November 10, 1934: Arizona declares war against California at Parker Dam

by Julia Rosen
Wednesday, December 3, 2014

From above, tiny green irrigation circles draw a narrow buffer along the 2,300-kilometer course of the Colorado River like the brush strokes of a zoomed-in pointillist painting. These vibrant green dots stand out against the buff and ochre hues of the desert palette, a testament to the river’s life-giving waters. Less obvious are the 6.4 billion cubic meters of water that flow, or are pumped, more than 390 kilometers from the Colorado’s gorge through tunnels and canals, up and down hills, to the agricultural and population centers of Southern California each year, and the additional 3.4 billion cubic meters that gurgle toward Phoenix and central Arizona annually.

These highly contested waters originate from the Parker Dam, which spans the border between Arizona and California, corralling the Colorado River into the emerald expanse of Lake Havasu. In the long and complicated story of how the Colorado was tamed, the controversy over the Parker Dam — and the brief but astonishing war that erupted in November 1934 over its existence — embodies the abiding conflict over the river’s riches that continues to simmer today.

Tensions Build

Conflict over the Colorado River cleaves the southwest along several boundaries: the international boundary between the United States and Mexico, where the river meets the sea; the topographic transition between the upper states that contain the headwaters and the lower states that consume the majority of the river’s flow; the state line separating California and Arizona, the thirstiest states in the lower region, which is defined by the river’s southerly course; and even among California’s individual irrigation districts. The disagreement between California and Arizona stands out for its century-long legacy of mistrust and noncooperation fueled by Western water law, surging population growth and environmental variability.

The roots of the Parker Dam conflict stretch back to the beginning of modern water disputes in the West, formally governed by the Law of Prior Apportionment. This law states that the first to lay claim to river waters for any beneficial use will retain senior water rights forever onward, independent of land ownership. Decoupling water rights from land holdings makes sense in arid environments — otherwise a few individuals would possess sole control of a vital resource. However, the law also encourages a peculiar form of homesteading; California, with its booming cities and political clout, began staking claims to river water at the turn of the 20th century, threatening to leave other Colorado River states high and dry despite California’s distinction of being the only one of the seven Colorado River states not to contribute a single trickle to the Colorado’s flow.

Such fears motivated the states — Arizona, California, Colorado, Nevada, New Mexico, Utah and Wyoming— to form a compact in 1922 dividing the river’s waters evenly between the four upper states and the lower three states. Because the compact did not specify allotments for individual states within the two regions, Arizona remained in direct competition with California for water in the lower basin, and refused to ratify the compact. In 1928, the U.S. secretary of the interior prescribed allotments to the bickering lower basin states, granting California 59 percent, Arizona 37 percent and Nevada just 4 percent of the river’s flow. Arizona protested this distribution and continued to boycott the compact, even though it had no use for larger quantities at the time.

That same year, the Bureau of Reclamation approved the Boulder River Project, which became the Hoover Dam. In addition to providing flood control along the river, the new All-American Canal system would pull 4.7 billion cubic meters from the dam’s reservoir, Lake Mead, to irrigate California’s Imperial and Coachella valleys. The high tensions inspired by these events formed the backdrop against which the Parker Dam War erupted.

Arizona Goes to “War”

The Parker Dam was conceived and funded by the Metropolitan Water District of Southern California, although the U.S. Bureau of Reclamation managed the dam’s construction. As early as 1923, California planners had their eyes on Colorado River water, and began charting the course of an aqueduct to bring its water west. By 1931, they had mapped its route, and by 1933, had laid the first bricks of the Colorado River Aqueduct. In 1934, the Bureau of Reclamation commenced construction on the dam itself, to the great dissatisfaction of Arizona Gov. Benjamin Moeur."

Moeur, a doctor known for his great compassion as well as for his headstrong temperament, was fed up with what he saw as California’s aggressive seizure of Colorado River water rightfully belonging to Arizona. Encouraged by the state’s Attorney General, who declared construction on Arizona soil illegal, Moeur declared martial law on Nov. 10, 1934, and dispatched 100 National Guard troops from the 158th Infantry Regiment. The soldiers set up camp around the dam site, halting construction, and acquired two ferryboats owned by Nellie T. Bush, a famous steamboat captain and Arizona state legislator (as well as the temporary admiral of the “Arizona Navy”). The troops attempted to use the ferryboats to inspect the dam’s construction but got tangled in some cables and had to be rescued by enemy forces.

Although no shots were ever fired, the novelty of Arizona forming a navy and the strange nature of the conflict attracted a great deal of derision and media attention. Moeur’s extreme measures did, however, succeed in forcing the U.S. secretary of the interior to postpone dam construction, at least until the federal government officially reapproved the project and progress resumed in 1935. As it turned out, the Parker Dam War was only the opening battle in a long and bitter legal contest between the two states that would last more than half a century.

Despite numerous setbacks to the construction of Parker Dam, including having to dig through 70 meters of sediment to reach bedrock (three-quarters of the dam’s wall lies belowground), one short-lived war, a devastating fire and a labor strike, the dam was finally completed in 1938.

Half of the hydropower generated by Parker Dam's four generators, which came online in 1942, is used to pump water along the 390-kilometer-long Colorado River Aqueduct to Southern California. Credit: U.S. Bureau of Reclamation.

Even after the federal government overruled Moeur’s protests and the dam was completed, Arizona continued to fight for its right to Colorado River water. In 1944, still unable to use the full amount of its hard-fought apportionment because of sparse populations in the immediate vicinity of the river, the state recognized that it needed its own aqueduct to transport water to Phoenix and beyond, and finally agreed to ratify the 1922 compact in return for federal assistance with such a project.

The Central Arizona Project, the longest and most expensive aqueduct in U.S. history, originated at the Parker Dam and transported water southeastward. Congress approved the project in 1968 and it was finally completed in 1993. California protested the endeavor, however, since it depended on consuming the surplus left over by the unused allotments of other states. As late as 1997, the Colorado River still provided more than 60 percent of the water consumed in Southern California, constituting 20 percent more than the state’s allotment.

Compounding the issue was the problem that the 1922 compact was based on erroneously high estimates of river flow. Thus, states were promised between 15 and 25 percent more than the true long-term average flow, later deduced from tree-ring studies and other geologic proxies.

Over the better part of the last century, Arizona and California haggled over apportionments in a string of 10 Supreme Court cases. Even now, the issue is far from dead: In 1996, U.S. Secretary of the Interior Bruce Babbitt ordered California to reduce its use to only its allotted amount; in 2000, the states faced off in court yet again to tweak apportionments; and in 2008, Sen. John McCain, R-Ariz., proposed renegotiating the 1922 compact altogether.

Not Just a State Battle

The states have not been the only players in the debate over the Colorado’s waters. Native American tribes in the lower basin asserted their rights to water in the 1963 case of Arizona v. California, winning irrigation rights for their reservations, while other tribes continue to seek allotments today. Environmentalists continue to push for dam removal along the river, noting that more than 10 percent of the river’s waters evaporate every year from the vast surfaces of its reservoirs and that dams starve downstream ecosystems of vital sediment supplies. Mexico has also protested the precipitous decline in water quality delivered to its border over the last century, prompting the U.S. to build a desalination plant in 1973.

Now, the greatest threat to the fine balance of water use on the Colorado River comes from regional drought. Between 1998 and 2007, Lakes Mead and Powell lost more than half their volume, dispatching more water to users than they received. A recent study predicted the end of power generation due to low water levels at Hoover Dam in less than five years, and the potential for a dry reservoir in less than 10. The fate of Parker Dam, just 250 kilometers downstream, hinges on the balance of environmental, political and economic forces — but at least it is no stranger to conflict.

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