Aliso Creek is a small river in Orange County, California, in the United States. From its source in the Santa Ana Mountains to its mouth at the Pacific Ocean, it is about long. Its watershed is about 30.4 square miles (79 square kilometers) in size. The name comes from the Spanish word "aliso", meaning alder. Six tributaries join it along its length, which are Wood Canyon Creek, Sulphur Creek, the Dairy Fork, Aliso Hills Channel, Munger Creek and English Canyon.