Buying Land in Colusa County, CA: Water-Allocation Risk & Williamson Act Farmland

Colusa County's rice economy depends on reliable irrigation water — and that reliability has genuinely broken down in recent drought years.

Colusa County is one of California's original 27 counties and remains overwhelmingly rural and agricultural — it's the Sacramento Valley's top rice-producing county, growing more than 150,000 acres of rice in a normal year. Water-allocation volatility and Williamson Act farmland status, rather than any urban land-use issue, are the defining facts a buyer evaluating agricultural land here should understand.

What’s the transfer tax in Colusa County?

Colusa County's documentary transfer tax is flat across the entire county at $1.10 per $1,000 of consideration, with no city — including Colusa or Williams — imposing an additional surcharge on top.

Both incorporated cities sit at the same combined $1.10/$1,000 total — the standard $0.55 county + $0.55 city split, not an add-on. On a $350,000 sale, that's $385 in transfer tax anywhere in the county.

How real is the water-allocation risk for agricultural land here?

It's a genuine, recent economic shock, not a generic drought caveat. In 2022, water allocations to Sacramento Valley rice growers dropped to roughly 0.4 acre-feet per acre, forcing the fallowing of about 370,000 of 450,000 normally-farmed acres — concentrated in Colusa and Glenn counties — with direct financial losses estimated above $270 million.

If you're buying agricultural or water-rights-dependent land in Colusa County, water-allocation history and current irrigation-district status is a materially important, county-specific due-diligence item.

What is Williamson Act land, and does it affect Colusa County properties?

It can — Colusa County, like other Sacramento Valley rice counties, carries significant acreage under Williamson Act agricultural preserve contracts.

A landowner voluntarily restricts a qualifying parcel (preserves generally run at least 100 acres) to agricultural or open-space use in exchange for property tax assessed on agricultural-use value rather than market value. The contract auto-renews annually on a rolling term (minimum 10 years) unless either party files a formal notice of non-renewal, and it runs with the land rather than ending at sale — pulling land out early triggers cancellation fees, and a non-renewal otherwise starts a multi-year wind-down before the restriction lifts. Confirm Williamson Act contract status on any rural or agricultural Colusa County parcel with the county Assessor's office before assuming it can be freely rezoned or developed.

What should I expect outside the towns of Colusa and Williams?

Very low population density even by rural-Sacramento-Valley standards. Most residential property outside Colusa and Williams relies on private well water and septic systems.

Factor in longer response times for specialty trades, as is typical in other sparsely populated Sacramento Valley counties.

Disclosure landscape

Water-allocation history and irrigation-district status should be confirmed for any agricultural or water-rights-dependent parcel — 2022 saw major fallowing and financial losses regionally.
Confirm Williamson Act contract status on rural or agricultural parcels with the county Assessor's office before assuming unrestricted development rights.
No local transfer-tax add-on applies in Colusa or Williams — the flat countywide $1.10/$1,000 rate applies everywhere.

Frequently asked

Why does water allocation matter so much for buying land in Colusa County?

Because it's not hypothetical — in 2022, reduced water allocations forced the fallowing of roughly 370,000 of 450,000 normally-farmed acres across Colusa and Glenn counties, with over $270 million in direct losses. Check a specific parcel's water-rights and irrigation-district status and its recent allocation history before buying agricultural land.

What happens if I buy Williamson Act farmland in Colusa County and want to develop it?

You'll need to address the contract first — pulling land out early means cancellation fees, and without an early cancellation there's a multi-year non-renewal wind-down before the agricultural-use restriction fully lifts. Confirm status with the county Assessor before assuming a rural parcel is unrestricted.

Is there a city transfer tax add-on in Colusa or Williams?

No. Both cities sit at the same flat $1.10 per $1,000 combined rate — no city-level surcharge anywhere in the county.

Sources

This is educational guidance, not legal advice. Consult a California real estate attorney for legal questions specific to your transaction.