History of Early Major Diversions
on the Lower Colorado River
COLORADO RIVER INDIAN RESERVATION-AZ
First diversion was made in July 1870 by a canal with gravity heading from which diversion could be made only during high stages of the river. Minor diversions were made until about 1898 when a 40 horsepower engine and 15 inch centrifugal pump were installed. This plant was enlarged in 1912 and in 1918. On June 28, 1942, all pumping ceased with diversion being by gravity at Headgate Rock Dam.
PALO VERDE IRRIGATION DISTRICT-CA
The first water used for irrigation was diverted about 1879. The Bureau of Reclamation built an emergency rock weir in 1945 to raise the riverbed due to loss of sediments from closure of Hoover Dam. Palo Verde Diversion Dam was completed in 1957.
IMPERIAL IRRIGATION DISTRICT-CA
First diversion from the Alamo Canal for use in Imperial Valley was on May 14, 1901. Diversions from the All-American Canal began in 1940.
WELLTON-MOHAWK IRRIGATION DISTRICT-AZ
Diversions from the Gila River began in the late 1800's. Due to extended droughts and damaging floods, groundwater pumping began in 1906 using a wood-burning generation plant. By 1934, salt buildup led to abandoning of many farms, with reprieves by the spring flood of 1941 and the cloudburst of 1951. Diversions from the Colorado River began in January 1952. This led to a high water table and saline buildup that was pumped as drainage to the Gila River. The main conveyance drainage channel began operation in 1961.
VALLEY DIVISION, YUMA PROJECT (Yuma County Water Users Assn)-AZ
Diversions prior to completion of Laguna Dam in 1909 were made by pumping plants. Water was first delivered through the Colorado River siphon on the Yuma Main Canal diversion at Laguna Dam in June 1912. Delivery of water to Mexico at the southern land boundary began in 1919 from the East Main Canal and the pumped Main Drain.
RESERVATION DIVISION, YUMA PROJECT-CA
Water was first diverted by the Yuma Canal in 1910 at Laguna Dam. In June 1948 deliveries ceased from Laguna Dam when all deliveries were made from the All-American Canal.
NORTH GILA VALLEY, GILA PROJECT-AZ
Diversion began about 1912. Diversions from the Gila Gravity Main Canal began December 16, 1954.
UNIT B (YUMA AUXILIARY PROJECT)-AZ
Water was first pumped to the project in 1922 from the Yuma Main Canal below the Colorado River siphon. After July 6, 1953, delivery was made from delivery of water to Yuma Mesa from the Gila Gravity Main Canal.
SOUTHERN NEVADA DIVERSIONS FROM LAKE MEAD-NV
Pumping records to Boulder City began in April 1934 from a plant inside Hoover Dam. In April 1942 water was diverted from intakes on Saddle Island on Lake Mead for war effort plants in Henderson, Nevada. With declining groundwater levels, large diversions for the Las Vegas Valley began in January 1984 through the Southern Nevada Water Project diversion at Saddle Island.
METROPOLITAN WATER DISTRICT-CA
Pumping began in January 1939, with the filling of Lake Havasu at Parker Dam.
YUMA MESA IRRIGATION AND DRAINAGE DISTRICT-AZ
Diversions began in November 1943.
COACHELLA VALLEY WATER DISTRICT-CA
First diversion in the Coachella Canal branch of the All-American Canal was in 1944.
YUMA IRRIGATION DISTRICT (GILA PROJECT, WARREN ACT CONTRACTS)-AZ
Diversion began in 1944 to Warren Act contractors which were included in the district in 1966.
CENTRAL ARIZONA PROJECT-AZ
Groundbreaking for the project began in 1973. First diversion from Lake Havasu began in 1985. The water supply system (stage 1) was completed in December 1993.
Updated: November 2004