Press Release Nov 12, 2014

Colorado River Rushes Through the Grand Canyon

High flow release is welcomed as significant for Grand Canyon National Park resources

A huge surge of water released into the Colorado River this week from the Glen Canyon Dam is being hailed by National Parks Conservation Association (NPCA) as an important measure to support endangered fish and help other natural and cultural resources in Grand Canyon National Park.

“This specially timed ‘high flow’ mimics pre-dam floods and will bring in sediment to build up sandbars along the river’s bank,” said David Nimkin, Southwest Regional Director for NPCA. “It will provide spawning habitat for fish and other wildlife species, better recreational opportunities for Grand Canyon boaters and other visitors, and keep sacred Native American cultural sites protected from the elements.”

The Department of Interior, (DOI) which operates Glen Canyon Dam upstream from the Grand Canyon, is releasing the water as part of an experimental protocol resulting from a 2012 environmental assessment. The goal of the protocol is to continue to fulfill the mandate of the 1992 Grand Canyon Protection Act, which stipulates that Glen Canyon Dam operations adapt with strong scientific research, to better protect the natural, cultural, and recreational qualities of the river within Grand Canyon National Park.

“Grand Canyon National Park is a beloved national treasure, visited by nearly 5 million visitors last year, generating $467 million in economic benefit,” said Nimkin. “Managing the Colorado River to protect natural conditions in the Grand Canyon makes good ecological and good economic sense.”

Since it was built in 1963, Glen Canyon Dam has regulated the amount of water that flows in the Colorado for its 277-mile stretch through the Grand Canyon. The dam was built to provide an inexpensive source of power for Southwest cities and industry, provide flood control, and store water for farms and communities in the region. Prior to the 71-story dam being erected, the river’s seasonal peak floods averaged over 93,000 cubic feet per second (cfs). Since then, the flow of water through the dam’s generating turbines has typically fluctuated between 8,000-25,000 cfs, according to power demand.

Several decades of such highly restricted water flow dramatically altered the conditions of the Colorado River and the canyon itself, prompting Congress to act to protect Grand Canyon National Park.

This week’s high flow surge, which takes place over five days, began at 9,000 cfs and will ramp up to a peak of 37,500 cfs. This will be the third consecutive year that DOI has staged a fall experimental high flow surge. These surges do not alter the amount of water that can be released, which is limited by state and international law, just the degree of fluctuation within a given period. DOI will incorporate data from these experiments, as well as other recent research, in an upcoming management plan that will aim to balance the municipal, industrial, agricultural, cultural, recreational, and environmental interests at stake in the Colorado River and the Grand Canyon in years ahead. A draft plan is anticipated to be released for public comment in early 2015.


About National Parks Conservation Association
Since 1919, the nonpartisan National Parks Conservation Association (NPCA) has been the leading voice in safeguarding our national parks. NPCA and its more than one million members and supporters work together to protect and preserve our nation’s natural, historical, and cultural heritage for future generations. For more information, visit

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