Ballona Creek


Ballona Creek is an channelized stream in southwestern Los Angeles County, California, United States, that was once a "year-round river lined with sycamores and willows". The urban watercourse begins in the Mid-City neighborhood of Los Angeles, flows through Culver City and Del Rey, and passes the Ballona Wetlands Ecological Preserve, the sailboat harbor Marina del Rey, and the small beachside community of Playa del Rey before draining into Santa Monica Bay. The Ballona Creek drainage basin carries water from the Santa Monica Mountains on the north, from the Baldwin Hills to the south, and as far as the Harbor Freeway to the east.
Before colonization, the Tongva village of Guashna was located at the mouth of the creek. Ballona Creek and neighboring Ballona Wetlands remain a prime bird-watching spot for waterfowl, shorebirds, warblers, and birds of prey. In 1982, film critic Richard von Busack, a native of Culver City, described the channelized creek as "a cement drainage ditch indistinguishable in size and content from the Love Canal."

Watershed and course

The Ballona Creek watershed totals about. According to a 1948 report in the Venice Evening Vanguard, "The total area drained by Ballona Creek consists of square miles of coastal plain and of foothills and plain range from sea level to and in the mountains from to. The average gradient of the valley floor is about and that of the canyon channels is about. The longest distance at any given time taken by the water in this drainage system is." Before most of Los Angeles' watercourses were buried underground, Ballona Creek drained the whole of the west Los Angeles region and fed directly from a chain of ciénegas and lakes that stretched from the Hollywood Hills to the Baldwin Hills.
The major tributaries to the Ballona Creek and estuary include Centinela Creek channel, Sepulveda Creek channel, and Benedict Canyon channel; most of the creek's natural minor tributaries have been destroyed by development or paved over and flow into Ballona Creek as a network of underground storm drains.
Ballona Creek watershed's climate can be characterized as Mediterranean with average annual rainfall of about. Land use in the watershed is 64% residential, 17% open space, 8% commercial, and 4% industrial. The flow rate in the creek varies considerably, from a trickle flow of about per second during dry weather to per second during a 50-year storm event. Note: In Los Angeles County, the "water year" is measured beginning October 1 continuing until the next September 30, rather than by calendar year.
Natural channels remain at some of the headwaters of Ballona Creek tributaries, while the lower portion of the stream is encased in concrete channels either rectangular in the east or trapezoidal toward the west; to the west of Centinela Avenue, the bottom of the creek is unpaved and subject to tidal influence.

Tributaries and drains

  • Brush Canyon Creek – an intermittent stream, about long, begins in what everyone calls Bronson Canyon, roughly between the Hollywood Reservoir and Mount Hollywood, travels south, passes under Wilshire Country Club, enters the Arroyo de los Jardines, through the Brookside neighborhood of Hancock Park
  • Arroyo de la Sacatela – Shakespeare Bridge in Franklin Hills–Los Feliz was built to cross this watercourse, which fed Bimini Slough in what is now Koreatown; infrastructure built 1929 drained a area, which among other things permitted development of land below Santa Monica Boulevard between Mariposa and Kenmore
  • Ferndell in Griffith Park
  • Laurel Canyon Creek – an intermittent stream, about long, draining a small area in the Santa Monica Mountains and flowing southward into Ballona Creek through La Brea Rancho
  • Nichols Canyon Creek – an intermittent stream, long, draining a small area in the eastern part of the Santa Monica Mountains and discharging southward into Ballona Creek through La Brea Rancho
  • Arroyo de Los Jardines – According to a 1937 news report, "Nearly all of the flood waters from Hollywood business and residential district eventually find their way into the Arroyo de Los Jardines channel, concentrating near Wilshire Boulevard and La Brea Avenue. The county flood control district has prepared a $361,000 plan to build a new and adequate channel for the Arroyo de Los Jardines between Wilshire and Ballona Creek. The water will pour into Ballona Creek, two blocks west of La Brea Avenue. Water from Nichols Canyon also reaches Ballona Creek by way of the Arroyo de Los Jardines."
  • Dry Canyon Creek – an intermittent stream, about long, draining a small area in the Santa Monica Mountains and flowing southeastward to San Jose de Buenos Ayres Rancho
  • Benedict Canyon Channel – constructed by the U.S. Army Corps of Engineers in 1961–62
  • * Benedict Canyon Creek – an intermittent stream, long, draining a small area in the Santa Monica Mountains, and flowing southward into Rodeo de las Aguas Rancho
  • * Coldwater Canyon Creek – an intermittent stream, long, draining a small area in the Santa Monica Mountains, and flowing southward and southeastward into Rodeo de las Aguas Rancho. Near the mouth of its canyon it receives streams draining Franklin and Higgins canyons.
  • ** Higgins Canyon Creek – an intermittent stream, about long
  • ** Franklin Canyon Creek – an intermittent stream, about long, draining a small area in the Santa Monica Mountains and flowing southward to its junction with Coldwater Canyon Creek
  • * Peavine Canyon Creek – an intermittent stream, about long, draining a small area in the Santa Monica Mountains and flowing southward to the mouth of its canyon near what is now Beverly Hills – essentially San Ysidro Drive
  • Sepulveda Canyon Creek – an intermittent stream, about long, draining a small area in the Santa Monica Mountains and flowing southeastward toward Ballona Creek; sinks north of the VA in Brentwood
  • * Sawtelle-Westwood Channel, plan in 1934 was a "large conduit from Pico Boulevard to Venice Boulevard and eventually southward to Ballona Channel"; construction began 1956
  • * Sepulveda Channel – sometimes called the Mar Vista drain, initial plans in 1927 were for it to begin at Midvale and Pico
  • ** Stone Canyon Creek – an intermittent stream, about long, draining a small area in the Santa Monica Mountains and flowing southward into Westwood – still accessible on UCLA campus between Sunset Boulevard and the Anderson School of Management
  • Brown Canyon Creek – an intermittent stream, about long, draining a small area in the Santa Monica Mountains, and flowing east of south to a point near Palms, where its waters would sink or might feed into Ballona during particularly wet yearscreek recently daylighted as part of the Westwood Greenway adjacent to Westwood/Rancho Park station
  • Centinela Creek Channel – ancient waterway, channelized in mid-20th century; rises near Centinela Park ; surfaces near La Tijera Boulevard, flows northwestward about to Mesmer, then follows the route of the 90 freeway until it meets Ballona Creek; before channelization and the creation of Marina del Rey, fed into Ballona Lagoon
  • Adams Channel – one 1905 article about the city water supply surmised that the original course of the Los Angeles River was roughly along what is now Adams Boulevard. The West Adams storm drain was built in 1925 and started at Vermont Avenue – a segment of the "West Adams sewer" under construction in 1926 presented "unusual engineering difficulties, it is said, because water is found within a few feet of the surface in almost the entire territory, which extends from Angeles Mesa drive to the end of West Adams street and on either side of that street from Washington to Jefferson streets".
  • Rexford Channel
  • North Culver Drain
Many of these run wholly or partially underground in storm drains that empty into the creek.

Additional watershed elements

According to a report from the Los Angeles Department of Water and Power, other contributing elements of the contemporary watershed, besides the major tributaries, are Baldwin Hills Park, Del Rey Lagoon Park, Ballona Lagoon Marine Preserve, Grand Canal, the Venice Canals, Ballona Northeast, Bluff Creek and Ballona Wetlands, Marina del Rey, and Oxford Flood Control Basin.
Ballona Wetlands, Del Rey Lagoon, Ballona Lagoon, and Oxford Basin are connected to the Ballona estuary through tide gates.
The Ballona watershed is estimated to have roughly 35% impervious surface, which affects rainwater infiltration and groundwater recharge.
There were at least 41 natural springs mapped in the Río de La Ballona watershed before development. A waterway called Walnut Creek once arose near what is now the L.A. Coliseum at Exposition, but it was destroyed by the 1930s flood-control engineering.
A 2011 study determined that as little as 2% of Ballona's water may now come from underground springs, meaning that 98% of the creek's flow consists of various forms of runoff throughout the watershed.

Crossings

From northern source to southern mouth :
File:Three bridges over Ballona Creek.jpg|thumb|Three bridges over Ballona Creek: Expo Bike Path to the left, E Line track overhead, and long-derelict Pacific Electric Santa Monica Air Line route to the right; with bypassing jogger on Ballona Creek Bike Path below.
Several of these crossings existed as “small wooden bridges” of unknown age before they were replaced in the 1930s by WPA infrastructure projects. An “old wooden bridge” was in place on Overland before 1928. A 1900 railway map appears to show Ballona Creek crossings at Inglewood, Higuera, and La Cienega, and a crossing between Alla and Alsace stations.