96-549: Ballona Creek (pronunciation: "Bah-yo-nuh" or "Buy-yo-nah") is an 8.5-mile (13.7 km) 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 ,
192-444: A current to transport materials varies with its velocity , so that torrents with a rapid fall near the sources of rivers can carry down rocks, boulders and large stones , which are by degrees ground by attrition in their onward course into slate , gravel , sand and silt , simultaneously with the gradual reduction in fall, and, consequently, in the transporting force of the current. Accordingly, under ordinary conditions, most of
288-399: A lock has to be provided alongside the weir, or in a side channel, to provide for the passage of vessels. A river is thereby converted into a succession of fairly level reaches rising in steps up-stream, providing still-water navigation comparable to a canal; but it differs from a canal in the introduction of weirs for keeping up the water-level, in the provision for the regular discharge of
384-476: A watershed (called a "divide" in North America) over which rainfall flows down towards the river traversing the lowest part of the valley, whereas the rain falling on the far slope of the watershed flows away to another river draining an adjacent basin. River basins vary in extent according to the configuration of the country, ranging from the insignificant drainage areas of streams rising on high ground very near
480-498: A 1948 report in the Venice Evening Vanguard , "The total area drained by Ballona Creek consists of 86 square miles (220 km) square miles of coastal plain and 74 square miles (190 km) of foothills and plain range from sea level to 250 feet (76 m) and in the mountains from 250 feet (76 m) to 1,550 feet (470 m). The average gradient of the valley floor is about 20 feet per mile (3.8 m/km) and that of
576-520: A 350-pound (160 kg) sea lion made it 3.5 miles (5.6 km) upstream before it got bogged down; the lost pinniped was lassoed by rescuers and returned to the Pacific. A reported Tongva -language ( Takic subgroup of Uto-Aztecan ) placename for the Ballona estuary and wetlands was Pwinukipar , meaning "it is filled with water". An alternative historic Spanish-language place name for the creek reported in
672-529: A cold season, extending from May to October and from November to April in the Northern hemisphere respectively; the rivers are low and moderate floods are of rare occurrence during the warm period, and the rivers are high and subject to occasional heavy floods after a considerable rainfall during the cold period in most years. The only exceptions are rivers which have their sources amongst mountains clad with perpetual snow and are fed by glaciers ; their floods occur in
768-506: A flooded Jefferson Boulevard appeared in the newspaper after a major storm in December 1931; authorities told reporters that Ballona Creek’s peak flow “more than 7000 second feet” went through the channel. Deadly floods in 1934 led officials to temporarily close “small wooden bridges spanning Ballona Creek” to limit potential danger to civilians. The crossings were at Burnside Avenue, Redondo Boulevard, Thurman Avenue and Venice Boulevard. Much of
864-648: A low mountain range surrounded by and rising above the Los Angeles Basin plain in central Los Angeles County , California . The Pacific Ocean is to the west, the Santa Monica Mountains to the north, Downtown Los Angeles to the northeast, and the Palos Verdes Hills to the south—with all easily viewed from the Baldwin Hills. The headwaters of the urban river known as Ballona Creek are in
960-399: A moderate fall and a fair discharge at their lowest stage, for with a large fall the current presents a great impediment to up-stream navigation, and there are generally great variations in water level, and when the discharge becomes very small in the dry season. It is impossible to maintain a sufficient depth of water in the low-water channel. The possibility to secure uniformity of depth in
1056-462: A net effect of flood control in one area coming at the expense of greatly aggravated flooding in another. In addition, studies have shown that stream channelization results in declines of river fish populations. A 1971 study of the Chariton River in northern Missouri , United States, found that the channelized section of the river contained only 13 species of fish, whereas the natural segment of
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#17331071438211152-405: A physical alteration, and maintain public safety. The size of rivers above any tidal limit and their average freshwater discharge are proportionate to the extent of their basins and the amount of rain which, after falling over these basins, reaches the river channels in the bottom of the valleys, by which it is conveyed to the sea. The basin of a river is the expanse of country bounded by
1248-479: A river bed furnishes a simple and efficient means of increasing the discharging capacity of its channel. Such removals will consequently lower the height of floods upstream. Every impediment to the flow, in proportion to its extent, raises the level of the river above it so as to produce the additional artificial fall necessary to convey the flow through the restricted channel, thereby reducing the total available fall. Human intervention sometimes inadvertently modifies
1344-407: A river by lowering the shoals obstructing the channel depends on the nature of the shoals. A soft shoal in the bed of a river is due to deposit from a diminution in velocity of flow, produced by a reduction in fall and by a widening of the channel, or to a loss in concentration of the scour of the main current in passing over from one concave bank to the next on the opposite side. The lowering of such
1440-421: A routine basis. One major reason is to reduce natural erosion ; as a natural waterway curves back and forth, it usually deposits sand and gravel on the inside of the corners where the water flows slowly, and cuts sand, gravel, subsoil , and precious topsoil from the outside corners where it flows rapidly due to a change in direction. Unlike sand and gravel, the topsoil that is eroded does not get deposited on
1536-476: A shoal by dredging merely effects a temporary deepening, for it soon forms again from the causes which produced it. The removal, moreover, of the rocky obstructions at rapids, though increasing the depth and equalizing the flow at these places, produces a lowering of the river above the rapids by facilitating the efflux, which may result in the appearance of fresh shoals at the low stage of the river. Where, however, narrow rocky reefs or other hard shoals stretch across
1632-475: A small population of venomous southern Pacific rattlesnakes live alongside the creek; exercise due caution to protect both the wildlife and visiting humans. According to a 2003 assessment, "Less than one percent of the plant cover observed along the Ballona Creek could be classified as native species." Bottlenose dolphins , harbor seals and California sea lions are occasionally spotted downstream. In 1953,
1728-401: A stream channelization project in one place must be offset by the creation of new wetlands in another, a process known as "mitigation." The major agency involved in the enforcement of this policy is the same Army Corps of Engineers, which for many years was the primary promoter of wide-scale channelization. Often, in the instances where channelization is permitted, boulders may be installed in
1824-493: A stream may be undertaken for several reasons. One is to make a stream more suitable for navigation or for navigation by larger vessels with deep draughts. Another is to restrict water to a certain area of a stream's natural bottom lands so that the bulk of such lands can be made available for agriculture. A third reason is flood control, with the idea of giving a stream a sufficiently large and deep channel so that flooding beyond those limits will be minimal or nonexistent, at least on
1920-469: A stream once it has been dredged is extremely slow, with many streams showing no significant recovery 30 to 40 years after the date of channelization. For the reasons cited above, in recent years stream channelization has been greatly curtailed in the U.S., and in some instances even partially reversed. In 1990 the United States Government published a " no net loss of wetlands" policy, whereby
2016-421: A very variable flow, and end as gently flowing rivers with a comparatively regular discharge. The irregular flow of rivers throughout their course forms one of the main difficulties in devising works for mitigating inundations or for increasing the navigable capabilities of rivers. In tropical countries subject to periodical rains, the rivers are in flood during the rainy season and have hardly any flow during
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#17331071438212112-508: Is a fully-grade separated trail permitting cyclists to ride the entire length without signals or road crossings. However, the path is closed during major rainstorms as portions running beneath bridges are often fully submerged when water levels are high. More than 30 species of fish are present in the Ballona Del Rey harbor and Ballona estuary. The Ballona Wetlands Land Trust offers a free, full-color, online booklet “A Guide to Fish Found in
2208-408: Is generally referred to as canalization . Reducing the length of the channel by substituting straight cuts for a winding course is the only way in which the effective fall can be increased. This involves some loss of capacity in the channel as a whole, and in the case of a large river with a considerable flow it is very difficult to maintain a straight cut owing to the tendency of the current to erode
2304-482: Is liable to be stopped during the descent of high floods, which in many cases rise above the locks; and it is necessarily arrested in cold climates on all rivers by long, severe frosts, and especially by ice. Many small rivers, like the Thames above its tidal limit, have been rendered navigable by canalization, and several fairly large rivers have thereby provided a good depth for vessels for considerable distances inland. Thus
2400-440: Is provided for the discharge of the river as soon as it overflows its banks, while leaving the natural channel unaltered for the ordinary flow. Low embankments may be sufficient where only exceptional summer floods have to be excluded from meadows. Occasionally the embankments are raised high enough to retain the floods during most years, while provision is made for the escape of the rare, exceptionally high floods at special places in
2496-512: Is the case with the smaller river. The fall available in a section of a river approximately corresponds to the slope of the country it traverses; as rivers rise close to the highest part of their basins, generally in hilly regions, their fall is rapid near their source and gradually diminishes, with occasional irregularities, until, in traversing plains along the latter part of their course, their fall usually becomes quite gentle. Accordingly, in large basins, rivers in most cases begin as torrents with
2592-549: 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 climate can be characterized as Mediterranean with average annual rainfall of about 409 millimeters (16 inches). Land use in
2688-617: The GNIS is Sanjón de Agua con Alisos , which roughly translates to “water ditch with sycamores.” ( Aliso is the North American Spanish language word for Platanus racemosa , or Western sycamore, a landmark water-loving, river-bank tree species native to the area. Watercourses or irrigation channels called zanja , zanjón or sanjon are noted throughout southern California and the American Southwest generally.) Ballona Creek
2784-603: The Rhine , the Danube and the Mississippi . River engineering works are only required to prevent changes in the course of the stream, to regulate its depth, and especially to fix the low-water channel and concentrate the flow in it, so as to increase as far as practicable the navigable depth at the lowest stage of the water level. Engineering works to increase the navigability of rivers can only be advantageously undertaken in large rivers with
2880-576: The Trinity Journal : After a walk of seven hours the main body of the detachment reached Camp Latham, and no one who has ever been here can deny but that it is the finest-situated camp and drill ground in the State. The camp is situated on an eminence, one hundred yards from which flows a beautiful stream of sparkling water, about the size of main Weaver Creek , lined with a dense grove of sycamores , and in
2976-685: The restoration or protection of natural characteristics and habitats . Hydromodification encompasses the systematic response to alterations to riverine and non-riverine water bodies such as coastal waters ( estuaries and bays ) and lakes. The U.S. Environmental Protection Agency (EPA) has defined hydromodification as the "alteration of the hydrologic characteristics of coastal and non-coastal waters, which in turn could cause degradation of water resources." River engineering has often resulted in unintended systematic responses, such as reduced habitat for fish and wildlife, and alterations of water temperature and sediment transport patterns. Beginning in
Ballona Creek - Misplaced Pages Continue
3072-522: 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 . Many of these run wholly or partially underground in storm drains that empty into
3168-590: 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. Dry weather urban runoff and storm water, both conveyed by storm drains , are the primary sources of pollution in the riverine coastal estuary. Since Ballona drains about 126 square miles (330 km) of surface area and thousands of street gutters, freeway runoffs, and industrial overflows, its highly toxic waters constitute
3264-433: The 1930s flood-control engineering. A 2011 study determined that as little as two percent of Ballona's water may now come from underground springs, meaning that 98 percent of the creek's flow consists of various forms of runoff throughout the watershed. From northern source to southern mouth (year built in parentheses): Several of these crossings existed as “small wooden bridges” of unknown age before they were replaced in
3360-457: The 1997 movie Volcano , Mike Roark ( Tommy Lee Jones ) destroys a 20-story apartment building in a controlled demolition in order to divert a flowing river of lava into Ballona Creek and thus into the Pacific Ocean. River engineering River engineering is a discipline of civil engineering which studies human intervention in the course, characteristics, or flow of a river with
3456-455: The Army Corps with EPA participation. Rivers whose discharge is liable to become quite small at their low stage, or which have a somewhat large fall, as is usual in the upper part of rivers, cannot be given an adequate depth for navigation purely by works which regulate the flow; their ordinary summer level has to be raised by impounding the flow with weirs at intervals across the channel, while
3552-457: The Ballona estuary through tide gates . The Ballona watershed is estimated to have roughly 35 percent 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
3648-500: The Ballona watershed hosts over 300 bird species, seven amphibians, 30 kinds of reptiles, almost 40 mammals, more than 200 kinds of fungi (including lichens), more than 100 arachnids, and at least 1,000 insects. The creek and wetlands are specifically recognized as an "Important Birding Area" by the Audubon Society . As far as the creek proper, the best birding opportunities are usually west of Lincoln Boulevard . Urban coyotes and
3744-572: The Los Angeles River, and Ballona Creek became a distinct waterway. Around 1820, a mestizo rancher named Augustine Machado claimed a 14,000-acre (57 km) Mexican land grant that stretched from modern-day Culver City to Pico Boulevard in Santa Monica, California. Ballona Creek and Lagoon are named for the Ballona or Paseo de las Carretas ("wagon pass") land grant, dated November 27, 1839. The Machado and Talamantes families, co-grantees of
3840-647: The Lower Ballona Creek and the Ballona Wetlands.” The Los Angeles Department of Beaches and Harbors permits licensed fishing at the north and south jetties; licenses can be purchased at nearby shops ( West Marine , Marina Del Rey Sportfishing or Del Rey Landing). The Ballona Creek jetty is “a good spot for kelp bass , sand bass , and mackerel .” Due to the contaminated nature of the creek ecosystem, warnings are often posted of species of fish which are unsafe for human consumption. In 1950, an upstream reservoir
3936-505: The Po River, taken in 1874 and 1901, show that its bed was materially raised during this period from the confluence of the Ticino to below Caranella , despite the clearance of sediment effected by the rush through breaches. Therefore, the completion of the embankments, together with their raising, would only eventually aggravate the injuries of the inundations they have been designed to prevent, as
Ballona Creek - Misplaced Pages Continue
4032-655: The Santa Monica Mountains, such as above Beverly Hills and flows along the north base of Baldwin Hills through an active geological watergap, on the way to the Pacific Ocean in Santa Monica Bay . La Cienega Boulevard goes through a pass in the ridge of the Baldwin Hills between Inglewood and Culver City, and northeast of Los Angeles International Airport . La Cienega Boulevard is a parkway road passing alongside open space of large private corporate lands with oil wells of
4128-522: The above-ground section of the creek was lined with concrete as part of the flood-control project undertaken by the United States Army Corps of Engineers between 1935 and 1939. Two laborers, Tony Rizzo, a 44-year-old father of six, and Barney Porres, 24, were killed by a mudslide in the channel in 1937. Two other men were injured. A coroner’s jury found that “lack of proper precautions” by flood-control management team were to blame. A contract
4224-569: The area encompassing the Ballona Creek floodplain and the Westchester Bluffs. These indigenous peoples left a large burial ground near the region along the southwest corner of the Ballona Wetlands near the village of Guashna , alternatively spelled Washna. The records of the San Gabriel Mission record recruitment of Tongva from a group of settlements named Washna (also referred to in some historical and scholarly sources as Saa’angna) near
4320-522: The banks and form again a sinuous channel. Even if the cut is preserved by protecting the banks, it is liable to produce changes shoals and raise the flood-level in the channel just below its termination. Nevertheless, where the available fall is exceptionally small, as in land originally reclaimed from the sea, such as the English Fenlands , and where, in consequence, the drainage is in a great measure artificial, straight channels have been formed for
4416-588: The bed of the new channel so that water velocity is slowed, and channels may be deliberately curved as well. In 1990 the U.S. Congress gave the Army Corps a specific mandate to include environmental protection in its mission, and in 1996 it authorized the Corps to undertake restoration projects. The U.S. Clean Water Act regulates certain aspects of channelization by requiring non-Federal entities (i.e. state and local governments, private parties) to obtain permits for dredging and filling operations. Permits are issued by
4512-406: The bottom of a river and present obstacles to the erosion by the current of the soft materials forming the bed of the river above and below, their removal may result in permanent improvement by enabling the river to deepen its bed by natural scour. The capability of a river to provide a waterway for navigation during the summer or throughout the dry season depends on the depth that can be secured in
4608-404: The canalized Seine has secured a navigable depth of 10 1 ⁄ 2 feet (3.2 metres) from its tidal limit up to Paris, a distance of 135 miles, and a depth of 6 3 ⁄ 4 feet (2.06 metres) up to Montereau, 62 miles higher up. As rivers flow onward towards the sea, they experience a considerable diminution in their fall, and a progressive increase in the basin which they drain, owing to
4704-461: The canyon channels is about 200 feet per mile (38 m/km). The longest distance at any given time taken by the water in this drainage system is 17 miles (27 km)." 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
4800-480: The channel at the low stage by low-dipping cross dikes extending from the river banks down the slope and pointing slightly up-stream so as to direct the water flowing over them into a central channel. The needs of navigation may also require that a stable, continuous, navigable channel is prolonged from the navigable river to deep water at the mouth of the estuary . The interaction of river flow and tide needs to be modeled by computer or using scale models, moulded to
4896-496: The channel at the lowest stage. The problem in the dry season is the small discharge and deficiency in scour during this period. A typical solution is to restrict the width of the low-water channel, concentrate all of the flow in it, and also to fix its position so that it is scoured out every year by the floods which follow the deepest part of the bed along the line of the strongest current. This can be effected by closing subsidiary low-water channels with dikes across them, and narrowing
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#17331071438214992-449: The channelization of Florida's Kissimmee River has been cited as a cause contributing to the loss of wetlands. This straightening causes the streams to flow more rapidly, which can, in some instances, vastly increase soil erosion. It can also increase flooding downstream from the channelized area, as larger volumes of water traveling more rapidly than normal can reach choke points over a shorter period of time than they otherwise would, with
5088-433: The coast and flowing straight down into the sea, up to immense tracts of great continents, where rivers rising on the slopes of mountain ranges far inland have to traverse vast stretches of valleys and plains before reaching the ocean. The size of the largest river basin of any country depends on the extent of the continent in which it is situated, its position in relation to the hilly regions in which rivers generally arise and
5184-416: The compulsory raising of their gates for the passage of floods, the removal of fish traps , which are frequently blocked up by leaves and floating rubbish, reduction in the number and width of bridge piers when rebuilt, and the substitution of movable weirs for solid weirs. By installing gauges in a fairly large river and its tributaries at suitable points, and keeping continuous records for some time of
5280-456: The configuration of the estuary under consideration and reproducing in miniature the tidal ebb and flow and fresh-water discharge over a bed of very fine sand, in which various lines of training walls can be successively inserted. The models should be capable of furnishing valuable indications of the respective effects and comparative merits of the different schemes proposed for works. Baldwin Hills (mountain range) The Baldwin Hills are
5376-406: The course or characteristics of a river, for example by introducing obstructions such as mining refuse, sluice gates for mills, fish-traps, unduly wide piers for bridges and solid weirs . By impeding flow these measures can raise the flood-level upstream. Regulations for the management of rivers may include stringent prohibitions with regard to pollution , requirements for enlarging sluice-ways and
5472-672: The creek require constant cleanup by the County Department of Public Works and volunteer teams. Fifty bags of litter, including diapers, syringes and a car bumper, were removed from Ballona Creek on Coastal Cleanup Day in 1988. Two abandoned live kittens along with 67,000 pounds (30,000 kg) of dumped garbage were removed in 2002. Nets and booms strung across the end of the creek attempt to catch as much litter as possible before it enters Santa Monica Bay . Grocery-store carts and trash litter [Ballona Creek], joined by flotillas of foam-plastic cups after rainstorms. Another observer described
5568-409: The creek was put into agricultural use alongside new small towns such as Venice (est. 1905) and Culver City (est. 1917). In 1928, one writer observed, “Gradually Rancho La Ballona began to develop and people began to build. The ranches were subdivided until Rancho la Ballona became a rich valley of beautiful homes with people coming from every State until it reaches the portions of today.” Photos of
5664-569: The creek, and I catch a pelican diving into the water mid-flight. LA County Public Works deployed an Interceptor Original, a solar-powered, automated system made by the Dutch nonprofit The Ocean Cleanup , near the mouth of the creek in October 2022. This is the first Interceptor Original installed in the United States, and the second of the third-generation Interceptor Original to be deployed globally. Until
5760-724: The creek. 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 (Area C—State lands), Bluff Creek and Ballona Wetlands , Marina del Rey (including Marina Del Rey Wetland Park ), and Oxford Flood Control Basin . Ballona Wetlands, Del Rey Lagoon, Ballona Lagoon and Oxford Basin are connected to
5856-523: 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 ." "Ballona Watershed Map" . The Ballona Creek watershed totals about 130 square miles (340 square kilometers). According to
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#17331071438215952-725: The danger of flooding downstream. In the Midwestern United States and the Southern United States the term for this measure is channelization. Much of it was done under the auspices or overall direction of the United States Army Corps of Engineers . One of the most heavily channelized areas in the United States is West Tennessee , where every major stream with one exception (the Hatchie River ) has been partially or completely channelized. Channelization of
6048-410: The embankments, where the scour of the issuing current is guarded against, and the inundation of the neighboring land is least injurious. In this manner, the increased cost of embankments raised above the highest flood-level of rare occurrence is avoided, as is the danger of breaches in the banks from an unusually high flood-rise and rapid flow, with their disastrous effects. A most serious objection to
6144-463: The escape of floods from the raised river must occur sooner or later. In the UK, problems of flooding of domestic properties around the turn of the 21st century have been blamed on inadequate planning controls which have permitted development on floodplains. This exposes the properties on the floodplain to flood, and the substitution of concrete for natural strata speeds the run-off of water, which increases
6240-541: The expenditure involved where significant assets (such as a town) are under threat. Additionally, even when successful, such floodworks may simply move the problem further downstream and threaten some other town. Recent floodworks in Europe have included restoration of natural floodplains and winding courses, so that floodwater is held back and released more slowly. The removal of obstructions, natural or artificial (e.g., trunks of trees, boulders and accumulations of gravel) from
6336-430: The formation of continuous, high embankments along rivers bringing down considerable quantities of detritus, especially near a place where their fall has been abruptly reduced by descending from mountain slopes onto alluvial plains, is the danger of their bed being raised by deposit, producing a rise in the flood-level, and necessitating a raising of the embankments if inundations are to be prevented. Longitudinal sections of
6432-444: The general state of the creek in 2021: What little water there is flows heavy with trash and the rainbow glints of motor oil…Graffiti lines every overpass. Water, flowing from god-knows-where above, leaks yellow-green across the street. Mountains of collected dross mark an impromptu home… This place has a sort of decaying beauty, like the moody ruins of a romanticist oil painting. As the miles roll by nature slowly returns. Brush lines
6528-403: The heights of the water at the various stations, the rise of the floods in the different tributaries, the periods they take in passing down to definite stations on the main river, and the influence they severally exercise on the height of the floods at these places, can be ascertained. With the help of these records, and by observing the times and heights of the maximum rise of a particular flood at
6624-465: The immediate vicinity of camp is a pretty grove of willows , planted tastefully by an old Spaniard, and which is beginning to form a pleasant retreat for the inhabitants of the neighborhood, and the troops at this point. In 1886, a California state report described Ballona and Centinela creeks: Circa 1890, the renowned Machado ranch stables were located "a few hundred feet across the Ballona bridge on Overland Avenue." A 1912 advertisement for homes in
6720-400: The impending inundation. Where portions of a riverside town are situated below the maximum flood-level, or when it is important to protect land adjoining a river from inundations, the overflow of the river must be diverted into a flood-dam or confined within continuous embankments on both sides. By placing these embankments somewhat back from the margin of the river-bed, a wide flood-channel
6816-402: The inside of the next corner of the river. It simply washes away. Channelization has several predictable and negative effects. One of them is loss of wetlands . Wetlands are an excellent habitat for many forms of wildlife, and additionally serve as a "filter" for much of the world's surface fresh water. Another is the fact that channelized streams are almost invariably straightened. For example,
6912-620: The intention of producing some defined benefit. People have intervened in the natural course and behaviour of rivers since before recorded history—to manage the water resources , to protect against flooding , or to make passage along or across rivers easier. Since the Yuan Dynasty and Ancient Roman times, rivers have been used as a source of hydropower . From the late 20th century, the practice of river engineering has responded to environmental concerns broader than immediate human benefit. Some river engineering projects have focused exclusively on
7008-572: The late 20th century, the river engineering discipline has been more focused on repairing hydromodified degradations and accounting for potential systematic response to planned alterations by considering fluvial geomorphology . Fluvial geomorphology is the study of how rivers change their form over time. Fluvial geomorphology is the cumulation of a number of sciences including open channel hydraulics , sediment transport , hydrology , physical geology, and riparian ecology. River engineering practitioners attempt to understand fluvial geomorphology, implement
7104-577: The low stage of the Saône flowing into the Rhone at Lyon, which has its floods in the winter when the Arve, on the contrary, is low. Another serious obstacle encountered in river engineering consists in the large quantity of detritus they bring down in flood-time, derived mainly from the disintegration of the surface layers of the hills and slopes in the upper parts of the valleys by glaciers, frost and rain. The power of
7200-539: The materials brought down from the high lands by torrential water courses are carried forward by the main river to the sea, or partially strewn over flat alluvial plains during floods; the size of the materials forming the bed of the river or borne along by the stream is gradually reduced on proceeding seawards, so that in the Po River in Italy, for instance, pebbles and gravel are found for about 140 miles below Turin , sand along
7296-580: The most serious source of pollution for Santa Monica Bay. "A new city sewer line in the 1980s alleviated some, but not all, of the problem." The urbanization of the watershed, and associated with it the pollution of urban runoff and stormwater , has degraded the water quality in Ballona Creek and its estuary . Ballona Creek is listed by the Los Angeles Regional Water Quality Control Board impaired for fecal coliform , heavy metals , and pesticides . The litter flows into
7392-518: The mouth of Ballona Creek. Before the Spanish conquest, Washna was probably the most important Native American center for trade between the mainland and Catalina Island. The Spanish Portolá expedition camped at the headwaters of Ballona on August 3, 1769. At the time of Spanish settlement, Ballona Creek was a distributary of the Los Angeles River . However, the flood of 1825 changed the course of
7488-445: The next 100 miles, and silt and mud in the last 110 miles (176 km). Improvements can be divided into those that are aimed at improving the flow of the river, particularly in flood conditions, and those that aim to hold back the flow, primarily for navigation purposes, although power generation is often an important factor. The former is known in the US as channelization and the latter
7584-646: The oldest and most extensive water redistribution projects in the United States.” When the Baldwin Hills Dam broke 1963, the Ballona Creek Channel carried the flood of water and debris safely to the sea. The Ballona Creek Bike Path , which extends almost 7 miles (11 km) from National Boulevard in Culver City to Marina Del Rey, is a popular fitness track. Running along a combination of existing flood control service roadways and purpose-built paths, it
7680-455: The rancho, heralded from Baiona in northern Spain. In the 1840s, Francisco Higuera's adobe was "close enough to La Ballona Creek for Francisco's nine children to swim in the clear waters of the stream with its fine sandy bottom." From 1861 to 1862 the creek was home to an U.S. Army staging ground. Several soldiers posted to Camp Latham described the local vistas, including "Charley" in May 1862 in
7776-409: The rest of the year, while in temperate regions, where the rainfall is more evenly distributed throughout the year, evaporation causes the available rainfall to be much less in hot summer weather than in the winter months, so that the rivers fall to their low stage in the summer and are very liable to be in flood in the winter. In fact, with a temperate climate, the year may be divided into a warm and
7872-450: The river at the weirs, and in the two sills of the locks being laid at the same level instead of the upper sill being raised above the lower one to the extent of the rise at the lock, as usual on canals. Canalization secures a definite available depth for navigation; and the discharge of the river generally is amply sufficient for maintaining the impounded water level, as well as providing the necessary water for locking. Navigation, however,
7968-571: The river to undergo maintenance and upgrades, with a plan to reinstall it in time for the 2024 winter storm season. The watershed as a whole, which stretches from the Skirball Center to Griffith Park (south of the SM Mountains ridgeline) down past Echo Park to south Los Angeles , then back past the Baldwin Hills , over to the coast between Ocean Park and Playa Del Rey , supports an estimated 3,000 species of flora, fauna, and fungi. All told
8064-428: The rivers. Because of the perceived value in protecting these fertile, low-lying lands from inundation, additional straight channels have also been provided for the discharge of rainfall, known as drains in the fens. Even extensive modification of the course of a river combined with an enlargement of its channel often produces only a limited reduction in flood damage. Consequently, such floodworks are only commensurate with
8160-508: 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 (I-110) to the east. Before colonization, the Tongva village of Guashna located at the mouth of
8256-414: The sea into which they flow, and the distance between the source and the outlet into the sea of the river draining it. The rate of flow of rivers depends mainly upon their fall, also known as the gradient or slope. When two rivers of different sizes have the same fall, the larger river has the quicker flow, as its retardation by friction against its bed and banks is less in proportion to its volume than
8352-438: The stations on the various tributaries, the time of arrival and height of the top of the flood at any station on the main river can be predicted with remarkable accuracy two or more days beforehand. By communicating these particulars about a high flood to places on the lower river, weir-keepers are enabled to fully open the movable weirs beforehand to permit the passage of the flood, and riparian inhabitants receive timely warning of
8448-423: The stream was home to 21 species of fish. The biomass of fish able to be caught in the dredged segments of the river was 80 percent less than in the natural parts of the same stream. This loss of fish diversity and abundance is thought to occur because of reduction in habitat, elimination of riffles and pools, greater fluctuation of stream levels and water temperature, and shifting substrates. The rate of recovery for
8544-411: The successive influx of their various tributaries. Thus, their current gradually becomes more gentle and their discharge larger in volume and less subject to abrupt variations; and, consequently, they become more suitable for navigation. Eventually, large rivers, under favorable conditions, often furnish important natural highways for inland navigation in the lower portion of their course, as, for instance,
8640-550: The summer from the melting of snow and ice, as exemplified by the Rhône above the Lake of Geneva , and the Arve which joins it below. But even these rivers are liable to have their flow modified by the influx of tributaries subject to different conditions, so that the Rhone below Lyon has a more uniform discharge than most rivers, as the summer floods of the Arve are counteracted to a great extent by
8736-557: The system was put into place, it was docked with the United States Coast Guard in Long Beach, California . One boom on the device was damaged in the 2022-2023 storms but the main unit was not damaged. The trash interceptor completed its two year pilot program in October 2024 and was considered a success, capturing nearly 124 tons of total material, 2,738 pounds of that being recyclable material. The system will be removed from
8832-411: The watershed consists of 64 percent residential, 17 percent open space, eight percent commercial, and four percent industrial. The flow rate in the creek varies considerably, from a trickle flow of about 14 cubic feet (0.40 cubic metres) per second during dry weather to 71,400 cu ft (2,020 m) per second (see cubic meters per second ) during a 50-year storm event. Note: In Los Angeles County,
8928-516: The “Washington Park subdivision” along the creek said, “Ballona Creek is a swift-running little stream, fed by springs, and carrying plenty of water all the year. It divides in Washington Park, making a picturesque little island.” In addition to other festivities organized by real-estate brokers to drum sales in the new development, “A free luncheon with hot coffee was served on Ballona Island, the wooded island in Ballona Creek.” The ranch land along
9024-527: Was a picturesque natural waterway fed by runoff. The creek collected the water from ciénegas and the rains. Its banks were lined with sycamores, willows, tules , and other trees. This natural bounty attracted the earliest known human inhabitants of the region, the Gabrieliño- Tongva Indians, the indigenous people of the Los Angeles region. For at least 3,000 years, the pre-Contact Tongva lived in
9120-431: Was awarded in 1946 to extend the stone jetties an additional 550 feet (170 m) “to deflect ocean currents to prevent beach erosion.” The tributaries were channelized in the 1950s. Centinela Creek’s course was set in parallel to the route of Interstate 405 and the then-forthcoming Marina Freeway . The channelization of the creek is part of the larger human reorganization of southern California hydrology , “some of
9216-454: Was being drained by Los Angeles, and “Bass and blue gill , stocked in the reservoir, ran down storm drains and into Ballona Creek.” The Culver City Chamber of Commerce and Hughes Aircraft Rod & Gun Club erected a temporary dam to trap the fish and threw a fishing contest for local kids. (No adults allowed.) The Little Rascals of Hal Roach ’s Our Gang used Ballona Creek as a filming location for shorts like “ Fish Hooky ” (1933). In
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