The Sierra Madre Mountains form the watershed's boundary to the north, while the San Rafael Mountains form the southern boundary. The first half of the river, in the Los Padres National Forest, specifically the San Rafael Wilderness, travels roughly northwest. Outside of the National Forest, the river flows roughly west to its confluence with the Cuyama River, about 20 miles upstream from the Pacific Ocean. The river is completely free flowing and does not have any diversions. Its sole dam is a 3-meter dam on Horse Canyon, one of its tributaries, but it is filled with sediment and causes little restriction to the river's overall flow. It is designated as a wild and scenic river in the National Wild and Scenic Rivers System.