Buffalo Bayou is a slow moving body of water which flows through Houston in Harris County, Texas. Formed 18,000 years ago, it has its source in the prairie surrounding Katy, Fort Bend County, and flows approximately east through the Houston Ship Channel into Galveston Bay and the Gulf of Mexico. In addition to drainage water impounded and released by the Addicks and Barker reservoirs, the bayou is fed by natural springs, surface runoff, and several significant tributary bayous, including White Oak Bayou, Greens Bayou, and Brays Bayou. Additionally, Buffalo Bayou is considered a tidal river downstream of a point west of the Shepherd Drive bridge in west-central Houston.