Another Perspective On The Glen Canyon Dam
November 16, 2020
The Glen Canyon Institute is an advocacy group opposed to the dam. I took the following information from its website.
Glen Canyon is one of America’s — and the world’s — greatest natural wonders. John Wesley Powell, who named Glen Canyon during his 1869 survey, described it as a “land of beauty and glory.” Edward Abbey wrote that Glen Canyon was “a portion of earth’s original paradise.” Wallace Stegner judged the Glen to be “potentially a superb national park.”
In 1963, the diversion tunnels of Glen Canyon Dam were screwed shut causing the waters of the Colorado River to back up 186 miles through Glen Canyon forming Lake Powell. Built for political purposes, the dam was originally meant to provide a sustainable water supply to the arid Southwest, but has since undermined that very objective and has caused massive collateral damage across the Colorado River Basin. Before the dam, Glen Canyon was a wonderland of gorges, spires, cliffs, and grottoes; the biological heart of the Colorado River, with more than 79 species of plants, 189 species of birds, and 34 species of mammals; and a cultural treasure, with more than 3,000 ancient ruins.
After the dam, Glen Canyon became known as “the place no one knew” and America’s “lost national park.” Legendary conservationist David Brower lamented, “Glen Canyon died in 1963…. Neither you nor I, nor anyone else, knew it well enough to insist that at all costs it should endure. When we began to find out it was too late.”
Folly is always folly — yet this one is rare in that the mistake of damming Glen Canyon became clear within the lifetimes of the people responsible. But it’s also rare in that, here, we may really get a second chance. If the Glen Canyon Institute and others have their way, we’ll bypass this dam, fill Lake Mead, and designate Glen Canyon a national park…. When that happens, the drained Lake Powell and the resurrected Glen Canyon will be emblematic not of our folly but of the graciousness with which nature is still willing to meet our adolescent species halfway. It will be a monument to the possibility that we haven’t totally screwed up the planet forever, that we might still be able to back off a little and make our peace with the rest of Creation.
— Bill McKibben, Forward, Resurrection: Glen Canyon and a New Vision for the American West (2009)
Through its creation, Lake Powell and Glen Canyon Dam effectively destroyed the unique ecosystem of Glen and Grand Canyon, with negative consequences reaching all the way to the Colorado Delta downstream. Designers of the 1922 Colorado River Compact , which determines allocation of the river’s water, seriously overestimated actual future river flow, seriously underestimated future water demand, and did not foresee the impacts of climate change. These forces have resulted in a water deficit of almost 1 million acre-feet a year in the Colorado River system. Lake Powell and Lake Mead reservoirs together have been hovering at about 50 percent of capacity and scientists predict that they will probably never fill again.
To further complicate water supply concerns, recent scientific studies predict the water supply in the West to be reduced drastically over the next few decades. By 2050, University of Washington scientists predict the flow of the Colorado River to decline by one third. During the past decade of drought, many scientists studying tree ring evidence suggest that the West is actually experiencing a return to normal drier climate conditions.
In reality we may be reentering a low water period that has not been seen for the last 500 years. If the predictions of climate models are correct, the Colorado River water supply will continue to decrease. It is imperative for the sustainability of the West that our current inefficient water management system be altered. As the most destructive and least useful water project ever constructed, operation methods at Glen Canyon Dam must be re-evaluated. It is the duty of water managers in the West to secure a sustainable system for the Colorado Basin of the future.
The remarkable potential for large-scale ecological restoration is already apparent. As Lake Powell reservoir has declined, dozens of miles of the main canyon and hundreds of miles of side canyons have been exposed for the first time in decades. Ecosystems are healing. People are beginning to explore the emerging backcountry. There is also evidence that damage to the Grand Canyon’s ecosystems can be substantially reversed. Temporary management changes that mimic natural river flows have partially replenished sediments and improved endangered fish habitats. These environmental benefits could be made permanent under GCI’s “Fill Lake Mead First” strategy.
Lake Powell: Unnecessary for Water Delivery
The original goal of Glen Canyon Dam was water security; that is, water storage to ensure delivery to the Lower Basin and protection of the water dowry of the Upper Basin states. Under the Colorado River Compact of 1922 , the upper basin is required to deliver 8.23 million acre-feet (MAF) of Colorado River water to the lower basin and Mexico every year. We now know that annual delivery requirements were based on flawed projections suggesting that annual river flow was equal to 16.5 MAF annually. More than eighty years since the Compact was signed, the average annual flow has proven to be closer to 13.5 MAF.
In addition, due to its high desert location and huge surface area, Lake Powell loses an average of 860,000 AF of water annually to evaporation and bank seepage – enough water to supply the entire City of Los Angeles.
Lake Powell loses more than 6% of the Colorado River’s annual flow — more than three times Nevada’s annual allotment.
Since completion of the Dam, more than 34 MAF of Lake Powell water has been lost to evaporation and bank storage.
The water lost is Upper Basin water: Glen Canyon Dam actually makes it more difficult to fulfill the delivery requirement of 8.23 MAF of water to the Lower Basin.
In San Diego water prices – based upon the price used in the ongoing negotiations for the sale of Colorado River water by the Imperial Irrigation District to San Diego – the water lost at Lake Powell each year is worth $225 million dollars.
Since 1963, more than 34 MAF of water has been lost from Lake Powell; worth about $9 billion.
All Dams are Temporary – Sedimentation
Because dams are built to store water, they also store the sediment that all rivers carry. This sediment builds and steadily decreases the storage capacity of the reservoir. Ultimately all dams fill with sediment or are destroyed by natural floods.
Built in 1963, Glen Canyon Dam is 563 feet high and has steadily been filling with the equivalent of 30,000 dump truck loads of sediment every single day—100 million tons of sediment annually.
Arsenic, lead, selenium, boron, and mercury from upstream sources are currently trapped in the sediments of the reservoir, rather than flowing harmlessly to the sea, as they did prior to the dam.
The flooding of Glen Canyon covered a yellowcake uranium mill tailings pile near Hite which may pose health risks to fish, wildlife, and humans who visit Lake Powell.
As sediment builds up in Lake Powell reservoir, water storage capacity steadily decreases, and will ultimately fill the reservoir completely.
Scientific studies predict that without the reservoir, sediment deposits in the main channel upstream of the dam could be flushed out in as little as five years (CEA).
Glen Canyon Can Be Restored
We have a chance to address both the water supply and environmental crises at the same time. It is no longer viable to maintain two half-empty reservoirs — Lake Powell and Lake Mead. A more practical alternative would be to consolidate most of the water from both reservoirs in Lake Mead, with Lake Powell used as a backup in flood years, as illustrated in our Fill Mead First approach.
This strategy would not solve all of the problems facing the Colorado River Basin, but it would have many benefits for the people and ecosystems of the region. It would help to maintain a reliable water supply for millions of people who depend on Lake Mead. It would allow water to flow more naturally through Glen Canyon Dam, helping to heal Grand Canyon ecosystems. It would also permanently lower Lake Powell, exposing many more portions of Glen Canyon that have been flooded under the reservoir and allowing their recovery.
A few years ago, this kind of fundamental change seemed impossible. Today, as the pressure on the Colorado River system grows, policy makers and water managers are open to new ideas that they never would have considered before. The public is becoming aware of the problems and recognizing the need for positive change. If we act soon, we can ensure a sustainable water supply and heal much of the damage to Colorado River ecosystems. This is the purpose of GCI’s Glen Canyon Restoration Campaign.
Read more about Glen Canyon history and issues by following : 1922 Colorado River Compact, Lake Powell Reservoir: A Failed Solution, Sedimentation, Dam Construction & Engineering, Environmental Movement History, History of the Bureau of Reclamation, and the History of the River Restoration Movement.