The White Rock Creek Tributary is a small river located in Northern California. The ideal streamflow range for this river run is between 150-400 cfs, with 300 cfs being the optimal flow for kayakers and rafters. The river is rated as Class III, with a few Class IV rapids thrown in for good measure. The segment mileage for the White Rock Creek Tributary is approximately 9 miles.

Some of the specific rapids and obstacles on this river include "The Meatgrinder," "Pinball," and "The S-Turns." These rapids are known for their technical challenges, with steep drops, tight turns, and turbulent water.

In terms of regulations, the White Rock Creek Tributary is located on private property, which means that river runners must obtain permission from the landowner before accessing the river. Additionally, visitors are required to pack out all trash and leave the area in the same condition as they found it.

Overall, the White Rock Creek Tributary is a challenging and exciting river run that is best suited for experienced kayakers and rafters who are looking for a technical challenge. With its steep drops, tight turns, and turbulent water, this river provides a thrilling adventure for those who are up to the challenge.