The Clear Creek watershed is located in southern Harris County. The watershed encompasses portions of Harris, Galveston, Brazoria, and Fort Bend counties; 16 cities including Houston, Brookside Village, Pearland, Friendswood, League City, Pasadena, the Clear Lake Area communities, and five drainage/flood control districts.
Clear Creek flows from west to east through Clear Lake and into Galveston Bay. Armand Bayou is the largest tributary to Clear Creek, and its drainage area is considered a separate watershed. The Clear Creek watershed covers approximately 197 square miles and includes two primary streams: Clear Creek and Turkey Creek. There are about 154 miles of open streams within the watershed, including the primary streams and tributary channels. Based on the 2010 U.S. Census, the estimated population of the Harris County portion of the Clear Creek watershed is 164,172.