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Description of Alternatives <br />Resources in the Glen Canyon reach that would be adversely impacted <br />include sandbars, riparian vegetation and associated terrestrial wildlife, <br />Cladophora and associated algal and invertebrate communities, a <br />regionally important trout fishery, recreation potential, Native American <br />cultural and sacred sites, and archeological and historic areas/sites. <br />Impacts to the Cladophora-based aquatic food chain could have effects <br />throughout Grand Canyon. <br />Most of these impacts would result from the greater frequency and <br />magnitude of fluctuations behind the reregulating dam constructed to <br />protect downstream resources from those same fluctuations. A reregu- <br />lating dam would require $60 to $110 million to construct and 5 to 15 years <br />to implement without any opposition. <br />Impacts in the Glen Canyon reach could be mitigated by reducing the <br />frequency and magnitude of daily river fluctuations. However, without <br />maximum fluctuations, there would be no need for a reregulation dam. <br />Reduced fluctuations and elimination of the reregulation dam create <br />conditions identical to those evaluated under other fluctuating flow <br />alternatives, including no action. <br />Eliminated Concepts <br />Some comments received during the scoping process suggested the <br />following concepts that were eliminated from detailed study. <br />• Sand pumping <br />• Beach protection <br />• Remove Glen Canyon Dam <br />• Move hydropower peaking from Glen Canyon Dam to Hoover Dam <br />Although sand pumping and beach protection were eliminated from <br />detailed study in this EIS, both could be considered during long-term <br />monitoring under adaptive management. <br />Removing the dam represents an alternative to the dam itself and would <br />not meet the CRSP project purpose. <br />Hoover Powerplant already is operated as a hydroelectric power peaking <br />plant. No excess capacity or energy is available at Hoover to substitute for <br />reduced peaking at Glen Canyon, as all of the capacity and energy at <br />Hoover is allocated by existing contracts. <br />Glen Canyon Dam EIS Summary 35