Restoring Seattle and Shoreline's largest watershed (web site under construction)
The Thornton Creek watershed covers roughly 11.6 square miles in northeast Seattle and Shoreline. Over 90% of the creek’s main channel, more than 15 miles, flows above ground through more than 700 backyards and through 15 parks and natural areas.
It is both Seattle’s and Shoreline’s largest watershed, and drains into Lake Washington at Matthews Beach Park. That water ultimately goes through the Lake Washington Ship Canal to Puget Sound. The creek is a historic home to at least five species of Pacific salmon and trout.
Click map to enlarge.
Thornton Creek Alliance (TCA) is an all-volunteer grassroots, nonprofit organization dedicated to preserving and restoring an ecological balance throughout the Thornton Creek watershed. Our goal is to benefit the watershed by encouraging individuals, groups, schools, businesses, and government to work together in addressing the environmental restoration of the creek system including: water quality, stabilization of water flow, flood prevention, and habitat improvement through education, collaboration, and community involvement.