The Otay River () is a

river A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of wate ...

in southern

San Diego County, California San Diego County (), officially the County of San Diego, is a county in the southwestern corner of the U.S. state of California. As of the 2020 census, the population was 3,298,634, making it California's second-most populous county and the fi ...

. The river begins at

San Miguel Mountain San Miguel Mountain is a mountain located in Chula Vista, California. It is 2,567' high, and is the 84th highest peak in San Diego County San Diego County (), officially the County of San Diego, is a county in the southwestern corner of the ...

, flows through the Upper and Lower Otay Reservoirs, and continues on between the southern part of the

Chula Vista Chula Vista (; ) is the second-largest city in the San Diego metropolitan area, the seventh largest city in Southern California, the fifteenth largest city in the state of California, and the 78th-largest city in the United States. The popul ...

and the Otay Mesa West district of

San Diego San Diego ( , ; ) is a city on the Pacific Ocean coast of Southern California located immediately adjacent to the Mexico–United States border. With a 2020 population of 1,386,932, it is the List of United States cities by population, eigh ...

, to its

river mouth A river mouth is where a river flows into a larger body of water, such as another river, a lake/reservoir, a bay/gulf, a sea, or an ocean. At the river mouth, sediments are often deposited due to the slowing of the current reducing the carrying ...

San Diego Bay San Diego Bay is a natural harbor and deepwater port located in San Diego County, California near the U.S.–Mexico border. The bay, which is long and wide, is the third largest of the three large, protected natural bays on California's of c ...

River

The river has a watershed. To its north is the watershed of Sweetwater River, and to its south is the watershed of

Tijuana River , name_etymology = , image = Presa Tij 1.jpg , image_size = , image_caption = Dam on the Tijuana River in Mexico. , map = Tijuana River Basin.svg , map_size = 250 , map_caption ...

. Between

Interstate 5 Interstate 5 (I-5) is the main north–south Interstate Highway on the West Coast of the United States, running largely parallel to the Pacific coast of the contiguous U.S. from Mexico to Canada. It travels through the states of Califor ...

and

Interstate 805 Interstate 805 (I-805) is a major north–south auxiliary Interstate Highway in Southern California. It is a bypass auxiliary route of I-5, running roughly through the center of the Greater San Diego region from San Ysidro (part of the c ...

Otay Valley Regional Park Otay may refer to: Locations * Otay Centenario * Otay Mesa, San Diego * Otay Mesa Port of Entry * Otay Mesa West, San Diego * Otay Ranch High School * Otay Ranch Town Center *Otay River *Lower Otay Reservoir *Rancho Otay Rancho Otay was a Mexican ...

. , there is a plan to restore part of its pre- Mexican era estuary on lands utilized by the

South Bay Salt Works The South Bay Salt Works is a salt factory in southern San Diego, near Chula Vista, in the South Bay region of San Diego County, California. Initially operating under the name La Punta Salt Works operations dating back to at least 1871, for a ...

Otay Reservoirs

Savage Dam Savage Dam is a dam across the Otay River in the San Ysidro Mountains of southwestern San Diego County, California. It is a concrete arch gravity structure high, and serves to store water from the San Diego Aqueduct's third pipeline for backup m ...

, completed in 1921, forms the

Lower Otay Reservoir Lower Otay Reservoir is a reservoir in San Diego County, Southern California. It is flanked by Otay Mountain to the southeast, the Jamul Mountains to the east, Otay Lakes Road and Upper Otay Reservoir to the north, and the city of Chula Vista to ...

, which is used to supply drinking water to parts of southern San Diego County. The reservoir is also the terminus for Pipeline 3 of the Second San Diego Aqueduct, which delivers water from the

Colorado River The Colorado River ( es, Río Colorado) is one of the principal rivers (along with the Rio Grande) in the Southwestern United States and northern Mexico. The river drains an expansive, arid drainage basin, watershed that encompasses parts of ...

via the

Colorado River Aqueduct The Colorado River Aqueduct, or CRA, is a water conveyance in Southern California in the United States, operated by the Metropolitan Water District of Southern California (MWD). The aqueduct impounds water from the Colorado River at Lake Hav ...

. Its predecessor, the

Lower Otay Dam Lower may refer to: * Lower (surname) * Lower Township, New Jersey *Lower Receiver (firearms) * Lower Wick Gloucestershire, England See also *Nizhny Nizhny (russian: Ни́жний; masculine), Nizhnyaya (; feminine), or Nizhneye (russian: Ни ...

was a "rockhill type", which was completed in 1897; it failed in 1916 following heavy rains. The

Upper Otay Reservoir Upper Otay Reservoir, also called Upper Otay Lake, is a 20-acre artificial lake in San Diego County, California. It was created in 1959 as a hatchery for the propagation and introduction of Florida Largemouth bass. The reservoir has been open to ...

is formed by Upper Otay Dam, built in 1901. The reservoir was established as a

hatchery A hatchery is a facility where eggs are hatched under artificial conditions, especially those of fish, poultry or even turtles. It may be used for ex-situ conservation purposes, i.e. to breed rare or endangered species under controlled cond ...

for the introduction of Florida-strain

largemouth bass The largemouth bass (''Micropterus salmoides'') is a carnivorous freshwater gamefish in the Centrarchidae ( sunfish) family, a species of black bass native to the eastern and central United States, southeastern Canada and northern Mexico, but ...

in 1959. The reservoir was chemically treated first, which killed all of the native

fish Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of li ...

. In 1996, the reservoir was opened to

fishing Fishing is the activity of trying to catch fish. Fish are often caught as wildlife from the natural environment, but may also be caught from stocked bodies of water such as ponds, canals, park wetlands and reservoirs. Fishing techniques inclu ...

, but all fish caught must be released. Since the river is used as a municipal water supply, there is no human contact allowed at either of the Otay Reservoirs. Early testing of manned gliders by noted aviator

John J. Montgomery John Joseph Montgomery (February 15, 1858 – October 31, 1911) was an American inventor, physicist, engineer, and professor at Santa Clara University in Santa Clara, California, who is best known for his invention of controlled heavier-than-air ...

occurred in the region in the late 19th century.

River

Otay Reservoirs

References

Further reading