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LR Letter
October 30, 2002

Comments on Glen Canyon Dam experimental flows

Mr. Randall Peterson
Bureau of Reclamation, Upper Colorado Region
125 South State Street, Room 6107
Salt Lake City, Utah 84138-1102

Via Fax: 801-524-3858

Re: Proposed Experimental Releases from Glen Canyon Dam and Removal of Non-Native Fish, Environmental Assessment

Dear Mr. Peterson,

Living Rivers appreciates this opportunity to submit the following comments on the Environmental Assessment (EA) concerning proposed experimental releases from Glen Canyon Dam and removal of non-native fish from Grand Canyon National Park, September, 2002.

Living Rivers is keenly aware of the rapidly declining Humpback Chub populations, as well as other Grand Canyon native fish species, caused by the operations of Glen Canyon Dam. While the purpose of this EA is in response to the need to modify the operations of Glen Canyon Dam and to test methods to mitigate these impacts, the proposed actions, especially as they pertain to sediment retention and habitat-building, are fundamentally flawed. Of critical concern, this EA does not evaluate any alternatives for meeting sediment needs blocked by Glen Canyon Dam into the Grand Canyon river corridor. 

Adequate attention to sediment retention and augmentation experiments for native fish in Grand Canyon necessitates a full Environmental Impact Statement (EIS) not the cursory analysis undertaken in this EA. Such an EIS must fully evaluate the decommissioning of Glen Canyon Dam as an alternative. The need for such an EIS stems far beyond the issue of sediment, but to all aspects of the dramatic decline in Grand Canyon Humpback Chub populations. The reduction to just 2,000 adult Humpback Chub constitutes significant and new information to that which was evaluated in the 1994 Fish and Wildlife Service Biological Opinion, and 1996 Final EIS on Glen Canyon Dam operations.

Lastly, as stated in our letter of September 25, 2002, the public review process for this proposed action has been wholly unsatisfactory. The Bureau of Reclamation (BuRec) and its Adaptive Management Program for Glen Canyon Dam (AMP) must overhaul its procedures for public participation.

1. No sediment to justify experimentation

The EA focuses on utilizing experimental flows from Glen Canyon Dam to manage sediment for the benefit of Humpback Chub populations. However, there has been, and may not be during the proposed experimentation period, much sediment to manage. Thus, such experimentation may not occur at all. Ninety five percent of the historic sediment load for Grand Canyon native fish remains trapped in Lake Powell reservoir. In the best of conditions, such experiments as proposed in the EA, could manage only five percent of what would exist in natural conditions. However, this five percent has not proven sufficient to provide the turbidity and food base needs for the Humpback Chub. Furthermore, recent sediment inflows from the Paria River, the principle source for this remaining five percent (and the proposed experiments), have been the lowest since 1923. The EA did not report this. Such sediment inflows are not sufficient to allow for the proposed experimentation, and thus will in no way benefit the Humpback Chub.

Sediment is a key missing component for advancing the recovery of native fish in Grand Canyon (Rubin, et. al., EOS v83, n25, 2002). However, the EA focuses on flow releases to transport the sediment without insuring the availability of sufficient sediment to aid recovery. BuRec must therefore address through an EIS process methods to augment the remaining sediment inflows.

2. Climate change and the associated effects on long-term habitat improvement

The EA ignores climatic factors that will effect the proposed experimental releases. As noted above, without significant sediment augmentation the anticipated input of sediment and nutrients for the Colorado River main stem in Grand Canyon may not occur. Scientists from the US Geological Survey (USGS) have reconstructed the historic climate conditions for the Colorado River basin. Their reports indicate that a sustained severe drought could lie before us and that such a climate regime would jeopardize resource management challenges. (Hereford and Webb, 2002).

Another climatic factor that inhibits the proposed conservation strategies is below normal levels for Lake Powell reservoir; specifically reservoir levels set below the spillway portals. Presently, the spillway portals are perched above the reservoir, which will not provide for experimental flows above 45,000 cfs. If below average inflows into Lake Powell reservoir continue, resulting in additional elevation decreases, maximum discharge could be reduced an additional 50 percent or more. Such discharge rates would be ineffective to transport sediment as called for in the EA, even were such sediment available for transport. 

3. Timing of spike flows and sediment deposition will provide no benefits to native fish rearing

Under ideal circumstances, fall sediment inflows from the Paria River will be conserved through low flow dam releases until January, at which time a spike flow is to occur in an effort to build beaches and habitat for the rearing of Humpback Chub. However, previous experiments have revealed that much of this habitat disappears within six months of the spike flow. Since rearing Humpback Chub would not be available to utilize such habitat until five months following the spike flow, it makes little sense to time such flows so far in advance. To be of any benefit, such spike flows should be timed to coincide with the natural high flows entering Lake Powell reservoir.

4. Proposed flows ignore Fish and Wildlife Service opinion for the recovery of Humpback Chub

The EA states that the present flow regime from Glen Canyon Dam (Modified Low Fluctuating Flow or MLFF) has failed to benefit the habitat of the Humpback Chub. This conclusion came from data provided by the Grand Canyon Monitoring and Research Center (GCMRC) (Coggins and Walters 2001), which concludes that a dramatic reduction in the Humpback Chub population has occurred since this flow regime was implemented.

This flow regime was selected as the preferred alternative by the Secretary of Interior despite objections by the Fish and Wildlife Service FWS in its 1994 Biological Opinion. That opinion specifically stated that the MLFF alternative would "likely destroy or adversely modify designated critical habitat." FWS recommended the alternative known as the Seasonally Adjusted Steady Flow (SASF). FWS in conjunction with the Department of Biological Sciences at Northern Arizona University, reiterated these recommendations in their September, 2002 report,  Monitoring and Research: The Aquatic Food Base in the Colorado River, Arizona during 1991-2001 (Benenati, et. al.). This report states, "We recommend a decade of Seasonally Steady Flow alternative, with spring beach building flows as the climate permits and unlimited hydropower ramping within 10% of the predicted seasonal mean. We feel these flows in combination with alien fish suppression and thermal modification of GCD could make Grand Canyon a sanctuary for native fishes of the Colorado River basin."

The proposed experimental releases outlined in the EA will continue to conflict with these recommendations in two ways. First, as noted above, the habitat-building releases do not occur at the preferred time-period of the annual, historic snowmelt, to which these native fish are naturally attuned. Second, the prescribed fluctuating flows for non-native fish suppression would disrupt the food supply for the native fish species. Additionally, the EA does not sufficiently analyze the impacts to other habitats, with their associated species, caused by experimental releases inconsistent with the river's natural hydrograph.

5. Supplemental EIS needed

The proposed actions in this EA, either separately, or in combination with other actions contemplated by BuRec and AMP, are not seriously addressing the precipitous decline of endangered Humpback Chub in Grand Canyon National Park. This decline, described by Coggins and Walters, while not surprising given lack of management activities on behalf of the Chub, was not anticipated when the Record of Decision was signed. The population has been considered to be fairly stable over the last decade or more. Therefore, under National Environmental Policy Act (NEPA) regulations found at 40 CFR 1502.9(c)(1)(ii), these new data represent "significant new circumstances or information relevant to environmental concerns," triggering a requirement to prepare a Supplemental EIS (SEIS) to the 1996 Glen Canyon Dam EIS. The Bureau of Reclamation, the National Park Service, and other agencies are likely in violation of the Endangered Species Act and the Grand Canyon Protection Act for failing to ensure protection and recovery of the Humpback Chub population in Grand Canyon National Park. BuRec, in conjunction with National Park Service, and other relevant agencies, should immediately begin work on such an EIS for the full recovery of the Humpback Chub populations in Grand Canyon National Park. Such an EIS must address all issues affecting the Humpback Chub including: temperature, sediment and nutrients, flow conditions and non-native fish impacts. Most importantly, the EIS must evaluate the decommissioning of Glen Canyon Dam as one of the alternatives to meet Humpback Chub recovery objectives.

6. Public review process

BuRec did not fully comply with the spirit of the public review process as outlined by NEPA. Less than ten days notice was given prior to its two public meetings. No notification was mailed out in advance of, or subsequent to, these meetings. As a result, less than a dozen people not directly affiliated with the activities of BuRec or the AMP attended the combined meetings. The EA was not made available to the public in advance of these meetings. With the exception of those few who attended the first meeting in Flagstaff, Arizona, to obtain a copy of the EA, most others were afforded less than 30 days for which to formulate and submit comments.

The AMP is charged to fully involve the general public in its activities. We request that in the future BuRec assert greater diligence in the future concerning public participation and ensure that ample time is given to the public to learn about, and become engaged in, those activities pertaining to the operations of Glen Canyon Dam, and its associated impacts to Grand Canyon National Park.

In conclusion, Living Rivers finds this EA and the experiment proposed pertaining to sediment, an unfortunate waste of public resources. The crisis facing the Humpback Chub in Grand Canyon is quite serious, but it has yet to be taken seriously by BuRec and the AMP. The proposed habitat-building experiment is unlikely to materialize due to lack of available sediment. Even if such sediment were available, it would not be distributed in a timeframe to benefit the Humpback Chub. Regardless, such sediment would be insufficient to mitigate the loss of 95 percent of sediment and nutrients now trapped behind Glen Canyon Dam. This EA further demonstrates BuRec's and AMP's unwillingness to follow the recommendations of FWS, and as a result, will lead to the further declines in the Humpback Chub populations in Grand Canyon National Park. BuRec must abandon this EA and proposed experimentation and conduct a full EIS on new operating regimes for Glen Canyon Dam, including decommissioning, to fully recover endangered fish habitat in Grand Canyon National Park.

Thank you for the opportunity to submit these comments and recommendations.


John Weisheit
Conservation Director
Living Rivers

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