Colusa is the county seat of Colusa County, California. The population was 5,971 at the 2010 census, up from 5,402 at the 2000 census. Colusi originates from the local Coru Indian tribe, who in the 1840s lived on the opposite side of the Sacramento River.GeographyAccording to the United States Census Bureau, the city has a total area of 1.8sqmi, all of it land. According to the United States Geological Survey, the city's location is at.Colusa is on the Sacramento River, which has a high levee so that the river is not clearly apparent from the city.Colusa features a historic Chinatown, Carnegie Library building constructed in 1905, and an architecturally noteworthy courthouse built in a classical style, among its historically notable buildings.ClimateAccording to the Köppen Climate Classification system, Colusa has a warm-summer Mediterranean climate, abbreviated "Csa" on climate maps.Climate EventsDuring December 1996 - January 1997, the nearby Colusa Weir Gage reached flood stage. This historic flooding event devastated the region by destroying thousands of crop acres (rice, tomatoes, alfalfa) and property. The Colusa Weir Gage reached flood stage 68.67 feet on 1/3/1997.
