Thornton Creek Alliance (TCA) is an all-volunteer organization whose 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.  It has been twenty years since a few concerned activists began organizing to improve water quality, flood prevention, and habitat throughout the northeast Seattle watershed which includes the North and South Branches of Thornton Creek.

In the fifty years between 1940 to 1990, the population of northeast Seattle quadrupled from about 17,500 to 70,000.  Population increase led to more and more houses, roads, and commercial developments being squeezed in, without regard for the drainage basin which flows out into Lake Washington at Matthews Beach (about NE 93^rd Street.)  The result was degradation of the water, and flooding of roads and houses, especially at the Confluence of the two branches of Thornton Creek.

In 1994 the TCA was formed and began advocating for pollutant control regulations, preservation of green spaces and creek environment which would help prevent periodic flooding.

Everyone is invited to come out for the Twentieth Anniversary Celebration of the Thornton Creek Alliance on Sunday, September 14, 2014 from 1 to 4 PM at Cromwell Park, 18030 Meridian Ave North in Shoreline.  There will be live music, ice cream and cake, childrens activities and displays about current creek restoration efforts.