Tryon Creek Watershed
The Tryon Creek watershed spans approximately 4,200 acres across two cities, including 3,300 acres in Southwest Portland and 900 acres in Lake Oswego. About a fifth of the watershed is in protected greenspaces and natural areas, including 650 acres of the lower watershed in Tryon Creek State Natural Area. The other eighty percent is urban, with houses, roads, schools and office buildings offering people places to work and live.
Tryon Creek is a seven-mile creek that originates in the West Hills of Portland and flows southeast through Multnomah Village to Tryon Creek State Natural Area, ending at its confluence with the Willamette River. Its major tributaries include Arnold, Nettle, Falling, Quail and Park Creeks.
Everywhere is a watershed!
Often watersheds are urbanized near the output point and undisturbed or rural at the headwaters. Tryon Creek is the opposite!
The Tryon Creek watershed is urbanized in the headwaters (Multnomah Village, I-5 corridor) and has its largest natural area close to its output point.
Fish and Wildlife
Tryon Creek’s many streams, open spaces and forested land support a variety of plants and wildlife. Coyotes, deer, foxes, beaver and other large mammals live in parks and back yards, relying on interconnected greenways for food and shelter. Steelhead trout migrate to the upper reaches of Tryon Creek from the ocean. Birds count on our watershed’s streams and wooded slopes for shelter during migration, or live with us year-round. Recently, listed Coastal Coho and Willamette Spring Chinook juveniles have been located in Tryon Creek.
The US Fish & Wildlife Service recently published a paper,”An urban stream can support a healthy population of coastal cutthroat trout” in Urban Ecosystems. They found the characteristics of Coastal Cutthroat Trout in Tryon Creek were similar to populations not influenced by urbanization. Their results suggest that Tryon Creek can serve as an example of a healthy fish population in an urban watershed.