The All-American Canal is the Imperial Valley's lifeline from the Colorado River. Approximately 3.1 million acre-feet of Colorado River water, less water transfer obligations, is delivered annually through the All-American Canal to nine cities and 500,000 acres of agricultural lands throughout the Imperial Valley.
Considered an engineering marvel, even by today's standards, the 80-mile gravity-flow All-American Canal begins at Imperial Dam on the Colorado River about 20 miles northeast of Yuma, Arizona. Dropping a total of 175 feet between Imperial Dam and the Westside Main Canal, the All-American Canal extends south and then west, following the Mexican/American border much of the way.
Crossing 14 miles of sand dunes on the east side of the Imperial Valley, the All-American Canal ends in the southwest corner of IID's delivery area. In 2009, the district completed a canal lining project that resulted in the concrete lining of 23 miles of the canal.
Survival and development in the Imperial Valley has always been dependent on water and its availability. The quest to bring water from the Colorado River to irrigate land in Imperial Valley began in the 1850s. However, it was not until 1901 that the California Development Company contracted to build a canal (the Alamo Canal) to deliver water by gravity flow from the river to the southern end of the valley. The Alamo Canal's diversion point was a short distance north of the Mexican border near Pilot and most of its length ran through Mexico before it re-crossed the border into the Imperial Valley.
IID was formed in 1911 under a state charter and acquired certain rights of the California Development Company and its Mexican subsidiary. Because its main canal and levees were located in Mexico, giving Imperial Valley little security in its water supply or against flooding, the IID realized the need for an "All-American Canal" north of the international border.
The concept of an all American canal was not new. In 1912, Mark Rose, a pioneer farmer, went to Washington, D. C., seeking funding for a canal on his land in Imperial Valley's East Mesa. In 1917, IID's chief counsel, Phil Swing (who later became a U.S. Congressman), successfully negotiated an agreement between the United States Bureau of Reclamation (USBR) and the IID to investigate the Imperial Valley's need for an all American canal. The early pioneers' efforts paid off and, in 1928, the Boulder Canyon Project Act authorized the construction of the All-American Canal, Hoover Dam and Imperial Dam. The All-American Canal was constructed by the USBR during the 1930s and, in 1940, the first water was delivered to Imperial Valley. In 1942, the All-American Canal became the sole water source for Imperial Valley residents and area farmlands.
Through this gravity-flow canal, Colorado River water is conveyed to the head of the IID's system at Drop No. 1. Several main canals branch off the All-American: the East Highline, Central Main and Westside Main canals. Service to Imperial Valley is provided from these three main canals or from the tributary lateral canals that they supply. In total, IID controls and maintains 1,675 miles of irrigation canals in the Imperial Valley. In addition, IID's distribution system also includes ten reservoirs, with a total storage capacity of more than 3,300 acre-feet.
All-American Canal Specifications
|Overall length||80 miles|
|Total Drop||175 feet|
|From Imperial Dam to
Siphon Drop Power Plant
|From Siphon Drop Power Plant
to Pilot Knob
|From Pilot Knob
to Drop No. 1
Yuma Project: Diverts 2,000 cfs through Siphon Drop Power Plant and other turnouts on the canal upstream from Siphon Drop.
Coachella Main Canal: Diverts 2,500 cfs at Drop No. 1, 20 miles west of Yuma.
The All-American Canal was built by the USBR. The IID made semi-annual payments, as part of a 50-year contract ending in 1994, to the U.S. Government to repay the construction loan on the All-American Canal.
|Construction/soil||Unlined in mostly shifting silt and sand.|
The All-American Canal trashrack and headgates are located adjacent to the California abutment of Imperial Dam. Three desilting basins (design capacity 4,000 cfs each) remove the sediment from the river's water before it passes to the All-American Canal. The sediment is returned to the river by means of six sludge return pipes that deposit the sediment into the California Sluiceway.
The passage of the Boulder Canyon Project Act in 1928 served as a springboard for hydroelectric power in the valley. Part of the act required the secretary of the interior to obtain local guarantees for repayment of the construction costs for the All-American Canal, among other projects. The IID recognized that the people of the Imperial Valley could repay their share of the construction loans as long as they were given the right to use the power generated on the All-American Canal.
The first hydroelectric plants on the All-American Canal were completed at Drops 3 and 4 in 1941 and a Drop 2 hydropower facility was installed in 1953. The Pilot Knob Hydro Plant was built on a bypass channel between the All-American Canal and the Colorado River, and went into operation in 1957. The Drop 5 installation was completed in 1982 and the Drop 1 and East Highline Turnout hydro plants were commissioned in 1984.
AAC Storage Reservoirs
The Off Line Storage Reservoir was constructed as part of the All American Canal Lining Project. The OLS replaced most of the system storage lost by the lining of the All American Canal. The original All American Canal channel between AAC Drop 1 and AAC Drop 2 was lined and converted into a 1,000 Acre Foot Reservoir. The OLS began service in 2009.
|OFF LINE STORAGE RESERVOIR|
|Overall length||4.5 Miles|
|Maximum Depth||13.6 feet|
|Inlet/Outlet Capacity||400 CFS|
|Capacity||1,000 Acre Feet|
The Warren H. Brock Reservoir is a Bureau of Reclamation Colorado River Storage facility that is located above AAC Drop 2. The reservoir is controlled by IID’s Water Dispatching Unit under the direction of the Yuma Area Office (USBR). The Brock Reservoir was constructed to capture excess water that would have flowed to Mexico unordered. The Brock Reservoir has two 4,000 acre-feet storage cells. The Brock Reservoir began service in 2010.
|WARRIN H. BROCK RESERVOIR|
|Surface Area||485 Acres|
|Maximum Depth||22 Feet|
|Inlet/Outlet Capacity||1,800 CFS|
|Cell 1 Storage Capacity||4,000 Acre Feet|
|Cell 2 Storage Capacity||4,000 Acre Feet|
|Total Capacity||8,000 Acre Feet|
The All-American Canal, All-American Canal Works, Imperial Dam and Gila Headworks are operated and maintained by the IID, with costs shared by the USBR, Coachella Valley Water District, Yuma County Water Users and other water users.