November 11, 2020

Allocating the Navajo Generating Station’s Water: A Rare Opportunity on the Colorado River

Gregor MacGregor

The Bureau of Reclamation recently announced another poor water season in the Colorado River Basin, with runoff coming in at only 55 percent of the average. Critical shortages in Lakes Mead and Powell––the two major reservoirs serving 30 million people from Wyoming to California–– now have a 77 percent chance of occurring by 2025. With the growing impacts of climate change, these water shortages are not a surprise. Between 2015 and 2018, the average annual flow of the Colorado River fell by 20 percent, and some climate scientists predict that ongoing climate change will drive a further flow reduction of 50 percent by the year 2100. This lack of water poses a threat to seven U.S. states, Mexico, and several tribal governments, all of which depend on the Colorado River for drinking water and agriculture. 

Against this backdrop of a looming regional water shortage, tribal governments throughout the Southwest are particularly impacted, especially as they attempt to contain COVID-19 in some of the least water-secure areas in the country. On the Navajo Nation nearly 40 percent of households lack running water, necessitating additional trips across rough roads to collect water for hand washing and sanitizing because of the coronavirus. Increasing aridity and a lack of essential services are two other ongoing threats to the health and development of the Nation, but the solution to both may come from an unlikely source situated near the banks of Lake Powell––the Navajo Generating Station (NGS).

Colorado River

Colorado River

Charles Wilkinson’s “Fire on the Plateau” (1999)

The Rise and Fall of the NGS

In November of 2019, the NGS outside of Page, Arizona, closed after nearly 50 years of operation. New regulations increased the cost of retrofitting the plant and lower prices on the electricity market, driven down by natural gas production, made the NGS a liability for its utility owners. The Central Arizona Project (CAP), a major aqueduct and utility owner of the NGS, which pumps more than 500 billion gallons of water uphill from Lake Havasu (on the Colorado River) to metropolitan Arizona, stood to save $38.5 million per year by shuttering the plant and purchasing natural-gas fueled power on the open market instead. This fundamental shift in the economics of power production deterred several utilities, and the Navajo Nation, from taking over the plant.

Although a blow to the local economy and tribal governments, the closure of the NGS leaves behind the rich potential of 34,100 acre-feet––more than 11 billion gallons––of water for other uses each year. Arizona is entitled to use this portion of the Colorado River’s flow above Glenn Canyon Dam, an area of the state that is almost entirely composed of the Navajo Nation. Therefore this is water that the Navajo have a legal and moral right to use.

The Navajo Nation’s Legal Claim

Understanding the Nation’s claim is complex and requires contextualizing those acre-feet of water within the turmoil and growth of the American Southwest. The NGS was constructed during the mid-century shift in federal American Indian policy, a concerted effort to urbanize and industrialize the Southwest, and the growing political power of a burgeoning environmental movement as seven states and two nations tried to allocate water in the desert. It is a story of expeditions to golden cities, deployment of the Arizona “Navy,” duplicitous backdoor deals, and interstate diplomacy. At almost every step of the way, native communities and their water rights were either ignored or sidelined when the question of allocation arose.

The allocation of water on the Colorado River began in the early twentieth century under the Colorado River Compact. The Compact and ensuing laws, lawsuits, and treaties separate the governments relying on the river into three groups. Together, Wyoming, Colorado, Utah, and New Mexico form the Upper Basin States. These states, and the almost exclusively tribal northeastern slice of Arizona, are entitled to use 7.5 million acre-feet (maf) of the Colorado River’s flow. This leaves the Lower Basin states of Nevada, California, and Arizona a maximum allotment of 8.5 maf of Colorado River water, and a treaty with Mexico promised our southern neighbor 1.5 maf. Although the basic framework of the Colorado River Compact took shape in 1922, it would take nearly 40 years to settle disputes between Arizona, California, and the federal government.

In 1944 the Upper Basin States convened to split their 7.5 maf portion of the Colorado River. As with the Colorado River Compact, there were no tribal representatives present, and no tribal assent was given when the Upper Basin States divided the water among themselves. Importantly, the Upper Basin Compact allotted 50,000 acre-feet of water to the area of Arizona above Glen Canyon Dam. Although the Navajo were not represented at the negotiating table, the Nation later made several agreements pursuant to the Upper Basin Compact’s terms, which made the construction of the NGS possible.

In the 1960s the Navajo moved to formally participate in the allocation of Colorado River water despite being excluded from legal forums for decades. In 1966 the Navajo Tribal Council explicitly laid claim to the 50,000 acre-feet of water allotted to northeastern Arizona based on the geographic allocation of the Upper Basin Compact. A series of resolutions memorialized the stance of the Secretary of the Interior and the governor of Arizona that the water could and should be used for the Navajo Reservation. By 1968 the Nation had resolved to dedicate 34,100 acre-feet of water to the NGS for 50 years, provided that the water would be returned to the Navajo for their exclusive use and benefit. The federal government, the state of Arizona, and the Navajo Nation clearly recognized the Navajo right to use this water based on the terms of the Upper Basin Compact when the NGS was built. Now is the time to return that water to the Navajo Nation under the terms of the compact, resolutions, and agreements that quenched Arizona’s thirst.

The Nation’s Moral Claim

The Navajo right is also a moral one. In the 1960s, the Bureau of Reclamation planned to build dams inside the Grand Canyon to power the Central Arizona Project. The massive aqueduct was the only way Arizona could use its share of lower basin Colorado River water. Despite the momentum behind the project, environmental groups led by David Brower of the Sierra Club managed to rally public opinion against the dams. In order to preserve the Grand Canyon and pump Colorado River water to Phoenix and Tucson, the two sides compromised by authorizing the construction of Glen Canyon Dam, the impoundment of Lake Powell, and the construction of the NGS. Through the early twenty-first century, the coal plant provided power and funding to bring water to Phoenix and Tucson, allowing those cities and their environs to expand in population, economic development, and agriculture. Although the Navajo did realize some profits from leases, they lost the opportunity to develop using that same electricity and water. More importantly, while metropolitan centers in Arizona benefited from the NGS, tribal communities labored under the twin costs of lost opportunity and hazardous pollution. After bearing the burdens of development, it is time for the Navajo Nation to benefit from the opportunity.

Future Opportunities

The closure of the NGS makes it possible to finally recognize the Navajo claim to the NGS’s allocation of Colorado River water. Upholding that right would free water for use in alternative industries to replace the jobs and revenues lost after the NGS shuttered and would improve water security for the 40 percent of households on the reservation that lack running water. While the NGS water is not a panacea for all difficulties facing the Navajo Nation, it may serve as a foundation for quality of life improvements and economic development in the face of an uncertain future.

For the full account, and an epilogue examining the potential for renewable energy project finance at the NGS site, visit the Colorado Natural Resources, Energy & Environmental Law Review website at

Gregor MacGregor


Gregor MacGregor practices water law in Boulder, Colorado, at Moses, Wittemyer, Harrison & Woodruff P.C. Prior to joining the firm, MacGregor finished his Army career by serving as the Water Rights Advisor to Fort Carson. During law school he served as an editor on the Colorado Natural Resources, Energy & Environmental Law Review, competed in the National Energy Moot Court Competition, and served as the student director of the pro bono Acequia Assistance Project. In his free time, MacGregor enjoys winter sports with his two daughters, homebrewing, and buying too many books.