Crab Creek turns southward after Brook Lake. The CBP's East Low Canal, one of the projects main irrigation canals, crosses but does not mix waters with Crab Creek. At the city of Moses Lake Crab Creek empties into the Parker Horn arm of Moses Lake. Just before reaching the lake Crab Creek receives the waters of Rocky Coulee Wasteway, a mix of the intermittent Rocky Coulee Creek and irrigation runoff from the East Low Canal. Before the CBP there was no perennial flow between Brook Lake and Moses Lake. Only during periods of high water did Crab Creek flow through this area.