San Diego River
|San Diego River|
Looking upstream near mouth
|Region||San Diego County|
|- location||5 miles (8 km) northwest of Julian, California|
|- elevation||750 ft (229 m)|
|- location||Community of Ocean Beach, San Diego, California|
|- elevation||13 ft (4 m) |
|Length||52 mi (84 km)|
|Basin||420 sq mi (1,088 km2) |
|- average||38.3 cu ft/s (1 m3/s)|
|- max||94,500 cu ft/s (2,676 m3/s)|
|- min||0 cu ft/s (0 m3/s)|
The San Diego River is a river in San Diego County, California. It originates in the Cuyamaca Mountains northwest of the town of Julian, then flows to the southwest until it reaches the El Capitan Reservoir, the largest reservoir in the river's watershed at 112,800 acre feet (139,100,000 m3). Below El Capitan Dam, the river runs west through the cities of Santee and San Diego. While passing through Tierrasanta it goes through Mission Trails Regional Park, one of the largest urban parks in America. The river discharges into the Pacific Ocean near the entrance to Mission Bay, forming an estuary.
The river has changed its course several times in recorded history. When the first European settlers arrived in the late 18th century it emptied into False Bay, the present day Mission Bay. At some point in the 1820s it altered course and began to empty into San Diego Bay, which continued for nearly 50 years. Because of fears that the harbor would silt up, the river was diverted to its present course in 1877 by a dam and the straightening of the channel to the ocean.
The river travels 52 miles (84 km) from its headwaters to the ocean. The river's tributaries include Boulder Creek, Cedar Creek, Chocolate Creek, Coleman Creek, Conejos Creek, Forester Creek, Los Coches Creek and San Vicente Creek.
Four additional reservoirs lie in the river's watershed. Cuyamaca Reservoir is located on Boulder Creek and San Vicente Reservoir is fed by San Vicente Creek. Lake Jennings and Lake Murray are formed by the damming of canyons.
The San Diego River Conservancy was established by an act of the California Legislature to preserve, restore and enhance the San Diego River area. The Conservancy is a non-regulatory agency of the state government with an independent nine-member governing board. It is tasked to acquire, manage and conserve land and to protect or provide recreational opportunities, open space, wildlife species and habitat, wetlands, water quality, natural flood conveyance, historical/cultural resources, and educational opportunities. One important goal is to help create a river-long park and hiking trail, stretching the full length of the river from its headwaters in the Cuyamaca Mountains to the Pacific Ocean.
From mouth to source:
San Diego 
- U.S. Geological Survey Geographic Names Information System: San Diego River
- "Boundary Descriptions and Names of Regions, Subregions, Accounting Units and Cataloging Units". U.S. Geological Survey. Retrieved 2010-08-22.
- Smythe, William, "History of San Diego, 1542-1908", Part 7, Chapter 2
- San Diego River Park Foundation website
- San Diego River Conservancy website