Compacts, court rulings regulate Colorado River
The Colorado River falls more than 12,000 feet as the waterway flows from the Rocky Mountains to the Gulf of California.
The river's 1,440 mile long drainage basin covers more than 244,000 square miles and passes through parts of seven states and Mexico.
Utah, Arizona, California, Colorado, Nevada, New Mexico and Wyoming are referred to as the Colorado River Basin states.
The drainage basin comprises about one-12th of the area of the continental United States.
But the Colorado ranks only sixth among the nation's rivers in volume of flow. The Colorado has an average annual flow in excess of 17.5 million acre-feet.
Demands on the Colorado are not limited to needs within the basin. In fact,more water is exported from the basin than any river in the U.S.
The Colorado provides municipal and industrial water for more than 24 million people residing in the major metropolitan areas of Los Angeles, Phoenix, Albuquerque, Las Vegas, Salt Lake City, Denver, San Diego and hundreds of communities in the seven states.
The river also provides irrigation water to about 2.0 million acres of land.
The Colorado has more than 60 million acre-feet of storage capacity, 4,000 megawatts of hydro-electric generating capacity, and provides more than 20 million visitor days of outdoor recreation annually.
The Colorado is frequently described as the most regulated river in the world.
In the 1800s and early 1900s, a sizable agricultural development emerged in California's Imperial Valley. Water was delivered from the Colorado River via a canal passing through Mexico. Mexico allowed Imperial Valley farmers to use the channel in exchange for a portion of the water in the river.
American farmers became unhappy with the Mexican government controlling the water supply and started to push for construction of a canal built entirely within the U.S.
Disastrous flooding occurred in California in 1905. The Colorado broke through a temporary diversion in the river bank and for two years, the entire flow poured into Imperial Valley.
The flooding destroyed homes and thousands of acres of agricultural land, filling a natural depression known as the Salton Sink and creating the Salton Sea.
As additional flooding occurred in 1910 and the Mexican Revolution started, pressure intensified to construct an all-American canal and build a flood control dam along with a storage reservoir on the lower mainstem Colorado River.
In addition, Los Angeles was interested in developing hydroelectric power. California realized construction of the projects would require the federal govern-ment's assistance, thus raising legal and political issues.
The remaining six basin states did not oppose structural control of the Colorado. But the remaining states were determined to resist proceeding with a development project in California until the six received satisfactory assurance of future use of the river water.
The solution appeared to be developing a compact between the basin states to apportion the river. Discussions started Jan. 26, 1922, with state and federal negotiators reaching an agreement regarding the provisions on Nov. 24 of the same year.
The compact split the river system into an upper basin consisting of Utah, Arizona, Colorado, New Mexico and Wyoming as well as a lower region comprised of Utah, Arizona, California, Nevada and New Mexico.
In addition, the agreement partitioned the rights to water between the lower and upper basins. The dividing line and measuring point was at Lee Ferry, located approximately 17 miles below the present Glen Canyon Dam.
The compact apportioned in perpetuity the exclusive, beneficial consumptive use of 7.5 million acre-feet of water annually from the Colorado.
The lower basin states also received the right to increase annual usage by one million acre-feet.
Compact negotiators were unsuccessful in the attempt to divide the water between individual states. But the compact reduced the upper basin concern that the faster growing lower basin states,particularly California, would monopolize the water.
The compact set aside the prior appropriation principle of "first in time, first in right " and allowed the basins to develop apportioned water without fear of losing it through non-use.
Arizona opposed including tributary water, specifically the Gila River, in the apportionment and refused to sign the compact.
The U.S. Congress subsequently did not ratify the agreement until the Boulder Canyon Project Act of 1928 allowed the compact to become law with the approval of six states and the enactment by California of a statute limiting its use of Colorado River water.
Arizona finally ratified the compact in 1944.
The 1922 compact was the first in a long process of negotiation, legislation and litigation. The process continues and the Colorado has been subjected to extensive negotiations and litigation.
In 1963, the U.S.Supreme Court decision in Arizona vs California confirmed the following lower basin apportionments:
California, 4.4 million acre-feet plus 50 percent of surplus.
Arizona , 2.8 million acre-feet plus 46 percent of surplus.
Nevada, 300,000 acre-feet plus 4 percent of surplus.
The 1908 Winters vs United States high court decision established the doctrine of Indian reserved water rights.
The ruling was reaffirmed by the Arizona vs California decision awarding water rights to five Indian reservations in the lower basin.
The court also ruled a tribe 's reserved rights must be charged against the apportionment of the state where the reservation is located.
Formal negotiations on an upper basin compact were initiated July 31, 1946, prompted by the desire of the states to continue water development put on hold in 1941 by wartime restrictions.
The states wanted to construct a major project, but federal funding was contingent on an upper basin compact.
On Oct. 11, 1948, the states entered into the upper basin compact to apportion allowable depletions. The four states were uncertain how much water would remain after delivering 7.5 million acre-feet per annum to the lower basin and how the Mexican Treaty obligation might affect the supply.
The states subsequently apportioned the remaining water as follows:
Utah, 23 percent.
New Mexico, 11.25 percent.
Wyoming, 14 percent.
Arizona , 50,000 acre-feet.
A major incongruity with the law of the river is the assumed quantity of water in the Colorado upon which the 1922 compact was negotiated, according to the Utah Department of Natural Resources.
The river's average annual flow from 1896 to 1921 at Lees Ferry was estimated at 17 million acre feet.
However, the states currently agree the compact was negotiated during a period of high water supply.
Recent estimates show the average annual flow to be 15 million acre-feet.
Subtracting the compact and treaty guaranteed annual apportionment and recognizing the impacts of sustained drought periods, the upper basin is left with an estimated dependable supply of about 6.0 million acre-feet.
As a result, Utah's allocated share is effectively reduced from 1.7 million acre-feet to approximately 1.4 million acre-feet.
The 1956 storage act authorized construction of Glen Canyon, Flaming Gorge, Navajo and Curecanti dams for river regulation.
The act authorized the U.S. Bureau of Reclamation to construct the central Utah project as one of the participating projects.
A1968 act authorized several projects in the upper and lower basins as well as developing long range operating criteria for the Colorado reservoir system.
The last 75 miles of the Colorado River are located within Mexico's boundaries.
A treaty signed in 1944 guarantees Mexico 1.5 million acre-feet to be increased in years of surplus to 1.7 million acre-feet and reduced in years of extraordinary drought in proportion to the reduction of consumptive uses in the U.S.
Since 1944,the U.S. has delivered at least the designated amount of water. The treaty did not mention water quality.
But a 1973 agreement between the U.S. and Mexico contains a provision guaranteeing that the deliveries at the northern international boundary will have an average annual salinity of no more than 115(plus or minus 30) parts per million more that the salinity of water arriving at Imperial Dam.
Since 1972, water delivered to Mexico has met the quality provisions.
In addition, quality has improved due to efforts of the federal, state and local governments as well as irrigation interests to control salinity.
An act was passed in 1974 authorizing federal funding to help control salinity in the Colorado.
The program authorizes federal agencies to cost share with state and local organizations for construction of projects to control salinity by decreasing the amount of salt entering the river.
In addition to the Carbon-Emery area, projects have been installed in Utah, Colorado, Wyoming, New Mexico and Nevada.
The majority have involved improvements in irrigation system efficiency.
In Utah, more than 100,000 acres of salinity control efficiency improvements have been installed in the Uintah Basin.
An additional 40,000 acres are being installed in the Price-San Rafael rivers area.
The downstream states of Arizona, California and Nevada as well as the federal government are the benefactors of improved water quality and provide up to 70 percent of the program's funding.
Approximately 5.2 million acre-feet of Colorado River water has been used annually by California in the past 20 years, representing 800,000 acre-feet more than the states compact allocation.
The guidelines allow California 15 years to implement conservation programs to reduce demand to comply with the compact allotment of 4.4 million acre-feet.
During the 15 year period, the remaining six states have agreed on criteria to assure California will be able to meet municipal and industrial needs. The criteria protects the six states against potential impacts of drought.
Portions of Utah lie within the upper and lower basins. In the upper basin, the Colorado enters Utah west of Grand Junction, but few diversions are made directly from the river in the area.
The largest use of the water is from the Duchesne River system in the Uintah Basin.
Lesser amounts are diverted from the Price, San Rafael, Dirty Devil, Escalante and San Juan river systems. Water is exported from the Uintah Basin to the Wasatch Front by CUP, the Provo River project,Strawberry project and several smaller diversions.
Most of Utah's lower basin usuage comes from the Virgin River and tributaries.
Agriculture is currently the largest consumer in the Kanab Creek and Virgin River drainages. But municipal and industrial demands are expected to increase threefold in the next 50 years, exceeding agricultural uses.
According to projections, Utah will have about 200,000 acre-feet of undeveloped Colorado River water available for future use in 2020.
Probably the last major water development project in Utah will be the CUP which will be funded by the federal government.
Additional private development of thermal power will likely occur in Emery and Uintah counties, pointed out the state's natural resources department. Municipal, industrial and agricultural water development will result as growth continues.
In the lower basin, diversions from Kanab Creek and Virgin River drainages will increase approximately 58,000 acre-feet annually by 2050, increasing depletions by about 36,000 acre-feet.
The population of the lower basin, one the fastest growing areas in the state, is expected to expand an average of 2.96 percent annually during the next 20 years. Utah's statewide annual rate of growth is predicted at 1.74 percent.
After starting to divide the water in the Colorado River about 80 years ago, the states and federal agencies have resolved many difficult problems through an informal process allowing flexibility and innovation.
Emerging issues continue to surface and resolving the matters informally requires the seven basin states to reach a consensus.
Participants must be willing to achieve solutions without unduly jeopardizing a single state's position.
The process is slow and difficult, but the solutions have united support, making implementation simpler and more efficient, concluded the Utah Department of Natural Resources.