The Whitewater River Run from Long Gulch to Boise National Forest Boundary in Idaho is a thrilling adventure that features several rapids and obstacles. The ideal streamflow range for this run is between 700 and 3000 cfs, which is dependent on the season and rainfall. The segment mileage for this run is approximately 21 miles, featuring class III and IV rapids.

One of the significant rapids on this run is the Staircase, which is a series of drops and pools that require precise maneuvering. The Pearly Gates is another challenging rapid on this run that requires proper scouting and skillful navigation. Other notable rapids on this run include the Ledges, Smokey Falls, and Devil's Slide.

There are specific regulations that must be adhered to when running this river. For instance, all boaters must wear a personal flotation device at all times, and all equipment must be in good working condition. Additionally, motorized boats are not permitted on this run, and all boaters must follow Leave No Trace principles to protect the environment.

In conclusion, the Whitewater River Run from Long Gulch to Boise National Forest Boundary in Idaho is a thrilling run that requires skillful navigation. The ideal streamflow range is between 700 and 3000 cfs, with class III and IV rapids. Boaters must adhere to specific regulations and follow Leave No Trace principles to protect the environment.