Alamo Canal
Encyclopedia
The Alamo Canal was a 14 miles (22.5 km) long waterway that connected the Colorado River
to the head of the Alamo River
. The canal was constructed to provide irrigation to the Imperial Valley
. 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.
, however in times of flood 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
area of the Colorado Desert
. 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
, 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
of the California Development Company
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 4 miles (6.4 km), 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
.
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.
. These rivers drained to the endorheic Salton Sink.
The engineering attempts to allow a reasonable flow in the canal due to silting included the creation of three diversions without headgates; the first in the US, and then two in Mexico. The third diversion, created in October 1904, eventually channeled massive uncontrolled quantities of water into the canal during and after the subsequent seasonal floods of the Colorado River.
Multiple failed attempts were made to close the diversions and establish a controlled flow via headgates. On January 27, 1907 the flooding was finally stopped after substantial intervention by the Southern Pacific Company.
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 judgement 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 judgements 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
. 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
was completed in 1940. By 1942 the All-American Canal was the sole canal providing Colorado River water to the Imperial Valley.
Colorado River
The Colorado River , is a river in the Southwestern United States and northwestern Mexico, approximately long, draining a part of the arid regions on the western slope of the Rocky Mountains. The watershed of the Colorado River covers in parts of seven U.S. states and two Mexican states...
to the head of the Alamo River
Alamo River
The Alamo River is a river flowing west and north from the Mexicali Valley across the Imperial Valley . The river drains into the Salton Sea....
. The canal was constructed to provide irrigation to the Imperial Valley
Imperial Valley
The Imperial Valley is an agricultural area of Southern California's Imperial County. It is located in southeastern Southern California, centered around the city of El Centro. Locally, the terms "Imperial Valley" and "Imperial County" are used synonymously. The Valley is bordered between the...
. A small portion of the canal was located in the United States
United States
The United States of America is a federal constitutional republic comprising fifty states and a federal district...
but the majority of the canal was located in Mexico
Mexico
The United Mexican States , commonly known as Mexico , is a federal constitutional republic in North America. It is bordered on the north by the United States; on the south and west by the Pacific Ocean; on the southeast by Guatemala, Belize, and the Caribbean Sea; and on the east by the Gulf of...
. The Alamo Canal is also known as the Imperial Canal.
Planning and Construction
Historically, the Colorado River flowed to the Gulf of CaliforniaGulf of California
The Gulf of California is a body of water that separates the Baja California Peninsula from the Mexican mainland...
, however in times of flood 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
Salton Sink
The Salton Sink is a geographic sink in the Coachella and Imperial valleys of southeastern California. It is in the Colorado Desert subregion of the Sonoran Desert ecoregion...
area of the Colorado Desert
Colorado Desert
California's Colorado Desert is a part of the larger Sonoran Desert, which extends across southwest North America. The Colorado Desert region encompasses approximately , reaching from the Mexican border in the south to the higher-elevation Mojave Desert in the north and from the Colorado River in...
. 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
O. M. Wozencraft
Oliver M. Wozencraft 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 of America...
, 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
George Chaffey 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...
of the California Development Company
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 California...
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
Pilot Knob (Imperial County, California)
Pilot Knob is a peak in Imperial County, California.Pilot Knob is located southeast of Ogilby, It rises to an elevation of...
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 4 miles (6.4 km), 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
Algodones Dunes
The Algodones Dunes is a large 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 45 miles long by 6 miles wide and extends along a northwest-southeast line that correlates to...
.
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.
Failures
Between late 1904 and early 1907 a combination of severe flooding, excessive silting in the canal, and engineering attempts to both contain the flooding and allow reasonable flows of irrigation water to the newly settled Imperial Valley resulted in periods where the entirety of the Colorado River flowed into the Alamo River and New RiverNew River (Mexico – United States)
The New River flows north from near Cerro Prieto, through the city of Mexicali, Baja California, Mexico, into the United States through the city of Calexico, California towards the Salton Sea...
. These rivers drained to the endorheic Salton Sink.
The engineering attempts to allow a reasonable flow in the canal due to silting included the creation of three diversions without headgates; the first in the US, and then two in Mexico. The third diversion, created in October 1904, eventually channeled massive uncontrolled quantities of water into the canal during and after the subsequent seasonal floods of the Colorado River.
Multiple failed attempts were made to close the diversions and establish a controlled flow via headgates. On January 27, 1907 the flooding was finally stopped after substantial intervention by the Southern Pacific Company.
Legacy and Replacement
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 SeaSalton Sea
The Salton Sea is a shallow, saline, endorheic rift lake located directly on the San Andreas Fault, predominantly in California's Imperial Valley. The lake occupies the lowest elevations of the Salton Sink in the Colorado Desert of Imperial and Riverside counties in Southern California. Like Death...
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 judgement 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 judgements 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
Imperial Irrigation District
The Imperial Irrigation District was formed in 1911 under the California Irrigation District Act to acquire the properties of the bankrupt California Development Company and its Mexican subsidiary. The IID had acquired 13 mutual water companies, which had developed and operated distribution canals...
. 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
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, which was located mostly in Mexico...
was completed in 1940. By 1942 the All-American Canal was the sole canal providing Colorado River water to the Imperial Valley.