Click for next page ( 12


The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 11
1 Introduction and Background In writing about the Colorado River, John Wesley Powell (1895) noted the irony of snowmelt maintaining a riverthrough hundreds of miles of the honest and driest terrain in North America. Descending from almost 3 miles above sea level near Long's Peak in Colorado and in the Wind River range of Wyoming, the Colorado River's sources quickly reach flatter topography in Utah and Colorado while still more than a mile above sea level. The river continues its plunge toward sea level through canyons that ultimately trench the plateau to a depth of more than a mile. Because the canyons allow the river to seek its final level quickly, the Colorado moves with notorious energy. A modern irony equal to Powell's irony of ice water in the desert is that the Colorado River, known for its extraordinary rush to the sea, now typically fails to reach the sea at all. In Powell's day, water moved freely from the snow fields of the Rockies to the Gulf of California in 1 to 3 months, depending on the season. At present, only about 10 percent of the annual yield crosses from the United States to Mexico, where even this remnant is consumed before it can reach the Gulf of California. Although Powell nodded app- rovingly at evidence of prehistoric irrigation practices by Indian tribes along the Colorado (Powell, 1895), he would probably have been surprised to see the entire flow of the Colorado thus fully diverted for human use. The Colorado's flow is held by two very large reservoirs and many smaller ones, all of which comprise a total volume of 58 million acre-feet (Andrews, 1991), or approximately four times the mean annual flow of the river. Water passes from the reservoirs for consumptive use, most of which is accounted for by irrigation. As a significant by-product, the reservoirs of the Colorado River in aggregate produce about 13 billion kwh of hydroelectric energy 11

OCR for page 11
12 River Resource Management in the Grand Canyon (Plummer, 1983~. Of the many reservoirs that impound the Colorado, Lakes Powell and Mead are the most impressive; they are the two largest reservoirs in the western Unded States. The dams for these two reservoirs, which produce most of the electricity and hold most of the water of the Colorado River, together inundate over 300 miles of the river. While the two dams are of similar size and provide many of the same benefits, Glen Canyon Dam, which impounds Lake Powell, is of particular importance because it holds back the Colorado River in front of the Grand Canyon (Figure 1.1~. Congress authorized the construction of Glen Canyon Dam in 1956 as part of the Colorado River Storage Project Act. The dam was proposed by the Bureau of Reclamation (BOR), which assumed responsibility for its operation when the dam closed in 1963. The Glen Canyon Dam was a realization of the Reclamation Act of 1902, according to which arid lands of the American West would be extensively irrigated with waters from western rivers. Without a dam on the upper mainstem of the Colorado River, use of its water would have been inefficient and thus contrary to the goals of reclamation. Two factors added particular motivation to the construction of a dam on the upper mainstem of the Colorado River. First was the Law of the River, which includes not only the Colorado River Compact of 1922 but also all previous and subsequent statutes, judicial decisions, and treaties that affect the disposition of the river's waters (Ingram et al., 1990~. The Law of the River evolved under the assumption that the Colorado River could deliver at Lee's Ferry just over 16 million acre-feet per year, of which 15 million was to be divided equally between the states of the upper basin (Colorado, Utah, Wyoming) and the lower basin (California, Arizona, New Mexico, Nevada) and the remaining 1.5 million was to go to Mexico. By 1950, it was clear that this assumption was based on an overestimate, which, when combined with inevitable droughts, would either prevent the upper-basin states from using their full allocation or would cause them to default on their delivery obl igations to the lower basin (Dawdy, 1991~. A large dam on the upper mainstem would cover the immediate damage from miscalculation of the yield until such time as an extended drought might coincide with the upper basin's full use of its allocation. In addition, a dam on the upper mainstem would produce hydroelectric power revenues that could be used to finance delivery or storage of water throughout the basin (Ingram et al., 1991~. Without subsidy from hydropower, the BOR's constellation of water projects in the Colorado River basin would have been impractical, especially in the sparsely populated

OCR for page 11
~3 . . raw ~ am/ I... ~ ~ ~ ....... -On # ~ ~ ....... ~ ~ ; ~ . . . ~. ~ . . I. .... - ~1 . ~ .... . . . . / ~ . . . . .~ ~' ~ :,_ \ / 1 ~! I ~ / ~ 16 o = o ~- 1~ =~= . d~; ! =: 1 o ~ ~ . S ! ~ 1 =I 41 o a! =1 lo .. o ~ a ^ = w e a . . q o :: 0 ~ e e o

OCR for page 11
14 River Resource Management in the Grand Canyon upper basin, because most projects required strong external subsidies that could be sustained only by a revenue stream. Thus, the Glen Canyon Dam was not merely a reclamation project but also a guarantor of integrity for the Law of the River and patron of regional reclamation projects that otherwise would have perished for lack of cash. The Colorado River Storage Project Act listed beneficial use of water, reclamation of arid and semiarid lands, and control of floods as primary purposes of the Glen Canyon Dam. The act also mentioned hydroelectric power but only as an "incident" of other specifically mentioned purposes. In qualifying hydropower production in this way, the act ensured that power production would never challenge the Law of the River. Even so, Congress showed its concern for production of revenue by specifying that Glen Canyon Dam be operated in such a way as to produce maximum power at firm rates consistent with the overriding requirements for delivery of water. In practice, the secondary status of hydropower proved to be not very restrictive because the central requirementforefficient hydropower marketing is flexibility in hourly or daily scheduling of discharges, whereas such short time scales are typically irrelevant to the delivery of water for consumptive use (Hughes, 1991~. Power production and water delivery might come into conflict but only under the most extreme hydrological conditions. Thus, Glen Canyon Dam was able to deliver water, power, and money in quantity by using an operating regime that featured annual divisions of runoff between the upper-and lower-basin states and daily or hourly phasing of discharge in response to fluctuations in demand for power. Glen Canyon Dam aroused only minor opposition in the 1950s when it was authored. Most of the opposition came from the Bureau of Reclamation which initially rejected the site because of the problems caused by the soft sandstone. The site was a compromise selection in 1956 after con- servationists succeeded in stopping a dam on the Green River which would encroach on Dinosaur National Monument and traded Glen Canyon for no dam on the Green (Fradkin, 1981 .) In retrospect, it is clear that Glen Canyon Dam slipped through a partly closed door; two other mainstem projects (Marble Gorge and Bridge Canyon) running slightly behind Glen Canyon were killed by public opposition. Struggles over the authorization of new dams were so intense from 1965 to 1980 that they diverted attention from the operation of existing dams. Management principles for Glen Canyon Dam were essentially static for almost 20 years following completion of the dam, even though the political landscape metamorphosed drastically over this interval. A changed per

OCR for page 11
Introduction and Background 15 caption of the public welfare was evident as far back as 1968, when the Colorado River Basin Project Act broadened the definition of purposes for operation of the dam to include not only storage and delivery of water but also maintenance of water quality, outdoor recreation, and fish and wildlife. The 1968 act again listed power production as an incident of other purposes. The broadened purposes for operation of the dam were reconfirmed in 1992 with the Grand Canyon Protection Act, which cited the need to "mitigate adverse impacts to and improve the values for which Grand Canyon National Park and Glen Canyon National Recreation Area were established, including, but not limited to natural and cultural resources and visitor use." Several forces were behind Congress' decision to intervene in the operation of Glen Canyon Dam. The most important change in the legal frame of reference was the Endangered Species Act (ESA) of 1973. Although the ESA did not immediately change the operation of Glen Canyon Dam, it set the stage for operations that would be answerable to the welfare of the Colorado River's endemic fishes and possibly to endangered species of the riparian zone as well. The effect of the ESA was magnified by the National Environmental Policy Act (N EPA) of 1970, which assured an extended public examination of the welfare of endangered species and of other resources that had not been considered in the development of the original operating rules for the dam. Given that the NEPA required significant federal action as a trigger, however, it did not begin to affect the operation of Glen Canyon Dam until the 1 980s. New constituencies also developed around Glen Canyon Dam. The trout fishery of the dam's tailwater maintained a steady concern for the welfare and growth of trout, while the rafting industry, which is based on some 30,000 annual participants in short trips and 20,000 participants in long trips through the canyon (BOR, 1993), focused attention on the number, size, and stability of beaches for camping. Following judicial validation of their rights to the river's water, Native American tribes gradually also asserted their claim to evaluate the dam's operations. Finally, environmental groups, representing not only their members but also a more diffuse change in societal attitudes about environmental resources, showed their willingness to discard the initial assumptions upon which the operating rules were based. The traditional operating rules were of direct benefit to the consumers of power through the regional marketing network. Power from Glen Canyon Dam, although produced by the BOR through management of the dam, is marketed by the Western Area Power Administration (WAPA), an agency of the U.S. Department of Energy. Given that the daily and weekly operating

OCR for page 11
16 River Resource Management in the Grand Canyon schedules for the dam had been optimized around the marketing of power, any change in the operating rules could be expected to reduce the value of power from Glen Canyon Dam. WAPA spoke against changes in the op- erating rules on these grounds. The BOR was predisposed to identify strongly with WAPA's priorities. Not only had the bureau been directed in the original authorizing legislation for Glen Canyon Dam to produce maximum revenue from power, it had also assumed that revenue from the dam would sustain its other projects in the Colorado River Basin. Between 1970 and 1980, major changes in the operating rules for Glen Canyon Dam would have been difficult, even if the BOR had wanted to make them. Water delivery, flow control, and optimization of hydropower revenues presented a complex but deterministically soluble set of demands for release of wafer from the dam. In contrast, the requirements of endangered species, trout, recreation, and Native American tribes could not be specified even qualitatively because they had not been sufficiently studied. Priorto 1980, the BOR could find no basis for changing the operating rules of Glen Canyon Dam, even though an array of new resources had been added to the list of purposes for operating the dam. Before passage of the NEPA, federal management agencies had leg- itimately claimed that they were not authorized to study the environmental effects of management practices. NEPA reversed this line of reasoning overnight; studies were not only allowed, they were mandatory. In the early 1 980s the BOR foresaw the need to rewind the Glen Canyon generators and also proposed to increase generator capacity and adjust operations to increase output of peaking power. This led it to consider the preparation of either an environmental assessment or a full environmental impact statement (EIS). The bureau hoped to avoid an EIS, which would have been the first to examine the full scope of operations for a reservoir constructed prior to passage of the NEPA. To support its decision not to conduct an EIS the BOR needed data. To provide the data, it created the Glen Canyon Environmental Studies (GOES). The bureau at first constrained the GOES very narrowly, partly on the incorrect theory that the Law of the River precluded significant operational changes. Environmental data were to be collected primarily near the dam, and analysis of operating regimes that might result in significant loss of efficiency in hydropower marketing was prohibited. Analysis of aesthetic and cultural values was also ruled out of bounds. While needing to provide support for its contention that a small increase in generator capacity would have at most small environmental effects, the BOR clearly did not wish to

OCR for page 11
Introduction and Background 17 invite questioning of its fundamental operating rules. Rather than coming to a quick conclusion, however, the GCES merely proved with increased cer- tainty the need for environmental studies of broader scope. In administering and designing GCES, the BOR maintained its close working relationship with WAPA, which advised it on potential impairment of hydropower marketing that might result from changes in operation of the dam. In fact, the revenues gathered by WAPA from hydropower paid for the GCES program. In addition, the BOR created an interagency group con- sisting of agencies with responsibility for protection or management of environmental resources below Glen Canyon Dam. The agencies initially included the National Park Service, the U.S. Fish and Wildlife Service, and the Arizona Game and Fish Department but were later broadened to include Indian tribes with territorial or cultural interests in the Grand Canyon. Much of the push to extend and broaden GCES came from the resource man- agement agencies that, without the BOR, had no means of financing extensive studies of the resources below Glen Canyon Dam. The BOR was criticized externally for lack of credibility in conducting environmental studies. Although agencies with environmental responsibilities were well represented in the design and execution of the GCES, the bureau, in cooperation with WAPA, provided both the money and management for GCES. Given the BOR's historical commitment to water delivery and power production, its control of GCES presented at least the potential for conflict of interest. ROLE OF THE NRC Desiring to maintain credibility for its newly expanded studies, the BOR in 1986 requested that the National Research Council (NRC) form a committee to provide scientific reviews of the GCES. The NRC's Water Science and Technology Board sponsored the formation of a committee in 1986 (Table 1.1). The firsttask of the Committee to Reviewthe Glen Canyon Environmental Studies was to review the results of Phase I of GCES, which was nearing completion as the committee was being formed. The committee found considerable value in GCES but also criticized the program for insufficient geographic and conceptual scope, weak integration of components, lack of a clear master plan, and excessively internalized staffing of the research effort (NRC, 1987~. The committee called for external scientific oversight, inclusion

OCR for page 11
18 River Resource Management in the Grand Canyon TABLE 1.1 Sequence of Events for GCES Event Year 1. Initiation of GCES Phase I 2. NRC Committee on GCES appointed 3. Release of first NRC report 4. Initiation of GCES Phase 11 5. NRC sponsored review of USGS sediment study plan 6. Initiation of environmental impact study 7. Creation of federal cooperators group 8. NRC sponsored Grand Canyon symposium 9. Start of experimental flows for Glen Canyon Dam 10. Start of interim flows for Glen Canyon Dam 11. Addition of Indian tribes to cooperators group 12. Formation of GCES external advisory board 13. NRC review of the long-term monitoring plan 14. Release of U.S. Fish and Wildlife Service Final Biological Opinion on the humpback chub 15. NRC review of draft EIS 16. Release of final environmental impact statement 17. Record of decision for EIS - 1983 1 986 1 987 1987 1 988 1 989 1 990 1990 1991 1991 1991 1 993 1 994 1 994 1 995 1 995 1 996a aAnticipated of a senior scientist on the study team, more open contracting procedures, better planning and integration, and extension of scope. The committee had two objectives in making its final review of GCES. The first was to determine the degree to which GCES has been successful in providing a firm scientific basis for assessing the consequences of various management options for Glen Canyon Dam. The second objective was to extract from GCES some of the possibilities and limitations for cooperative government studies of ecological systems that must be managed for the use and protection of multiple resources. From its review of GCES Phase 1, the NRC committee concluded that the GCES program was in part handicapped by the absence of a comprehensive review of environmental studies in the Grand Canyon. As a means of ass- isting GCES in drawing together all useful information and also of soliciting

OCR for page 11
Introduction and Background 19 analysis and comment from scientists with a working knowledge of the Colorado River in the Grand Canyon, the committee sponsored a symposium in May 1990 in Santa Fe, New Mexico. The proceedings of this symposium were published along with a revised set of recommendations for GCES (NRC, 1991~. In this second set of recommendations, the committee called for a plan for long-term research and monitoring that would succeed GCES. The committee also recommended that operation of the dam be viewed more flexibly and that a more explicit ecosystem approach be used in analyzing environmental resources. In addition, it repeated its earlier recommendation that scientific expertise external to the cooperating agencies be used much more extensively. In 1989 Secretary ofthe Interior Manuel Lujan notified the BOR thatfuture operation of Glen Canyon Dam should be designed on the basis of an EIS to be completed no laterthan 1994. This requirement was later embodied in the Grand Canyon Protection Act of 1992, which states: ong-term monitoring of Glen Canyon Dam shall include any necessary research and studies to determine the effect of the Secretary's actions under section 1204 (c) on the natural, rec reational, and cultural resources of Grand Canyon National Park and Glen Canyon National Recreation Area. The secretary also directed that a second EIS be conducted of the power marketing for Glen Canyon Dam. Preparation of the operations EIS was to be directed by the BOR, and preparation of the marketing EIS was to be directed by WAPA. The secretary's decision had a profound effect on GCES and on the scope of the NRC committee's work. GCES served as the main source of information for the EIS on operations. Although GCES was not charged with actual preparation of the EIS, time and effort of the GCES team were con- sumed in providing information for the EIS team. Thus, the EIS slowed the progress of GCES. The NRC committee included review of the draft EIS as part of its work, given that the EIS was an important application of information from GCES (NRC, 1994~. The two ElSs were significant in several ways. They set a deadline for firm decisions on the mode of operation for Glen Canyon Dam. In addition, they brought about the application of GCES information to management of the dam and thus set the stage for adaptive management of dam operations. Finally, they marked the end of an era of intensive study and a transition to long-term monitoring. The GCES was complicated by a number of management and policy

OCR for page 11
20 River Resource Management in the Grand Canyon issues that required resolution prior to its termination. The first of these was design of an interim flow regime that would bridge the gap between historical operating practices and potentially new operating practices derived from the EIS Record of Decision. The interim flows are an important landmark in the history of Glen Canyon Dam because they signify the decision of the BOR to modify its operation of the dam in a significant way to protect environmental resources, atthe cost of reduced efficiency in power marketing. In evaluating interim flows, GCES scientists had the important responsibility of recom- mending operational strategies that would be the most likely to protect or optimize environmental resources over the short term. Another important addition to the central task of GCES was the design of a long-term monitoring program. The bureau concluded that the GCES team would be the best source of recommendations on long-term monitoring and elected to include a long-term monitoring plan in the operations EIS. The GCES team turned to the NRC committee for assistance in organizing a workshop on long-term monitoring. The workshop included 50 scientists chosenfortheirknowledge ofthe environmental system ofthe Grand Canyon or for their experience with long-term environmental monitoring in general. The proceedings of the workshop were given to the GCES senior scientist as a basis for design of the monitoring plan. The committee subsequently reviewed the draft monitoring plan and offered a number of suggestions and criticisms, the most important of which were lack of specificity in the plan and failure of the plan to include guidelines for administration or funding of the monitoring program. The BOR also asked the GCES team to make recommendations for studies to be completed in the event of a controlled flood flow that was tentatively scheduled for early 1994. This flood flow for 1994 was cancelled because of possible lawsuits and because there was not enough water available. An experimental flood flow was then scheduled for spring of 1995 which was cancelled again because of possible lawsuits by the upper basin states and the need for compliance with the National Environmental Protection Act (NEPA). Another experimental flood flow is tentatively scheduled for spring, 1996. Controlled floods had appeared as a component of the preliminary draft EIS and as recommendations from experts on sediment transport, who pointed out that the rebuilding of steadily eroding beaches in the canyon would require periodic high flows of relatively short duration (several days), even though such flows had been avoided in the past because they involve the loss of hydropower revenues. An abundance of water in 1993, combined with the development of a long-term operational plan, set the stage for a controlled flood. GCES was charged with designing a data collection system that would show both the effectiveness of a flood flow in rebuilding beaches and any unexpected negative effects that the flow might have on other resources in the canyon.

OCR for page 11
Introduction and Background 21 The final products of GCES include some 65 individual reports that summarize the studies of individual environmental components such as trout populations, cultural resources, and sediment transport (Figure 1.2~. The products of GCES were also initially scheduled to include synthesis of individual studies and use of the synthesis to project the effects of various operating strategies on environmental resources below Glen Canyon Dam. The synthesis was not completed as of September 1995, but the operations EIS includes preliminary synthesis based on information from GCES as of about 1993. The chapters that follow give the NRC committee's review of the GCES. While the results of the GCES are of pressing relevance to the protection of resources in the Grand Canyon, they also serve as an excellent case study of the federal government's efforts to use ecosystem science as a guide to environmental management.

OCR for page 11
22 0 a) o - I a) ~ 0 a) cry Q ~ ~ a) Ct ,~ U) a) m En LL] lo_ 0 C' 0 == 5: o.= A o Q ,~ Cal o =5 a) ~ CD ~ o o .O = a) - ~ - I: ._ CO (~ .a = a) ~ - a) en C' - C,0 o ._ o U) ~ =E o i a) Ll,! - ~ oh m a) a) ~ en Ha =5 LL '- cn ~ ._ 0 C] .~ ~:' ~-5 cn ~s _ ~ a ~= a) 0 cn a, - 0 0 C5 . . o cn 0 01 e -c cL ~n 111 - o co c c o Q c o C: CM U] ~: ii

OCR for page 11
Introduction and Background 23 REFERENCES And rews, E.D. 1991 . Sediment transport in the Colorado River Basin. Pp. 54- 74 in Colorado River Ecology and Dam Management. Washington, D.C.: National Academy Press. Bureau of Reclamation. 1993. Operation of Glen Canyon Dam Colorado River Storage Project, Arizona. Draft Environmental Impact Statement, U.S. Department of the Interior, Washington, D.C. Dawdy, D.R. 1991. Hydrology of Glen Canyon and the Grand Canyon. Pp. 40-53 in Colorado River Ecology and Dam Management. Washington, D.C.: National Acaclemy Press. Hughes, T.C. 1981. Reservoir operations. Pp. 207-225 in Colorado River Ecology and Dam Management. Washington, D.C.: National Academy Press. Ingram, H., A.D. Tarlock, and C.R. Oggins. 1991. The law and politics of the operation of Glen Canyon Dam. Pp. 10-27 in Colorado River Ecology and Dam Management. Washington, D.C.: National Academy Press. Martin, R. 1989. A Story that Stands Like a Dam: Glen Canyon and the Struggle for the Soul of the West. New York: Holt. National Research Council. 1987. River and Dam Management: A Review of the Bureau of Reclamation's Glen Canyon Environmental Studies. Washington, D.C.: National Academy Press. National Research Council. 1991. Colorado River Ecology and Dam Management. Washington, D.C.: National Academy Press. National Research Council. 1994. Review of the Draft Environmental Impact Statement on Operation of Glen Canyon Dam. Washington, D.C.: National Academy Press. Plummer, B. 1983. The Colorado River, a river for many people. Pp. 3-1 1 in Aquatic Resources Management of the Colorado River Ecosystem, D.D. Adams and V.A. I~marra, eds. Ann Arbor, Mich.: Ann Arbor Science. Powell, ~I.W. 1895. Canyons of the Colorado. Reprinted by Argosy- Antiquarian, New York, 1964. Reisner, M. 1986. Cadillac Desert: The American West and Its Disappearing Water. New York: Viking Press. Valdez and Ryel. 1995. Life history and ecology of the humpback chub (Gila cypha) in the Colorado River, Grand Canyon, Arizona. Final Report to the Bureau of Reclamation, Contract No. 0-CS-40-09110. Bio/West Report No. TR-250-08.