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Environmental Science Division

Glen Canyon LTEMP EIS

Glen Canyon Dam, a 1,300-MW water-storage and hydroelectric facility is located on the Colorado River upstream of the Grand Canyon. EVS is evaluating the effects of dam operations on the Colorado River.

A comprehensive evaluation of Glen Canyon Dam operations and their effects on the Colorado River through the Grand Canyon was completed by the Department of the Interior with EVS assistance. The Long-Term Experimental and Management Plan (LTEMP) Environmental Impact Statement (EIS) — the first such evaluation in over 20 years — examines how flow regimes can meet the goals of supplying water for communities, agriculture, and industry, and will protect the resources of the Grand Canyon while providing clean hydropower.

The LTEMP Final EIS, which was published in October 2016, will determine dam operations and management actions for the next 20 years. A significant portion of the LTEMP consists of planning for experimental manipulation of flow, temperature, and other variables, to evaluate uncertainties and improve understanding of the Colorado River ecosystem’s response to dam operations.

Argonne efforts for this project included:

  1. Synthesizing existing information and scientific findings during the past 20 years;
  2. Identifying alternative dam operations and other actions to be considered in the LTEMP EIS;
  3. Developing an experimental approach to addressing uncertainties; and
  4. Analyzing the effects of several alternatives.

The Argonne LTEMP EIS team consisted of aquatic and terrestrial ecologists, hydrogeologists, cultural and tribal resource specialists, recreation scientists, socioeconomists, and power systems engineers. The Argonne team used both preexisting and project-specific models to evaluate the effects of operations on sediment transport, beach building, water temperature and quality, endangered fish populations, riparian vegetation communities, socioeconomic effects, and the market value of power resources.

EVS staff participated in a sandbar and riparian vegetation monitoring trip with U.S. Geological Survey Grand Canyon Monitoring and Research Center staff in October 2012. [Source: Argonne National Laboratory]

Argonne staff members have considerable expertise in studying the effects of hydroelectric generation on downstream resources in the Colorado River basin. Since the early 1990s, Argonne has conducted a number of important activities in the basin that have established the Laboratory’s reputation for science-based environmental protection compliance. These activities include a study of flow regime effects downstream of Flaming Gorge Dam using multispectral aerial videography, habitat and modeling studies of endangered fish species in the middle Green River (a tributary of the Colorado River), studies of the effects of annual flood flows on endangered fish habitats, participation in a multi-agency task force to develop flow and temperature recommendations below Flaming Gorge Dam, and numerous science planning efforts for other hydroelectric facilities in the basin.