Terwilliger Falls is one of the few waterfalls in the Northwest that both drops directly into a lake and can be viewed easily from the road. The creek plunges about 100 feet into Cougar Reservoir when the lake is at full pool, but when it's drawn down in the winter, the falls plunge into a small alcove - increasing to about 150 feet in height, and gaining a lower tier of about 20 feet more. Oddly, this is one of the only waterfalls I know of that gets taller when the creek is running higher (because the lake is usually drawn down when the creek is flowing hardest). The falls are prettiest when the lake is at full pool, but the increased height is also enough of a reason to visit the falls both in the summer and late winter.
- Terwilliger Falls is the Proposed name of this waterfall.
- Known Alternate Names: Rider Creek Falls
This waterfall doesn't appear to have any official name, but Terwilliger Falls has been used more frequently than anything else due to its proximity to the nearby Hot Springs. I had previously listed this entry as Rider Creek Falls, but it turns out there is a waterfall on the main stem of Rider Creek which is more deserving of the title.
Located along Cougar Reservoir, off Highway 126. Cougar Reservoir is accessed from the northern end of the Aufderheide Memorial Parkway, located about 4 Â½ miles east of Blue River, or 5 miles west of McKenzie Bridge along Highway 126. Follow the Aufderheide (FR 19), also signed for Cougar Reservoir and Terwilliger Hot Springs, for half a mile, and bear left at the first major intersection - following signs for the Hot Springs and Oakridge. In another 3 miles, you'll pass the Cougar Dam, and 4 Â¼ miles further, you'll reach the falls, with the parking area for Terwilliger Hot Springs immediately beyond on the left - a total of 7.6 miles from Highway 126. Park and walk back along the lagoon to view the falls. There is a day use fee for visiting the springs, but viewing the falls is open to all.