The Bull Run River is a scenic waterway in northwestern Oregon, originating in the Bull Run Watershed of the Mount Hood National Forest. It flows generally westward for approximately 21 miles before joining the Sandy River near the town of Bull Run. The river and its tributaries drain a watershed of about 140 square miles.

For paddlers, the Bull Run offers several notable whitewater sections. The most popular run is the 1.75-mile stretch from Bull Run Power House to the confluence with the Sandy River at Dodge Park. This Class III section features one significant rapid, Bull Run Rapid, about 0.8 miles from the put-in. Above this, the Upper Bull Run section provides a beautiful, intimate canyon run with technical Class III rapids at normal flows. The overall difficulty ranges from Class II to III, making it suitable for intermediate paddlers with solid whitewater skills. However, the river can become more challenging at high water levels, requiring advanced skills and experience.

The Bull Run is typically paddled in spring and early summer when snowmelt and rainfall provide adequate flows. Fall rains can also create good paddling conditions. Paddlers should check flow levels at the Bull Run gauge, with 1200-3000 CFS considered a good range for the lower section.

The river corridor supports diverse flora and fauna typical of the western Cascades, including Douglas fir, western red cedar, and various wildlife species. The watershed's protected status helps maintain its pristine condition. Key landmarks include the Bull Run Power House at the put-in and the scenic canyon sections. The take-out at Dodge Park marks the confluence with the Sandy River, offering paddlers the option to continue downstream on the Sandy for a longer trip.

Access is relatively straightforward, with the main put-in near the Bull Run Power House and the take-out at Dodge Park. The nearby city of Gresham, about 12 miles west, serves as a convenient base for paddlers.

Historically, the Bull Run River has been crucial to Portland's water supply since the late 19th century. The watershed remains highly protected to maintain water quality, with limited public access in many areas.

Safety considerations include potential wood hazards and cold water temperatures. Paddlers should be aware of flow-dependent challenges and always wear appropriate safety gear. Some sections may have access restrictions due to the watershed's protected status, so checking current regulations is essential. While primarily used for day trips, paddlers can combine the Bull Run with sections of the Sandy River for longer adventures, potentially extending to Oxbow Park for a multi-day experience.