Chollas Creek is an urban creek in San Diego County, California, United States, that drains to the San Diego Bay. It is also referred to as Las Chollas Creek. Chollas Creek arises in Lemon Grove and La Mesa, where its four branches begin. It empties into the Bay at Barrio Logan. The creek is long. The creek splits into two main forks and may be dry during the Southern California dry season. Multiple plant, animal, and aquatic wildlife species live in or around the creek, including the rare plants Juncus acutus leopoldii and Iva hayesiana, and the threatened Coastal California gnatcatcher.
The creek has been in existence since before 1500 BC, and it was used by the Kumeyaay, who had a village by the creek. By 1841, the Kumeyaay village was no longer present on the creek. The creek has flooded several times, affecting people living nearby. Portions of the creek have been armored or channelized. A dam was constructed on a tributary in the early 20th century, forming Chollas Reservoir. The presence of the reservoir led the United States Navy to construct the Chollas Heights Navy Radio Station to the north.
The Chollas Creek valley has been described as "one of San Diego's most neglected watersheds." For decades the creek has been plagued by pollution, illegal dumping, and the destruction of natural habitats. It is an "impaired" water body because of high levels of pollutants. In 2002, the City of San Diego began a plan to rehabilitate the creek. In 2021, a plan to make the creek area into a regional park was adopted.
Geography
The Chollas Creek watershed extends from the cities of La Mesa, Lemon Grove, into San Diego largely south of Interstate 8, as well as from an area unincorporated San Diego County. It also runs through City Heights, Encanto, Barrio Logan, and eastern and southeastern San Diego. The highest elevation of the creek is within La Mesa at about . The creek currently empties into San Diego Bay within Naval Station San Diego.
Hydrology
The watershed of Chollas Creek is in area, split into two main forks. The cumulative length of those two forks is linearly. The south fork watershed covers an area of , and the north fork watershed covers an area of . When rain does not fall within the creek's watershed the creek is usually dry except for what urban runoff occurs. Due to significant urbanization of the watershed, most of the existing soils within it are not very permeable, this leads to increased volume and velocity of water during storms which has resulted in erosion of land impacting habitat and existing infrastructure. Maximum discharge predicted from the creek when it goes under Main Street, near Naval Station San Diego, is per second. Only a small portion of the watershed are tidelands, and fall under the jurisdiction of the Port of San Diego or the United States Navy. During the months of May to September, Southern California's dry season, the creek may be dry or have very little flow. The mile of the creek closest to San Diego Bay is tidally influenced.
Flora and fauna
In the late 19th century, thickets of cactus as tall as nearly six feet high were noted in the valley created by the creek. Other species of plants observed growing abundantly included Arctostaphylos, Ceanothus, Eriodictyon californicum, Vitis girdiana, and Diplacus aurantiacus.
By the late 20th century, species of plant found along the creek were Eriogonum fasciculatum, Salvia apiana, Quercus dumosa, Malosma, and Diplacus aurantiacus. In 2015, a study of the south fork of the creek, before it merged with the north fork, found that two plant species with California Rare Plant Ranks were found: Juncus acutus leopoldii, and Iva hayesiana.
A study at the mouth of Chollas Creek in 2015 found four species of bivalves, and one species of gastropod. The most numerous bivalve was a species of chione.
Birds commonly found along Chollas Creek include the California gnatcatcher, red-tailed hawk, Bell's vireo, and cactus wren. Of these species the Coastal California gnatcatcher is a threatened species.
Wildlife that live around the creek can include coyotes, skunks, possums, and red-shouldered hawk. Other wildlife which might be found around the creek include desert cottontail, gray foxes, and big brown bats.
History
Chollas Creek's existence is estimated to date back to at least 1500 BC, with wetland environment dominating the mouth of the creek by 0 AD at the latest. By 1000 AD at the latest, a sandy beach was formed at the northwest mouth of the creek.
Native American history
Chollas Creek was utilized by the Kumeyaay prior to the arrival of the Spanish.