How the Colorado River Compact defines water use in 7 western states
By Amy Ostdiek | Rio Grande Basin Roundtable
This year marks the 100th anniversary of the Colorado River Compact. This commemoration provides an opportunity to reflect on the durability of the compact and the equities it guarantees. Meanwhile, the current state of the Colorado River system provides a sobering reminder that current operations must be better aligned with hydrologic realities.
The Colorado River Compact defines the Upper Basin (Colorado, New Mexico, Utah, and Wyoming) and Lower Basin (Arizona, California, and Nevada) and provides equal apportionments of 7.5 million acre feet to each the Upper Basin and Lower Basin in perpetuity. The compact provides the foundation for management of the Colorado River, upon which a host of other laws and agreements guide and govern current operations.
Some of these agreements further define water apportionments by state. For example, the 1948 Upper Colorado River Basin Compact apportioned the Upper Division States’ 7.5 million acre-foot apportionment among the four Upper Division States, based on percentages of water available for use. The Upper Basin Compact also created the Upper Colorado River Commission (UCRC), which serves as a coordinating body for the Upper Division States.
The Lower Division States’ 7.5 million acre-foot apportionment was divvied up through federal legislation and a U.S. Supreme Court Decree, rather than an agreement. This resulted in the secretary of interior becoming water master in the Lower Basin, thereby creating a greater degree of federal involvement and oversight in the Lower Basin than in the Upper Basin.
This article was brought to you by the Rio Grande Basin Roundtable. The roundtable meets the second Tuesday of the month. If we are in-person, we are meeting at the Rio Grande Water Conservation District, 8805 Independence Way, Alamosa, CO 81101. Due to Covid restrictions we are also offering a Zoom option. We welcome your attendance but encourage checking the Roundtable website at www.RGBRT.org prior to the meeting to see if an in-person option is available.
IMPORTANTLY, the Colorado River Compact specifically leaves in place the states’ control over water within their respective boundaries. In other words, the compact does not dictate how water rights are administered in Colorado. The State Engineer’s Office maintains exclusive authority over the administration and management of Colorado’s water resources. Moreover, the Upper Division States have never failed to meet compact obligations.
In fact, the Upper Division States regularly use 3 to 4 million acre-feet less than their compact apportionment, due in part to the strict administration of water rights and the lack of available water supplies. Because most Upper Division States’ water users do not have a large reservoir upstream of their use, the Upper Division States’ uses rise and fall with availability of water supply in a given year. In dry years, this regularly results in painful cuts for Colorado water users. In 2021, the Ute Mountain Ute Tribe received only 10 percent of its apportionment and fallowed more than 6,000 acres as a result.
Shortages like those of the Ute Mountain Ute Tribe are in sharp contrast to the certainty and consistent deliveries provided by Lakes Powell and Mead to the Lower Division States, which have not been reduced despite very dry conditions. This has allowed the Lower Basin States to consistently use more than their Compact apportionment.
The silver lining of this reality is Colorado’s resilient water users. Colorado lives within our means on an annual basis, and the current crisis has forced our water users to be resilient and innovative in light of the unprecedented challenges imposed by climate change and prolonged drought. While the solutions available across the Colorado River Basin vary based on local challenges and management structures, the most impactful solution for the entire Colorado River Basin is to live within the means of what the River provides.