required smoke/CO alarm rules whenever a permit is pulled for repair or alteration. source
Septic & composting toilets
RestrictedColusa County Environmental Health issues septic permits and has adopted its own OWTS standards stricter than the state baseline; fee categories exist for various system types but exact amounts should be confirmed with the office. Composting toilets are not addressed in official sources found. source
Greywater reuse
Generally allowedNo county-specific greywater ordinance was found; the statewide California Plumbing Code Chapter 15 framework appears to apply, administered through Environmental Health/Building review. source
Rainwater harvesting
Generally allowedNo Colusa County ordinance restricting rooftop rainwater harvesting was found; the state's Rainwater Capture Act framework appears to apply without a located county supplement.
Private wells & water rights
RestrictedEnvironmental Health/Water Resources permits and inspects private wells (48-hour driller notice required), and groundwater use is further constrained by SGMA in the county's two designated basins. source
Living disconnected from utilities
Unclear - verifyNo standalone ordinance on disconnecting from grid utilities was found; it's likely governed indirectly through septic, well, and building permitting. The county's emergency domestic well outage program suggests private-well reliance is common and monitored. source
Sun30-year normals
- Peak-sun hours, annual average
- 5.7 hrs/day
- Worst month (sizes an off-grid array)
- 3.3 hrs/day
- Yearly output per 1 kW of panels
- 1,563 kWh
JFMAMJJASOND
Weather1991-2020
- Precipitation
- 18 in/yr
- Heating degree days
- 2,589 (mild)
- Frost-free season
- Feb 13 to Dec 3
How far help isstraight-line
- Hospital
Orchard Hospital - 20.1 mi
- Fire station
Colusa Fire Department - 0.2 mi
- Hardware store
Messick Ace Hardware - 0.1 mi
- Grocery
Grocery Outlet - 8.1 mi
From OpenStreetMap. Road miles will be longer, often much longer in hill country.
Plan this spot
These open with this location's real numbers already filled in (ZIP 95932).
Size a solar systemHeat loss & insulationFirewood per winterRainwater harvestGarden sizePanel tilt
Looking at a specific parcel in Colusa County, CA?The rules above are the jurisdiction. The land check runs the parcel itself: flood zone, soils and septic suitability, wetlands, slope, access, climate, and these verdicts, from a parcel number or coordinates.
Check a parcel →Share or save this report:New report
Sources: US Census Bureau geocoder; NLR PVWatts v8 (solar); NOAA NCEI 1991-2020 climate normals (nearest station) or Open-Meteo (ZIP-centroid) for weather; Open-Elevation; OpenStreetMap contributors. Public data retrieved Aug 22, 2026; agencies update their layers on their own schedules. Planning data, not a survey or legal advice.
New here, or not sure where this fits? Start here walks through the whole thing in order.