The Glen Canyon Dam, which was completed in 1963, is one of several multipurpose storage reservoirs on the Colorado River system. The initial operating rules for the Dam were designed to meet requirements for the delivery of water and to yield maximum hydropower revenues through the production of peaking power. Since the early years of its installation, however, the Dam has created new concerns about environmental resources in the Grand Canyon. The Glen Canyon Environmental Studies (GCES), which have been in progress since 1982 under sponsorship of the Bureau of Reclamation, are intended to support the scientificevaluation of relationships between the operations of Glen Canyon Dam and the natural resources of the Grand Canyon. The results of the GCES have been used recently in evaluating a range of possible operating rules for the Dam, in supporting the analysis of alternatives to be listed in the Glen Canyon Dam Environmental Impact Statement, and in setting the stage for long- term monitoring of environmental resources in the Grand Canyon.
Since 1986, the NRC’s Committee to Review the Glen Canyon Environmental Studies has evaluated GCES reports as well as other documents produced by the Bureau of Reclamation. The present NRC report provides a review of the Bureau’s Draft Federal Long-Term Monitoring Plan for the Colorado River below Glen Canyon Dam. The committee’s review deals with all aspects of the draft monitoring plan, including scope of work, protocols for acquisition and archiving of environmental data, organization,justification, and implementation.
The NRC committee believes that the draft monitoring plan will be of great importance in providing a rational basis for protection of environmental resources in the Grand Canyon. In addition, because of the national and international prominence of the Grand Canyon, as well as the intensive studies that have been sponsored through GCES, the plan may serve as a blueprint or model for other riverine ecosystem monitoring plans in the United States and other countries. For this reason, it is important that the plan be well-designed, clearly explained, and efficient in its proposed collection of data and use of financial resources. The NRC committee believes that the present draft of the long-term monitoring plan does not yet meet all of these criteria.
The present version of the long-term monitoring plan does not contain any estimates of the costs of environmental monitoring, nor does it make any firm recommendations for research that would complement monitoring. The NRC committee believes that these two critical elements should be added to the plan. Given the extensive experience of GCES program personnel with the cost of working in the Grand Canyon over the last decade, it seems reasonable that the plan should provide an estimate of the expenses of monitoring. Failure to specify costs may result in arbitrary omissions from the list of essential variables to be monitored, which would undermine the effectiveness of the monitoring program. As an adjunct to the estimate of cost, it may be necessary for the plan to show in more specific terms what limits of error are acceptable for key variables to be monitored.
Research is also important because monitoring will probably demonstrate some unexpected results; program managers should support research that may help to explain these unexpected results. The draft plan correctly indicates that an important role of research is to improve the efficiency of monitoring. The plan is tied specifically to the preferred alternative for operation of the Dam as derived from the Environmental Impact Statement. The NRC committee believes that the program should extend beyond this to include information that would be relevant to analysis of other potential operations of Glen Canyon Dam that might arise as the preferred alternative is revised or changed due to other causes within the scope of dam operations.
The committee finds a number of problems with frequency of measurement and scope of data collection, both of which may be inadequate for components of the environmental system. In addition, the plan indicates that monitoring should be conducted by noninvasive means, but offers limited guidance in support of this objective. The committee supports greater emphasis on noninvasive methods for studying the Colorado River and is particularly interested in removal of permanent physical installations that are now used in monitoring.
Many parts of the draft monitoring plan are not sufficiently specific about monitoring requirements. For a number of resources, the frequency of monitoring, the sites for monitoring, and the methods for monitoring are not described or are described only in vague terms. Given the long-term commitment that will be essential, and the necessity for stability in data collection, it is important that the monitoring plan be more specific.
In a number of instances, the draft monitoring plan subordinates specific requirements for information to administrative initiatives that will be developed in the future by various resource management agencies outside the long-term monitoring program. The committee believes that the long-term monitoring program must take full responsibility for decisions about the kinds of data to be collected, sites at which data will be collected, and methods for data collection. Blanket delegation of this responsibility to other entities is undesirable and should be avoided.
Unfortunately, the NRC committee finds much of the present version of the draft long-term monitoring plan to be confusing. The plan needs to be extensively revised for improvement of clarity, logical cohesion, and degree of specificity with which monitoring requirements are described.
Finally, the draft monitoring plan does not contain any proposal for administration or management of long-term monitoring. Strategies for administration and management are critical to the success of the program, and should be incorporated in the plan. If the plan does not include a specific proposal for administration, then criteria that must be satisfied by any proposed administrative scheme should be specified. The authors of the plan should consider the advantages of requiring administrative independence for the long-term monitoring program, and open contracting procedures that will allow the managers of the program to maximize cost efficiency and maintain direct control over the scope and quality of data collection in the Grand Canyon.