The Cypress Creek watershed is located in northwest Harris County and extends into Waller County. Rainfall within the 267 square miles of the Cypress Creek watershed drains to the watershed’s primary waterway, Cypress Creek (K100-00-00). There are 250 miles of open waterways in the Cypress Creek watershed, including Cypress Creek and its major tributaries, such as Little Cypress Creek (L100-00-00), Turkey Creek (K111-00-00), Dry Gully (K133-00-00), and Mound Creek (K166-00-00).
Based on the 2010 U.S. Census, the estimated population of the Harris County portion of the Cypress Creek watershed is 347,334.The western portion of the watershed is historically rural farmland, while the eastern and central portions have developed rapidly in the past 20 to 30 years. The Cypress Creek watershed has a diverse environment with animal species ranging from the American alligator to the bald eagle. The watershed upstream of Highway 290 is part of the well-known Katy Prairie ecosystem.