Aug. 15, 2022

UArizona water experts available to discuss Colorado River cuts

TUCSON, Ariz. – Water levels in Lake Mead and Lake Powell continue to dip to historic lows as the Aug. 16 deadline approaches for the seven Colorado River Basin states of Arizona, California, Nevada, New Mexico, Utah, Colorado and Wyoming to announce dramatic water usage cuts.

The deadline for the western states was set in June during a federal hearing before the U.S. Senate Committee on Energy and Natural Resources. The states must announce plans to conserve between 2 and 4 million acre-feet of water in the next year, or the Bureau of Reclamation will impose cuts itself.

The total water allocation budget for the Colorado River is 16.5 million acre-feet per year, with 15 million acre-feet per year allotted to the U.S. and 1.5 million acre-feet to Mexico.

"In the past two decades, the average annual flow of the Colorado River from 2000 to 2018 has been approximately 12.4 million acre-feet, which is 16% lower than the 1906 to 2017 average of 14.8 million acre-feet per year," said Jeffrey Silvertooth, a University of Arizona professor of environmental science with expertise in water usage as it relates to agriculture.

This is why the bureau is pushing for up to 4 million acre-feet of cuts, he said.

The Colorado River supports approximately 40 million people in seven U.S. states and two states in Mexico, including 30 tribal nations and 5 million to 6 million acres of irrigated farmland. All of these entities depend on the Colorado River for water. Yet, decades of drought and over-allocation has dramatically depleted reservoirs.

"The situation on the Colorado River continues to tighten, for all parties," Silvertooth said.

The following UArizona experts are available to discuss the cuts.

Jeffrey Silvertooth is a professor in the Department of Environmental Science and a Cooperative Extension specialist in agronomy – the science of soil management and crop production. His research focuses on the development of crop production management strategies that optimize the soil-plant system. An important part of his work is irrigation management for optimum efficiency in desert agricultural systems. He has worked extensively on agricultural water use across the state and in irrigation districts using Colorado River water.
520-621-7616
silver@ag.arizona.edu

Sharon B. Megdal is director of the Water Resources Research Center, a Cooperative Extension center and research unit in the College of Agriculture and Life Sciences. She served on the elected Central Arizona Project Board of Directors for 12 years and can discuss Colorado River management from a regional perspective. Her research focuses on water management, policy and governance in water-scarce regions; groundwater recharge; and groundwater conditions along the U.S-Mexico border.
520-621-9591
smegdal@arizona.edu

Kathy Jacobs, director of the Center for Climate Adaptation Science and Solutions, has expertise in water policy, the use of climate information for water management, climate change adaptation and drought planning. Jacobs was a groundwater manager for the state of Arizona for 23 years and was director of the Tucson Active Management Area for 15 years. She helped design conservation, recharge and assured water supply rules for Arizona. Jacobs recently led the Colorado River Conversations Project, which explored the impacts of extreme climate and weather events and identified collaborative solutions. She recently published a paper on extreme events in the Colorado River Basin and wrote a chapter in the upcoming book on the Colorado Compact.
520-405-7395
jacobsk@arizona.edu

Robert Glennon is a Regents Professor Emeritus at the College of Law and is one of the nation's preeminent experts on water policy and law. He advocates for a variety of reforms, including using price signals to stimulate water conservation and market forces to bring about a reallocation of water. Glennon is author of the highly acclaimed "Unquenchable: America's Water Crisis and What to Do About It." He serves as an adviser to governments, corporations, think tanks, law firms and nongovernmental organizations looking to solve serious challenges around water sustainability and planning.
520-621-1614 (NOTE: He is currently on the East Coast, so he requests no late calls)
glennon@law.arizona.edu

Jessica Tierney is a professor and one of about 20 U.S. authors on the IPCC Working Group 1 contribution to the Sixth Assessment Report, which provides the latest assessment of scientific knowledge about the warming of the planet. As a paleoclimatologist, she can also speak to projections for future warming and its impacts on the climate system. She can provide big picture context for how the changing climate might impact water availability.
jesst@arizona.edu

Andrea Achilli is an associate professor of chemical and environmental engineering. His main fields of research are membrane processes for desalination, as well as water reuse and energy recovery from water and wastewater. He can also offer perspective on other technologies designed to provide additional water resources from unconventional sources.
520-621-6044
achilli@arizona.edu

Michael Crimmins is a professor in the Department of Environmental Science and a Cooperative Extension climate specialist. His research supports resource management across multiple sectors including rangelands, forests/wildfire and water resources as well as informing policy and decision makers. He also serves as a drought monitoring expert on the Arizona Governor's Drought Task Force and has worked with counties across Arizona to implement drought preparedness and impact monitoring plans.
520-626-4244
crimmins@arizona.edu

# # #

Media contact:
Mikayla Mace Kelley
University Communications
520-621-1878
mikaylamace@arizona.edu

The University of Arizona, a land-grant university with two independently accredited medical schools, is one of the nation's top 50 public universities, according to U.S. News & World Report. Established in 1885, the university is widely recognized as a student-centric university and has been designated as a Hispanic Serving Institution by the U.S. Department of Education. The university ranked in the top 20 in 2020 in research expenditures among all public universities, according to the National Science Foundation, and is a leading Research 1 institution with $761 million in annual research expenditures. The university advances the frontiers of interdisciplinary scholarship and entrepreneurial partnerships as a member of the Association of American Universities, the 66 leading public and private research universities in the U.S. It benefits the state with an estimated economic impact of $4.1 billion annually. For the latest on the University of Arizona response to the novel coronavirus, visit the university's COVID-19 webpage.