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the construction of diversion and storage dams. A successful fish ladder has been built around the Redlands Diversion Dam. opening up 50 miles of historical habitat to endangered fish. The 350-foot long ladder is on the Gunnison River in southwest Colorado near the confluence with the Colorado River. Since the Redlands ladder was opened in 1996. endangered Colorado pikeminnow and other native fish have successfully used the ladder. A second ladder has been constructed on fhe Colorado River near Grand Junction, Colo. and plans call for two more ladders to be built along the river as well. Protecting endangered species within the basin is not restricted solely to fish. The Lower Basin is spending $4.5 million to develop an implementation plan for its Multi-Species Conservation Program (MSCP). The joint federal/stafe 50-year program is being designed to maintain, enhance and restore habitat for some 85 species (both plant and animal) living within the river's 1 aO-year flood plain. One of these species is the southwestern willow flycatcher, a federally endangered species that once thrived in the southwestern United States. The ~ One of the most provocative suggestions in recent years is a proposal to drain Lake Powell. the nation's second largest manmade lake which holds an average 26 million acre-feet of water (about two years of total average flows for the Colorado River). The reselVoir assists the Upper Basin with its delivery obligations to the Lower Basin. The gates at Glen Canyon Dam closed in 1964. Talk of restoring prehistoric American Indian archeological sites, riparian ecosystems and endangered fish species prompted the Sierra Club and the Glen Canyon Institute to spearhead a movement to permanently open the gates of the dam. Proponents argue that Lake Powell wastes 8 percenf of the Colorado's flow due to evaporation and seepage and that Glen Canyon Dam will eventually be rendered unusable because of all the trapped sediment. Proponents also say the natural hydrograph of the river is disrupted by Glen Canyon Dam, causing detriment to the environment. Supporters of the reservoir say Lake Powell is needed because it supports the local economy 24 Bureau began surveying the bird in the Lower Basin in 1996. Prior to this effort. it was generally accepted that the bird no longer existed on the lower Colorado River, as nesting had not been confirmed along the river since 1902. In 1996. researchers observed only six actual nesting attempts. By 1997. fhe number of documented nesting attempts had risen to 36. Still. scientists believe only 230 to 500 nesting pairs remain rangewide. Efforts are under way to ensure the protection of this species and the recovery program is expected to be fully implemented in 2001. The Upper and Lower Basin conservation and recovery programs are intended to correspond with the needs for future water and power projects on the Colorado River. Within the Upper Basin, over 40a projects have been awarded the go.ahead by the USFWS under the more stringent review process which must take into account the new endangered species listings. Some crifics contend that the recovery programs could impede water and power development if they are unable to obfain a favorable project review from the USFWS. Conversely. some environmental groups think the recovery programs do too little and to protest. they pulled out of a MSCP steering committee. through the 3 million annual visitors, is a major source of hydroelectric power (80 percent of the Colorado River Storage Project's electrical genera- tion occurs at Glen Canyon Dam) and ensures steady wafer supplies to the Lower Basin. Others stress that Glen Canyon Dam has helped the Upper Basin develop its apportionment by regulating flows and generating power revenues. A number of studies have been and are being conducted at Glen Canyon Dam under the Adaptive Management Program - created for fhe purpose of monitoring, experimentation. discussion and recommendations on operations at the dam. Currently. studies are being conducted for a temperature control device that would allow dam op- erators to pull water from higher in the reservoir where it is warmer and more closely approximates the natural temperature of river. A low flow study was conducted in the summer of 2000 when hydrologic conditions were lower than normal on the river. The test provides researchers with information related to water temperature. sediment deposition, vegetation and impacts to native and non-native fish species.