The Necessity of Sediment

The Colorado River historically carried an average of 275,000 tons of sediment through the Grand Canyon every day. Combined with huge spring floods and dynamic flow patterns, this nutrient-rich sediment helped to replenish beaches, sandbars, and other natural aquatichabitats for fish and wildlife in the area. Glen Canyon Dam now blocks 95% of this crucial sediment, preventing nutrient delivery and quickly deteriorating sediment levels within the Canyon.


Saving the Grand Canyon… Once Again

Shortly after Glen Canyon Dam was authorized by Congress, the Bureau of Reclamation announced plans to build two giant dams in the Grand Canyon that would flood this gem of the National Park System. Having realized too late the unbearable sacrifice of Glen Canyon, public opposition swelled and soundly defeated the Grand Canyon dams. Forty years later, we have learned that the Grand Canyon is in peril once again. Starving for a free-flowing Colorado River, the fragile ecosystem of the Grand Canyon is in need of public support once again.

On a visit to the Grand Canyon in 1903, Teddy Roosevelt spoke to a group of bystanders, insisting that protecting the Grand Canyon was a basic duty of the American people. Expressing his concern, he said, “Keep this great wonder of nature as it is. Do nothing to mar its grandeur, for the ages have been at work upon it. Keep it for your children, your children’s children, and all who come after you.”

Sadly, in 1963, Roosevelt’s warning was officially ignored with the completion of Glen Canyon Dam, twelve miles above Lee’s Ferry and Marble Canyon. The warm, sediment-laden natural flow cycle of the Colorado River was impounded by the massive 710-foot dam, and cold, clear, regulated flows were released into the Grand Canyon. This drastic change in water quality has damaged the Colorado River ecosystem, endangered many native plant and wildlife species, and reduced sediment levels necessary to the survival of the Canyon.

Cold Clear Water in the Desert?

Water released from Powell Reservoir is released from the bottom of the dam, causing the water to be unnaturally cold. River temperatures that used to range from 35-85 degrees annually are now a steady 46 degrees year round. Native fish species have difficulty spawning in the cold water, which has caused drastic reductions in fish populations. Following dam construction, non-native species were introduced to the Canyon. These species thrive in cold clear water rivers, increasing competition and predation of native species.

Endangered Species

The Colorado Pikeminnow, and the Bonytail Chub, fish species native to the Grand Canyon, have been completely wiped out because of Glen Canyon Dam. The Humpback Chub and the Razorback Sucker are currently listed as Endangered Species and are at risk of similar consequences. In fact, despite efforts to alter flows from the dam to better mimic a natural flowing river, only about 1100 adult Humpback Chub remain in the Colorado River. In less than forty years, the cold, clear water from Glen Canyon Dam has done untold damage, causing the extirpation of rare native fish and other wildlife in the Grand Canyon. With shrinking populations, these endangered species face a grim future unless the natural flows of the Colorado River are restored.

Growing Public Support for the Grand Canyon

Shortly after Glen Canyon Dam was completed, the negative downstream impacts became apparent and over the next thirty years, as the health of the fragile ecosystem declined, public concern over the health of the Grand Canyon steadily grew. In 1982, the Bureau of Reclamation initiated a science-gathering program called Glen Canyon Environmental Studies to measure the impacts of Glen Canyon Dam on the Grand Canyon Ecosystem. In 1989, an Environmental Impact Study (EIS) on the operation of Glen Canyon Dam was announced. Under the Bureau of Reclamation’s direction, the EIS considered a specific assortment of dam release options, excluding the option of decommissioning Glen Canyon Dam. The Bureau of Reclamation was slow to begin work on the EIS until the United States Congress stepped in and ordered the timely completion of the study by passing the Grand Canyon Protection Act.

The Grand Canyon Protection Act of 1992

Signed into law in 1992, the Grand Canyon Protection Act (GCPA) directs the Secretary of the Interior to take decisive action in order to protect and preserve the Grand Canyon ecosystem. It specifically reads, “The Secretary shall operate Glen Canyon Dam in accordance with the additional criteria and operating plans specified in section 1804 and exercise other authorities under existing law in such a manner as to protect, mitigate adverse impacts to, and improve the values for which Grand Canyon National Park and Glen Canyon National Recreation Area were established, including, but not limited to natural and cultural resources and visitor use.” In essence, Glen Canyon Dam is to be operated in such a way that the health of the Grand Canyon ecosystem would take priority over other initiatives, such as maximizing hydropower generation. The Act also required the ongoing operational EIS to be completed in a timely manner. Despite the clear mandate, action taken by the Bureau of Reclamation has fallen far short of fulfilling the congressional intent of the Act.

The Artificial Flood of ’96

Shortly before the completion of the EIS in 1996, Secretary Bruce Babbitt authorized an artificial flood in the Grand Canyon to help rebuild beaches and habitats that had been scoured away by the clear water releases from the dam. In an attempt to mitigate the damage to the Grand Canyon, the Bureau of Reclamation released an artificial flood designed to mimic the high flows of former spring runoffs. While the flood temporarily restored beaches and improved backwater habitat, less than a year later, the beaches and new habitat were gone–eaten away by the clear sediment-hungry water.

Completion of the EIS and the Adaptive Management Program and the Grand Canyon Crisis

The EIS was completed shortly after the flood of ’96 and a Modified Low Fluctuating Flow (MLFF) was recommended for dam operations. To measure the effects of the new operational guidelines of the dam, the Adaptive Management Program (AMP) was also initiated to ensure that the protection mandate of the Grand Canyon Protection Act was fulfilled. Consisting of various stakeholders in the Grand Canyon (including the traditional water and power interests, relevant government agencies, the affected tribes, and recreation and environmental representatives), the Adaptive Management Workgroup (AMWG) makes recommendations to the Secretary of the Interior on how to operate the dam based upon scientific evidence. While appearing structurally sound, the consensus-building AMP process has been fraught with difficulties since it began in 1997.

AMWG has essentially become ineffective in solving the Grand Canyon’s growing problems while costing taxpayers upwards of $10 million annually. Two major baseline resources in the canyon (sediment and native fish) have been steadily monitored and have each demonstrated downward trends. Endangered native fish populations, (namely the Humpack Chub), have dropped from 5000 to 1100 since the passage of the Grand Canyon Protection Act. Of the few “band-aid” approaches attempted by the AMP to keep the precious sediment in the system, none have succeeded in the long term.

While some traditional stakeholders in AMWG work to stall progress in the canyon by proposing these “band-aid” solutions, the health of this biological gem is steadily deteriorating and endangered species populations continue to decline. The Bureau of Reclamation has studied many different options for operating the dam that would prevent further harm to the Grand Canyon., So far, they have been unsuccessful. The environmental studies in the Grand Canyon, costing more than $100 million taxpayer dollars since inception, have provided conclusive evidence that Glen Canyon Dam is the major source of environmental problems in the Grand Canyon. The only real solution for the declining health of the Grand Canyon is a free-flowing Colorado River.

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