Crab Creek is sometimes separated into Upper Crab Creek, which runs from the creek’s source to Potholes Reservoir, and Lower Crab Creek, which runs from Potholes Reservoir to the Columbia River. Sometimes the stream is divided into three parts—Upper Crab Creek, from its source to Brook Lake, Middle Crab Creek, from Brook Lake to and including Potholes Reservoir; and Lower Crab Creek, from below Potholes Reservoir to the Columbia River.