Are Colorado River Water Supplies Being Wasted?
Answering NRDC’s Concerns about the Colorado River—Part 1 of 3
The short answer is no. There are legal and contractual measures in place to prevent unreasonable use.
The Colorado River is suffering because of overallocation and persistent drought, but that is not stopping a group of environmental organizations from pushing for a federal definition and enforcement mechanism to ensure that water of the Colorado River is not wasted.
On May 6, 2025, an environmental coalition submitted a petition to the U.S. Bureau of Reclamation requesting that the agency “utilize its legal authority to stop waste of Colorado River water” in the Lower Basin. The groups state that the river is imperiled by over-allocation and climate change, and they call for swift action to “reform the use of Colorado River water.”
The Natural Resources Defense Council (“NRDC”) took the lead as signer of the petition and are supported by several Waterkeepers and local organizations, including Los Angeles Waterkeeper, California Coastkeeper Alliance, Russian Riverkeeper, Alamosa Riverkeeper, San Diego Coastkeeper, Inland Empire Waterkeeper, Orange County Coastkeeper, Utah Rivers Council, and Great Salt Lake Waterkeeper. The petition was penned by students of the UCLA Frank G. Wells Environmental Law Clinic.
The petition is centered on an assertion that Reclamation is not upholding its legal obligation to make sure that water deliveries in the Lower Basin States are not being used in unreasonable or wasteful manners.
“This petition lays out how—under existing law, and by its own admission in federal court—the Bureau has a mandate to ensure that the water it delivers to California, Arizona, and Nevada is not squandered on unreasonable uses,” said Cara Horowitz, director of the Frank G. Wells Environmental Law Clinic at UCLA School of Law.
The petitioners are requesting that Reclamation undertake three specific actions:
Undertake a process with stakeholder input to define the phrase “reasonably required for beneficial use;”
Develop a robust, consistent, and transparent process for determining whether Lower Basin water users are adequately avoiding wasteful, unreasonable uses of water;
Require and perform periodic reviews of Lower Basin water users to ensure that all water deliveries are, in fact, being used reasonably.
While appearing to be simple procedural actions, these requests take aim at a foundational concept of water rights management—reasonable and beneficial use.
While “reasonable and beneficial use” is often defined by what it is not, it is well understood throughout the water industry. It is addressed in state constitutions and statutes throughout the West and is a key concept of the Quantification Settlement Agreement (“QSA”).
The QSA was signed in 2003 with a primary purpose to bring California’s water use from the Colorado River within its 4.4 MAF annual allocation and to facilitate certain water transfers. According to a recent public outreach document by the San Diego County Water Authority, it was also designed to promote efficiency.
In addition to pushing for a lengthy federal process to define beneficial use and develop new enforcement measures, the coalition appears to have an underlying condemnation of priority water rights administration—the long-held “first in time, first in right” principle that is used throughout the West to determine the order in which curtailments are implemented—and a sense of urgency that suggests that they believe no action is being taken to improve management of Colorado River. These issues will be addressed in parts 2 and 3 of this series.