Thursday, October 21, 2004

8. PUBLIC LANDS: Newly exposed areas in Lake Powell require management plan, enviros say

April Reese, Land Letter Southwest reporter

SANTA FE, N.M. -- As long-inundated side canyons emerge in drought-shrunken Lake Powell, a debate over how to manage the newly exposed lands is surfacing as well.

When Glen Canyon Dam was completed in 1963, Glen Canyon and its side canyons filled with water, forming Lake Powell. Now, after several years of drought, reservoir levels have dropped to about 40 percent of capacity, exposing canyons and rock formations that had been submerged for decades. Tourists are now hiking in areas that used to be under water, and willow, gambel oak and other vegetation is reclaiming the newly emerged lands, providing new habitat for various species.

With so much new land exposed in the Glen Canyon National Recreation Area, environmental groups are pressing the National Park Service to come up with a plan to manage it. "These areas are spectacular. It's far exceeding anyone's expectations for how fast the restoration could happen." said Chris Peterson of the Glen Canyon Institute, which sent a letter to the Park Service last week urging the agency to develop a management plan for the area. "I've seen mountain lion tracks, birds -- the full range of species that used to live there are taking it back over as prime habitat. But the park service has no plan to protect these areas."

Cathedral in the Desert was flooded by the waters of Lake Powell around 1966, but its features are reappearing this year as the western drought continues. Photo courtesy of the Glen Canyon Institute.

About 40 miles of the San Juan River and 15 miles of the Escalante River, which merge with the Colorado River above Glen Canyon Dam, are now exposed, as well as roughly 40 miles of the Colorado itself, Peterson said. About 125 smaller side canyons are also emerging.

With hydrologists predicting that the drought could last a decade or more, the Park Service should come up with ways to protect those areas from overuse and preserve newly formed habitats, Peterson said. "Even though the dam was completed before the Endangered Species Act and the National Environmental Policy Act, those laws apply now," Peterson said. "Allowing those habitats to refill would violate those laws."

But federal wildlife managers say that because the habitat is likely to be temporary, it makes little sense to protect it. Instead, biologists are developing ways to ensure species that move into reservoir areas have a place to go when the water rises again. Jeff Humphreys, a biologist in the Fish and Wildlife Service's Southwest office, said the agency is beginning to consider the ebb and flow of habitat around reservoirs when drafting recovery plans for endangered species that colonize those areas. "By their very design, these reservoirs are there to store water during surplus years, and then provide water over a prolonged period, over the dry years. As that happens, the reservoir expands and contracts," Humphreys said. "We're starting to realize there will be these 'boom habitats' for species like the southwestern willow flycatcher that will be inundated."

In the case of the flycatcher, which has moved into exposed areas in Lake Mead, downstream from Lake Powell, FWS has identified nearby areas to which the flycatcher can retreat when the habitat becomes immersed again. Humphrey said those considerations are included in the new critical habitat designation for the bird, proposed last week (Land Letter, Oct.14).

Larry Crist, a biologist with the service's Utah office, under whose jurisdiction Lake Powell falls, said as far as he knows, no one in his office has looked at emerging habitat in Glen Canyon National Recreation Area.

Officials at Glen Canyon National Recreation Area could not be reached by press time.

The Bureau of Reclamation, which oversees the delivery of Colorado River water to users throughout the basin, has emphasized that the drought is temporary and that eventually the reservoirs will be replenished. But some hydrologists say the Colorado River's reservoirs may never rise to their former levels.

Will it rise again?

Tom Myers, an independent hydrologist based in Reno, Nev., who has studied Lake Powell, said that if the Colorado River Basin receives four years of above-average precipitation, reservoir levels could rise. But with the current demands on the system, it is unlikely that they will ever reach the old watermark, he said. The demand on the Colorado River system is about 16.5 million acre-feet (maf), including the 1.5 maf that the United States is obligated to deliver to Mexico. But the average flow is only about 13.5 maf, and about 1 maf is lost to evaporation from the reservoirs, he said. "The demand exceeds the flow by a few million-acre feet," he said. "So the numbers just don't add up to refill those reservoirs."

In the years after Glen Canyon Dam was built, the upper basin states were using very little of their Colorado River apportionment, and the lower basin states were using less than their legal share. But that is no longer the case, Peterson said. "I think it's the responsibility of our agencies to really look at our water delivery system and figure out its weaknesses. And Lake Powell is the weakest link," he said. "We can improve the system and get back one of the most spectacular places in the world. If we don't do anything about it, we're imposing huge costs on future generations."

Glen Canyon Institute is one of a handful of environmental groups calling for the decommissioning of Glen Canyon Dam to restore Glen Canyon and the river corridor in Grand Canyon National Park, just downstream from the dam. With about 825,000 acre-feet of water lost to evaporation from Lake Powell each year, sediment building up behind the dam, and greater public awareness of the loss of the Glen Canyon ecosystem, other storage options should be considered, the institute says.

"Now, 40 years later, we're realizing that Glen Canyon is not the best solution," Peterson said. "There are other places to store the water." For instance, aquifers along the Colorado River could easily store enough water to make up for the loss of Lake Powell, he said. Arizona is already storing some of its share of Colorado River water for future use, and other states could do the same, Peterson added.

Power and tourism interests counter that draining the reservoir would threaten electricity and water supplies and hurt local economies, which are largely dependent upon lake-based recreation.