The Whitewater River run from Timothy Lake Dam to Slackwater of Harriet Lake is a popular destination for kayakers and rafters in Oregon. The ideal streamflow range for this run is between 350 and 800 cubic feet per second (cfs). This flow rate allows for the rapids to be challenging yet navigable.

The class rating for this run is Class III, with some sections approaching Class IV. The run covers a distance of approximately 7 miles and features several significant rapids and obstacles. Notable rapids include the Toilet Bowl, which requires precise navigation to avoid being caught in a whirlpool, and the Pinball Rapid, which features several large boulders that create challenging whitewater.

There are specific regulations in place for this area. All boaters are required to obtain a permit from the Forest Service before entering the river. Motorized boats are not allowed on this section of the river, and all boaters must wear a personal flotation device at all times.

Overall, the Whitewater River run from Timothy Lake Dam to Slackwater of Harriet Lake is a challenging and exciting destination for experienced whitewater paddlers. It is essential to check the current streamflow and weather conditions before heading out, as water levels can change rapidly.