Buffalo Bayou rises at the juncture of Willow Fork and Cane Branch west of Katy near the Waller county line in extreme northern Fort Bend County (at 29°46' N, 95°50' W) and flows sixty-five miles east, across southern Harris County, to its mouth on the San Jacinto River, at Lynchburg (at 29°46' N, 95°05' W). The stream is tidal from its junction with Whiteoak Bayou at Houston, eighteen miles above its mouth, and has been widened and deepened to form the Turning Basin and the Houston Ship Channel. Barker Dam, owned by the city of Barker and constructed by the United States Army Corps of Engineers in 1945, impounds Buffalo Bayou to form Barker Reservoir near Addicks. The lake serves primarily as a means of flood control and has a capacity of 135,800 acre-feet. In the 1990s Buffalo Bayou was extremely polluted. It flows from flat terrain with local shallow depressions surfaced by clay loam and sandy loam that support water-tolerant hardwoods, conifers, and grasses into the Houston metropolitan area and the industrial sector surrounding the Houston Ship Channel.