Vol. 2, No. 4, May 2002
The Bureau of Reclamation (BuRec) is working on another public relations charade to combat mounting pressure that it is not doing enough to stop the decline of the Grand Canyon ecosystem caused by Glen Canyon Dam. As a result they are contemplating a two-year series of experimental flows from Glen Canyon Dam to improve habitat conditions for humpback chub, an endangered native fish. But like similar exercises conducted over the past five years, these too are doomed to fail.
According to Dave Haskell, retired science director for Grand Canyon National Park, "The three key things this ecosystem needs are warmer water, sediment, and annual high flows to distribute sediment into the system. These experiments will not provide this."
Ninety to ninety-five percent of the sediment Grand Canyon needs remains trapped behind Glen Canyon Dam. Lack of sediment and driftwood has eliminated beaches and changed the carbon base, which in turn has caused the near disappearance of the Canyon's natural food web. The historic food source for native fish has vanished; no insects native to the Canyon remain and riparian vegetation is struggling in the sterile soil.
At best these experimental flows will move a tiny fraction of the Canyonís remaining sediment. Moreover, since these flows are not designed to exceed 45,000 cubic feet per second, when pre-dam flows were routinely twice this, the overall benefit to native fish and plants will be further compromised.
Manipulating the dam won't change the chilly water temperatures either. Water released from Glen Canyon Dam is a constant 46° F., causing the river temperature to seldom exceed 55° F. Native fish require warmer water with temperatures reaching 80° F., the natural pre-dam summer temperature of the water.
In 1996 BuRec received a huge public relations boost for implementing simulated flood flows from the dam, but the native habitat gained nothing. "Here we are five years and $40 million later, ready to repeat history," says John Weisheit, LIVING RIVERS' Conservation Director. "That's why we are building a new Grand Canyon Restoration Coalition to mobilize widespread support for true restoration of the Grand Canyon."
