Colusa County, CA Landscaping Rules: Water Restrictions (2026)

010: new construction or rehabilitated landscapes of 2,500 square feet or more needing a building permit, plan check or zoning permit, across the urban residential (R-1 to R-4), commercial (C-1, C-2, C-H, C-R, MU), industrial (M-1, M-2, RD) and recreational (G-R) zones. Subsection A backs the schedule with hardware requirements: water-efficient irrigation systems such as bubbler, drip or mini-spray heads are required, along with check valves to prevent low-head drainage, nozzles sized to prevent overspray, and automatic, self-adjusting controllers with moisture or rain-sensor shutoff, all designed so water doesn't run onto adjacent property, hardscape, roadways or structures.

Subsection C requires each hydrozone to group plants with similar water needs. 080 layers the state's Model Water Efficient Landscaping Ordinance on top for any project also covered by the California Water Conservation in Landscaping Act, Government Code Section 65591 et seq. Compliance is verified when the Department of Planning and Building reviews the landscape plan, and the review authority for the permit, whether the Zoning Administrator or Planning Commission, must sign off before the irrigation system is installed.