Tualatin River Basin map

Detailed Description
The area bounded by black lines is the Tualatin River Basin. Red triangles signify USGS water-quality monitors. The Tualatin River has several major tributaries, including Scoggins Creek, Gales Creek, Dairy Creek (with its East Fork, West Fork, and McKay Creek branches), Rock Creek (including Beaverton Creek), and Fanno Creek. In addition to these, there are numerous smaller tributaries throughout the Tualatin River basin
Sources/Usage
Public Domain.