The West Sacramento levee system is a portion of the Sacramento River Flood Control Project, a large scale levee project. The West Sacramento levee system is comprised of levees authorized by congress and a non-federal levee, levee which was locally constructed and is locally operated and maintained. The map of the levee system shows the leveed area, the area which would be prone to flooding in the absence of a levee. The West Sacramento levee system reduces the risk of flooding for a northern portion of the City of West Sacramento and adjacent agricultural lands from flood waters in the Sacramento River, Deep Water Ship Channel, and the Yolo Bypass. In addition to the urban population within the leveed area, a significant number of structures, with property values estimated in the billions of dollars, are present within the leveed area. Highway 50 and Interstate 80 cross through the leveed area. The West Sacramento levee system is constructed of a combination of earthen embankments, floodwalls, and four closure structures and which they all require year-round maintenance. The closure structures are closable openings in the levee, which when closed prevent flood flows from entering the leveed area. The Central Valley Flood Protection Board is the non-federal sponsor of the congressionally authorized portion and RD 900 sponsors the non-federal portion and both are the responsible agencies for operation and maintenance of the levee system.