Pacific Crest HUC12

The Pacific Crest is far less defined than the Continental Divide and there are a handful of rivers that breach this divide making it an imperfect divide. These rivers include the Columbia River in Washington and Oregon, the Klamath River in Oregon, and the Pit and Feather Rivers in northern California. 8-digit HUC unit polygons cannot be used to map this boundary and the Pacific Crest trail itself doesn't follow the divide. Therefore, I used HUC12 units to define the Pacific Crest following topographic drainage divides and crossing as few major rivers as possible while still trying to maintain the general shape of the Cascade-Sierra spine.