The Alamo Canal ( es, Canal del Álamo) was a long waterway that connected 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 watershed that encompasses parts of seven U.S. sta ...

to the head of the

Alamo River The Alamo River ( es, Río Álamo) flows west and north from the Mexicali Valley (Baja California) across the Imperial Valley ( California). The river drains into the Salton Sea. The New River, Alamo River, and the Salton Sea of the 21st centur ...

. The canal was constructed to provide irrigation to the

Imperial Valley , photo = Salton Sea from Space.jpg , photo_caption = The Imperial Valley below the Salton Sea. The US-Mexican border runs diagonally across the lower left of the image. , map_image = Newriverwatershed-1-.jpg , map_caption = Map of Imperial ...

. A small portion of the canal was located in the United States but the majority of the canal was located in Mexico. The Alamo Canal is also known as the Imperial Canal.

Planning and construction

Historically, the Colorado River flowed to the Gulf of California, however in times of the spring floods the Colorado River would overflow its banks and also drain into the Alamo River. Flow from the Alamo River then drained to the

Salton Sink The Salton Sink is the low point of an endorheic basin, a closed drainage system with no outflows to other bodies of water, in the Colorado Desert sub-region of the Sonoran Desert. The sink falls within the larger Salton Trough and separates th ...

area of the

Colorado Desert California's Colorado Desert is a part of the larger Sonoran Desert. It encompasses approximately , including the heavily irrigated Coachella and Imperial valleys. It is home to many unique flora and fauna. Geography and geology The Colorado ...

. Such overflow had been observed in 1884, 1891, 1892, and 1895. In the mid- to late-Nineteenth Century several individuals, most notably

O. M. Wozencraft Oliver M. Wozencraft (July 26, 1814 – November 22, 1887) was a prominent early American settler in California. He had substantial involvement in negotiating treaties between California Native American Indian tribes and the United States ...

, proposed irrigating the Salton Sink by diverting a controlled gravity-fed flow of the Colorado River through the existing dry Alamo River bed. The Alamo Canal was the first attempt to create that diversion. It was engineered by

George Chaffey George Chaffey (28 January 1848 – 1 March 1932) was a Canadian–born engineer who with his brother William developed large parts of Southern California, including what became the community of Etiwanda and cities of Ontario, and Upland. They ...

of the

California Development Company The California Development Company was formed in 1896 as a replacement for the defunct Colorado River Irrigation Company, which had been started a few years earlier for the purpose of planning an irrigation system for the lower Colorado Desert in ...

starting in 1900. The canal intake and temporary wooden headgates (known as the Chaffey Gate) were initially located in the United States at Pilot Knob due to the availability of a solid rock foundation. The canal then crossed the border with Mexico and ran parallel to the Colorado River for approximately , where a channel was cut several miles west to the head of the Alamo River. This path was selected to avoid the expensive engineering that would otherwise be required if the canal were to traverse the

Algodones Dunes The Algodones Dunes is a large sand dune field, or erg, located in the southeastern portion of the U.S. state of California, near the border with Arizona and the Mexican state of Baja California. The field is approximately long by wide and ...

. A small amount of irrigation water was first delivered to the Imperial Valley in 1901, with larger flows becoming available in 1902. In 1906 work was completed on the permanent concrete headgates at Hanlon Heading.

Creation of the Salton Sea

Colorado River below Imperial Canal intake

In 1904 heavy silting greatly reduced the water-carrying capacity of the canal. Imperial Valley farmers, under considerable financial stress, pressured the California Development Company to resolve the problem. Charles Rockwood, faced with bankruptcy and "after mature deliberation", directed the engineering of a breach in the bank of the Colorado River approximately south of the existing wooden headgates (the Chaffey Gate). The breach, known as the Lower Mexican Intake, and constructed without headgates and without the permission of the Mexican authorities, allowed the Colorado River to flow unimpeded into the canal, and then to Imperial Valley farms. During the subsequent seasonal floods of 1904 through to late 1906, a large amount of the water carried in the Colorado River flowed directly into the Salton Sink. At various times during this period the entirety of the Colorado River was diverted into the canal. Rockwood's action in ordering the breach was later described as a "blunder so serious as to be practically criminal." Multiple failed attempts were made to close the diversion and establish a controlled flow via headgates. On February 11, 1907, the breach was finally closed after substantial intervention by the Southern Pacific Transportation Company.

Legacy and replacement

ALL-AMERICAN CANAL CARRIES COLORADO RIVER WATER THROUGH SAND-SWEPT AREA OF THE IMPERIAL VALLEY - NARA - 549076

The rate of water loss through aquifer replenishment and evaporation in the Salton Sink was much less than the massive inflow of the Colorado River via the third diversion of the Alamo Canal (the "Lower Mexican Intake"). As a direct result of the decision to create canal intakes from the Colorado River without headgates the

Salton Sea The Salton Sea is a shallow, landlocked, highly saline body of water in Riverside and Imperial counties at the southern end of the U.S. state of California. It lies on the San Andreas Fault within the Salton Trough that stretches to the Gulf ...

was formed. Ongoing provision of water to the Imperial Valley from the Alamo Canal ensured that the Salton Sea would remain intact through the lifetime of the canal. The initial flooding of the Salton Sink destroyed the New Liverpool Salt Company works. On January 10, 1908, the owners of the works were awarded a judgement against the California Development Company of $458,246.23. Southern Pacific, which incurred considerable costs repairing the breaches, held a judgment against California Development of $3,772,128.52. By June, 1915 a total of $5,049,554.78 was owed to creditors, with most of those costs and judgments directly related to the failure of the canal. This debt triggered the bankruptcy of California Development, with all assets passed to Southern Pacific. In 1911 Imperial Valley farmers formed the

Imperial Irrigation District The Imperial Irrigation District (IID) is an irrigation district that serves the Imperial Valley in Southern California. Established under the State Water Code, the IID supplies roughly of Imperial Valley farmland with raw Colorado River wate ...

. By 1916 the Imperial Irrigation District had purchased all the ex-California Development assets from Southern Pacific and assumed operation of the canal. Construction of the

All-American Canal The All-American Canal is an long aqueduct, located in southeastern California. It conveys water from the Colorado River into the Imperial Valley and to nine cities. It is the Imperial Valley's only water source, and replaced the Alamo Canal, w ...

was completed in 1940. By 1942 the All-American Canal was the sole canal providing Colorado River water to the Imperial Valley.

Images

File:Alamo Canal 1908.png , Alamo Canal construction and diversion history, as of 1908. File:Canal full with water from the Colorado River, ca.1903 (CHS-4264).jpg, Alamo Canal 1903. File:Alamo Canal Heading 3 Dike 1905.jpg , A crew erecting a dike at the third heading of the Alamo Canal in Mexico, 1905. File:Alamo Canal Hanlon Heading.jpg , Disused Alamo Canal headgates at Hanlon Heading. The first headgates, known as the Chaffey Gate, were located approximately south of this point.

References

External links