High-flow releases at Glen Canyon Dam are meant to mimic the natural flooding of the Colorado River/NPS

As the National Park Service works to determine how the Glen Canyon Dam along the Colorado River operates for the next 20 years, a new study commissioned by the Glen Canyon Institute says halting hydropower generation at the site would have little impact on the western power grid.

The report, The Impact of the Loss of Electric Generation at Glen Canyon Dam, was released last month and prepared by Power Consulting. It summarizes that “if Glen Canyon Dam stopped generating hydropower, it would have a negligible impact on the western power grid, would raise electric rates by an average of 8 cents per month for residential customers of hydropower, and could save tens of millions of dollars each year in taxpayer subsidies and water lost to system inefficiencies.”

The dam, completed 50 years ago, is a key cog in a complex system to allocate water to seven states in the Colorado River basin but has been lamented by conservationists since its approval. To allocate water and electricity, the reservoir, Lake Powell, flooded what the Glen Canyon Institute describes as “a wonderland of spires, gorges, cliffs, and grottoes.” The lake stores water that is drawn on in times of drought, upstream from Hoover Dam and its reservoir, Lake Mead. Secondarily, the Glen Canyon Dam annually produces around 5 billion kilowatt-hours of hydroelectric power, which is distributed by the Western Area Power Administration.

“Our study investigated the claim by water and power managers that the loss of hydropower generation at Glen Canyon Dam would have catastrophic impacts on the customers that currently get at least some of their electricity from the dam,” said Dr. Thomas Power, principal at Power Consulting and a research professor and professor emeritus in the University of Montana Department of Economics. “Based on an exhaustive review of the data, we found this claim to be largely inaccurate. A small subset of customers would experience a significant rate increase, but for the vast majority, the increase would be minuscule.”

The key findings of the report:

• The average annual value of Glen Canyon Dam’s electric energy represents less than one half of 1 percent of the sales value from electric generation in the western grid, and that the grid could readily absorb the loss of hydropower from the dam.
• The total impacts would be an increase of $16.31 million in electricity costs for consumers of Glen Canyon Dam power, but because they would be spread among 3.2 million customers, the individual impacts would be small in the vast majority of cases.
• The average annual value of the Glen Canyon Dam electric energy is $153.3 million. This value is less than one half of one percent of the close to $31 billion in sales value from electric generation in the Western Electricity Coordinating Council.
• Average yearly cost increases would be $.08 per month for residential customers, $.59 per month for commercial customers, and $6.16 per month for industrial customers of Glen Canyon Dam electricity.
• A discontinuation of Glen Canyon Dam operations could have offsetting benefits of approximately $74.8 million annually, including savings of $34.9 million in management costs and potential earnings of as much as $39.8 million annually due to increased hydropower at Hoover Dam and conservation of water that would have otherwise seeped into the banks of Lake Powell.

Earlier this year, the National Park Service took comments on a draft environmental impact statement on how to operate the dam for the next 20 years, and none of the alternatives called for removing the dam. At 710 feet, the Glen Canyon Dam is the second-tallest concrete-arch dam in the United States (just 16 feet short of Hoover Dam). Although Lake Powell was at 3,620 feet (80 feet from full pool) in June, the level was expected to drop going into fall and winter. In recent years, parts of Glen Canyon National Recreation Area have been closed due to low water levels, which are expected to worsen.

Daniel Beard, a former commissioner of the U.S. Bureau of Reclamation, wrote a book on why the Glen Canyon Dam should be decommissioned. In Deadbeat Dams: Why We Should Abolish the U.S. Bureau of Reclamation and Tear Down Glen Canyon Dam, published last year, Beard argues that “the current state of affairs at Glen Canyon Dam leads me to conclude that we should remove Glen Canyon Dam, drain Lake Powell, and allow the Colorado River to fill Lake Mead behind Hoover Dam.”

The Glen Canyon Institute, a nonprofit dedicated to restoring a free-flowing river through Glen Canyon, agrees that Lake Mead should be filled first, with Lake Powell as a backup.

“This study debunks another major rationale for the argument that we need to maintain the status quo at Glen Canyon Dam and Lake Powell to ensure the integrity of the Colorado River system,” said Eric Balken, executive director of Glen Canyon Institute. “The Power team’s analysis shows that even if Lake Powell were completely drained, the loss of hydropower would have a minimal impact on the vast majority of consumers of this power. For the small number of consumers who would experience a greater impact, such as Native American utilities, we believe there are viable strategies for offsetting any rate increase.”

The research was reviewed by an independent panel of economists: David Marcus, Gail Blattenberger, and Spencer Phillips.