Agency Creek enters Simcoe Creek at river mile 9.5, and drains a 23-square-mile watershed. Middle Columbia River steelhead use the creek for spawning and rearing. Steelhead redd counts in Agency Creek have ranged from 4 to 20 since 1999, and the creek is recognized as a spawning aggregation for steelhead recovery purposes. Juvenile steelhead rear through the summer in the creek near its confluence with Simcoe Creek.
This project was implemented to assist in managing the migration of cattle from low elevations in the spring to higher elevations in the early summer. Prior to the project, upon cattle turnout on May 1, cattle would quickly travel approximately 25 miles to the headwater meadows of Satus and Toppenish Creeks. Livestock immediately impacted several important high elevation meadows, by overgrazing and by creating hardened cattle trails. These impacts further increased channel incision and bank erosion in these areas..
Lincoln Meadows is a headwaters meadow for Toppenish Creek. Headwater meadows are important because they contain culturally important first foods and function as water storage to maintain summer base flows in streams, which supports aquatic life. Lincoln Meadows has been impacted by a variety of human related activities, such as roads and cattle grazing, that have severely degraded the meadow's capabilities.