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Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival (2004)

Chapter: 7 Water Resources Management, Risks, and Uncertainties

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Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×

7
Water Resources Management, Risks, and Uncertainties

Decisions regarding permit applications for consumptive water withdrawals from the Columbia River involve imprecise calculations and assumptions of salmon’s physiological needs, river flows, and present and future amounts of upstream water uses. These decisions must thus consider and balance a variety of imperfectly understood risks. This chapter examines issues associated with managing these risks. It also examines challenges associated with using scientific information in decision-making applications. Part of this study includes the review of several water management scenarios (also listed in Appendix B). Comments on these scenarios are located near the end of this chapter.

RISKS AND WATER MANAGEMENT

A Simple Stream

This example assumes a stream with three users, all under the jurisdiction of one state: User A in the headwaters, User B in the stream’s middle reach, and User C in the stream’s lower reach. The average instream flow is 15 units of water. For purposes of this example, recognizing that reality is far more complex, it is assumed that salmon need a minimum of 4 units of water. Three possible variations are considered:

Variation 1: User A consumptively uses 5 units of water. After this use, 10 units remain in the stream at the top of the middle reach. User B consumptively uses 3 units of water but wants to expand use to 5 units. The state could permit User B to do so, since 5 units of water would still remain in the river, one more than the salmon “need.”

Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×

Variation 2: After the new uses contemplated in Variation 1 are implemented, User A wishes to expand use in the upper reach. The state could permit the consumptive use of 1 additional unit in the upper reach without adverse effects to salmon in the middle reach under average or normal conditions. When the upper-basin water supply is less than normal, however, users A and B will both continue their uses until the water available to salmon is exhausted, unless that water is afforded legal protection. Thereafter, User A’s junior rights will be curtailed in favor of User B’s senior downstream rights. Unless the water requirements of salmon in the middle reach have legal protection, however, the salmon will suffer adverse effects in below-average water years.

Variation 3: Now consider User C’s downstream uses that require 5 units (they could be consumptive or nonconsumptive). In a normal water year, User B must pass that much water through the middle reach. Since this “pass-through” water also benefits salmon in the middle reach, User B can still consumptively use 5 units in the Middle Reach (10-5 = 5 units “pass through” to downstream uses). An additional unit of development can occur in the headwaters or middle reach. Beyond that margin, the water needed for salmon will be reduced.

If the stream is wholly within the jurisdiction of one state, these variations can be successfully managed so long as salmon instream flow requirements have legal protection. Such protection can result from a water right or water reservation with its own priority date that is administered along with other priorities on the stream. Legal protection also can result from a regulatory program, perhaps under the Endangered Species Act or under a water quality statute that requires maintenance of a given streamflow. Without legal protection for the water necessary for salmon in the middle reach, however, increases in upstream water uses may eventually encroach upon flow levels required to sustain a salmon population(s).

Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×

A Complex Stream

Legal and Water Availability Uncertainties

A more complex situation (and more similar to that in the Columbia River basin) is considered below. Rather than a basin within a single state, the Columbia River is subject to a complex jurisdictional web. User A is no longer a single user whose uses are permitted by a single state. In the Columbia River basin, “User A” is the collective of many upstream governments and entities. Looking upstream, water is currently used in Canada, Montana, Idaho, and Wyoming, as well as Washington and Oregon. There are also potential future uses, such as potential Canadian claims under international law, equitable claims of Montana and Idaho to the waters of an interstate system, and indigenous and reserved water rights claims of upstream Indian tribes.

Water availability in the middle reach is also subject to existing and future downstream claims as well (User C in the previous example). These include claims for sufficient water for navigation, senior water rights for federal reclamation projects, other senior water rights, claims of downstream Indian tribes for instream and diversionary purposes, and equitable claims of Oregon, Nevada, and Utah to the waters they contribute to the interstate system. Other so-called federal regulatory water rights such as sufficient flows for water quality and the protection of listed species under the Endangered Species Act, impose limits on water use both upstream and downstream of the middle reach.

Whether one looks at upstream or downstream rights, present flows in the Columbia River mainstem do not necessarily accurately reflect current legal allocations. In addition to climate trends and variations, actual withdrawals may be augmented by water rights not being currently used and water rights applied for but not yet adjudicated. Although legal entitlement is supposed to be contingent on actual and continual use, water use is not always carefully monitored. Some water rights holders may go many years without diverting their full entitlement. This is important because unless full rights are extinguished for lack of use, they may emerge as significant withdrawals at some unpredictable future time. Further, even in Washington, some surface waters have not been adjudicated. Approximately 160,000

Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×

pre-1917 surface water claims and pre-1945 groundwater claims remain unadjudicated statewide, although it is uncertain how many of these claims are contiguous to the Columbia River. Approximately 100 pre-1917 claims for surface water list the Columbia River in eastern Washington as a source.

On the other side of the ledger, illegal diversions may inflate actual withdrawals from the river. The National Marine Fisheries Service 2000 Biological Opinion suggests that controlling illegal use of water at U.S. Bureau of Reclamation irrigation projects could substantially reduce streamflow depletions. This opinion was pursuant to a 1994 Inspector General’s report that detailed unauthorized uses within bureau projects, some of which are situated on the Columbia River. Although the Bureau of Reclamation is aware that unauthorized uses occur, it does not now have a dedicated program or schedule in place to address and resolve all instances of unauthorized use. The bureau has undertaken some efforts, in this realm, including geographic information system (GIS) mapping of the Columbia River Project. Onsite review may be necessary to accurately determine the extent of unauthorized uses, which would require staff and related resources. A report issued by the bureau warns that farmer resistance could make it difficult to quantify unauthorized uses and that efforts to limit unauthorized diversions must be cautious and collaborative (U.S. Bureau of Reclamation, 2000). The bottom line is that current flows of the Columbia River do not present an accurate picture of legal entitlements to withdrawals.

The Columbia River system can no longer be managed under a simple set of priorities. A legal inventory may tell only part of the story. Canada has treaty and equitable rights to the river. Other Columbia River basin states also have equitable apportionment claims. The water rights of these sovereigns, although impossible to predict, constitute “first” claims on the river. In addition to their fisheries rights, many of the basin tribes have reservations with arable land. Under federal law, many of these tribes have reserved water rights for irrigation and other “permanent homeland” purposes. The priorities of these rights may vary depending on evidence of aboriginal use, treaty entitlements, when lands were acquired, and many other factors. State-law water rights for reclamation projects and other uses in Washington and other states may not be fully developed; and, short of a general basinwide stream adjudication, it is difficult to deter-

Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×

mine how much additional water use is authorized and, if developed, whether priorities of these uses will relate back to the original dates of filing or appropriation. These legal uncertainties exist against a backdrop of variable water supplies. During normal climatic situations, precipitation may vary considerably from year to year. And, as explained in Chapter 3, possible climate warming across the basin may portend increasingly erratic patterns of streamflow and water availability.

Risk and Uncertainty Involving Endangered Species

The existence of threatened and endangered species, such as salmon and steelhead, can further complicate water management decisions. A previous National Research Council committee addressed risk assessment in the context of the Endangered Species Act (NRC, 1995). That report identified the two types of risk addressed by this statute: the risk of species extinction and the risks of potentially unnecessary expenditures of money and curtailment of resource use given the uncertainties about the risk of extinction. The report enumerated major factors that appear to influence the risk of extinction and discussed the difficulties of estimating the risks of extinction, many of which are presented in considering potential new diversions from the Columbia River. In addition, other NRC committees have examined issues of the use of risk analysis in water management and risk communication (NRC, 1996, 2000). Based on definitions and applications in those reports, this report defines risk as the probability that some undesirable event occurs, as well as the combination of that probability and the corresponding consequence of the event. Uncertainty is used to describe the lack of sureness about something.

A key risk in many situations in which species face extinction is the relatively small population size of the species. In small populations, even random demographic or environmental changes can have large consequences for species survival. Catastrophes such as drought or fires can suddenly reduce population numbers. In small populations, genetics can also be a factor as “mildly deleterious genes, previously kept at low frequency by natural selection, can rise to high frequency by change” (NRC, 1995, p. 133). The species’ ability to adapt genetically to

Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×

environmental changes is also diminished because genetic variation, the key to species’ adaptation, can be compromised by reductions in population size (ibid., pp. 134-135). The report noted, for example, that “Populations need about 1,000 individuals to maintain their genetic variation” (ibid., p. 135; the report also noted that this actual number depended on the biology of the organisms involved). Applying these findings, random demographic and genetic changes are likely not primary risk factors for the threatened and endangered salmon runs in the Columbia River. These factors are more detrimental in populations of fewer than 1,000 individuals, and the Columbia River salmon runs, although in jeopardy, are more numerous. Habitat frag-mentation is another important risk factor and, because of the many physical alterations of the Columbia River system, of greater concern to salmon survival. The report also noted that the effects of even minor detrimental changes in specific habitat areas may accumulate over time—an especially relevant observation in the context of this report’s considerations of how Columbia River water withdrawals affect salmon survival rates. As the report states:

Not enough is known about cumulative effects and threshold points…. When considering the probable effects of incremental human activities, it is reasonable to assume that additional activity means additional risk, but we rarely know whether the relationship … is linear or whether there might be critical levels of activity above which the risk of extinction increases dramatically. (p. 156).

Compounding of Uncertainties

All these legal, economic, biological, and water availability uncertainties intersect in water permitting decisions concerning the Columbia River middle reach. There are many legal and economic uncertainties regarding how much additional water will be consumptively used upstream by Canada, other states, and tribes. While downstream uses help “pull” water downstream for salmon, similar legal and economic uncertainties exist about the growth of these downstream uses. Ocean conditions

Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×

also influence levels of salmon returns to the Columbia River. Climatic uncertainties confound precise predictions of how much water will be available to use throughout the basin.

The “risk-based” nature of permitting in the Columbia River middle reach is suggested by Table 7-1. The rows of this table represent different assumptions about water availability in a given year, with high flow conditions (risk value 1) presenting lower risks to salmon and low flow conditions (risk value 3) presenting higher risks. The columns display different risk assumptions about the extent of upstream consumptive use in that year. If little additional water has been allocated for consumptive use in the upper basin, the risk to salmon in the middle reach is low (risk value 1). If much upstream allocation has occurred, the risk to salmon in the middle reach is high (risk value 3). The shaded cells in Table 7-1 indicate the products of the interaction of water availability risks and consumption risks. The darker cells suggest high risk to salmon in the middle reach of the Columbia River in circumstances of low water availability and high levels of upper basin water development (i.e., a high risk of low flows compounds the situation of having high levels of use in the upper basin).

Table 7-1 depicts risks to salmon presented by the varying relationships between river flows and upstream consumption. Similar tables could be drawn for all the other variables (e.g., temperature, habitat) that affect salmon survival. The problem for water managers is that the risk factors in such tables combine with one another. That is, the risk to salmon viability is a composite of all these individual risk factors. If managers are confident in scoring all these risk factors low (lighter-color cells), additional permits can be issued with assurance that impacts on salmon will be minimal. However, if managers score many or all the individual risk factors high (darker-color cells), additional permitting could affect salmon adversely. Perhaps an even greater challenge is that seldom are these varying risks to salmon quantified as precisely as suggested in the table. In nearly all cases, risks are only partially understood and entail some qualitative understanding and a need for professional judgment in decision making.

Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×

TABLE 7-1 Hypothetical Risks to Columbia River Salmon*

Given Flows for Specific Water Year

Levels of Upstream Consumption

 

Low (1)

Medium (2)

High (3)

Low flows (3)

Risk = L x L = 3

Risk = L x M = 6

Risk = L x H = 9

Medium flows (2)

Risk = M x L = 2

Risk = M x M = 4

Risk = M x M = 6

High flows (1)

Risk = H x L = 1

Risk = H x M = 2

Risk = H X M = 3

* Risk values range from 1 (lowest) to 9 (highest).

COLUMBIA RIVER MANAGEMENT DECISIONS

Anticipated Permitting Decisions

Under optimal conditions, a permitting agency could make confident predictions of existing and anticipated water use, especially above the reach in which additional permitting is planned. The permitting agency would also have reliable estimates of future water availability and the distribution of those flows throughout the year. Potential permitting decisions for the middle reach of the Columbia River, however, present a less than optimal situation since, from a legal perspective, existing and future upstream water uses are difficult to determine and water availability is subject to variability at various timescales. Further decreases in flows or increases in water temperature will increase the risks associated with managing water resources and salmon and are likely to reduce survival rates. The confluence of some, or all, of the many factors that threaten to reduce Columbia River flows poses serious risks for salmon, many of which are endangered. Given the current setting and likely future climatic and other trends, additional water withdrawals from the river during seasons characterized by low flows (particularly in drought years) will pose additional risks to salmon survival, which should be considered in decisions regarding potential future Columbia River withdrawals during low flows.

Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×

Interjurisdictional Cooperation

Many of the risks that confound permitting decisions in the middle reach of the Columbia River result from upstream uncertainties that Washington State has little control over. An inventory or model of water rights on the Columbia River cannot be reliably created because the extent of many of the largest rights cannot be determined until adjudications, other litigation, or settlements are completed. An interjurisdictional water organization is one means that could help better manage or even reduce uncertainties. Such an organization could provide a forum for improving information and assessing the consequences of major management actions on the Columbia, as well as providing a broader setting for discussion and learning. Such an organization should include the basin sovereigns—the Canadian and U.S. governments, U.S. basin states and Canadian provinces, and Indian tribes. The body should establish a means to incorporate and discuss scientific input. This body should establish a threshold(s) volume of proposed new withdrawals that would be likely to concern more than one government. For instance, any proposed new use of water of more than an agreed-on amount could be considered presumptively suspect and would have to be referred to the interjurisdictional organization for deliberation. The organization’s decision rules might require hearings and a complete record on the basin consequences before the project could continue. The rules might also require the organization’s approval before the permit could be issued.

Incremental Actions and Adaptive Management

Consideration of water permit applications in the State of Washington takes place in a contentious and turbulent science and policy context. The body of scientific knowledge of Columbia River salmon is complex and incomplete, and there are competing scientific theories regarding some of the relationships between salmon and environmental variables. There are also many decision makers with differing goals, a situation noted in a 1989 article on Columbia River management, “A … problem is the large number of hands on the steering wheel” (Lee, 1989).

The setting of multiple political jurisdictions, competing

Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×

stakeholder groups, endangered species, a complex ecosystem, and a large but imperfect body of scientific knowledge is not unique to the Columbia River and in fact is characteristic of many major U.S. river systems. In an effort to implement management regimes that help reduce stakeholder disputes and that strike a more amenable balance between legal obligations and authorizations, many management agencies in the United States (and abroad) are exploring the prospects of “adaptive management” strategies. Adaptive management has its foundations in many different fields, but its theories and concepts were formalized by ecological scientists in the 1970s (Holling, 1978; see also Gunderson et al., 1995: Gunderson, 1999; Lee, 1993, 1999; Walters, 1986). Elements of adaptive strategies include:

  • An explicit recognition of uncertainty and the need to learn more about coupled ecological-social systems in order to enhance learning and reduce uncertainties;

  • Recognition that adaptive management entails a process, not a final answer or a series of management “endpoints” to be rigidly pursued;

  • Learning while doing. Adaptive management does not postpone management actions until “enough” information is available (Lee, 1999). It seeks management actions that can be reversed in light of new information and actions that can help improve ecological understanding while also meeting economic and environmental needs. Adaptive management is not “trial-and-error” management, but rather entails carefully designed management actions, with purposeful monitoring of outcomes in a structured learning process;

  • Flexible, incremental actions that enhance learning and that seek to avoid catastrophic error;

  • A means of gathering information on environmental and economic outcomes of management decisions;

  • A vision or a model of the ecosystem that is being managed (Walters, 1986). This vision or model provides a baseline for defining surprises. Surprises and other new information help increase knowledge and understanding of the system (Lee, 1999);

  • Organizations that can learn from new information and policies that can be adjusted in light of new information;

Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×
  • A collaborative structure for stakeholder participation. Participants should be willing to negotiate, try a variety of temporary measures, and evaluate promising measures before they are implemented. Adaptive management does not seek to eliminate differences of opinion or conflict but rather to provide a framework for their discussion. Adaptive management is not a substitute for willingness to compromise and give-and-take, however, and unless stakeholders are willing to agree on basic questions or lines of inquiry to be pursued by an adaptive approach, formal adaptive management will be inappropriate. Well-managed conflict can be a resource for new ideas and approaches and mutual learning, but one cannot manage adaptively in the absence of stakeholder flexibility (Gunderson, 1999).

An adaptive management approach would encourage Columbia River basin entities to move forward incrementally and try a variety of approaches for better understanding and managing risks and uncertainties. Decisions and policies should promote flexibility while their outcomes are being evaluated and better understood. A broad range of stakeholder groups from across the Columbia River basin should be engaged in crafting these decisions.

A variety of approaches to meet water demands in the middle reach might be explored. Chapter 6 identified several economics based alternatives, such as cost-shared water conservation improvements, reallocating existing uses, water banks, and water transfers. Most or all of these types of measures could be implemented incrementally and could be amenable to change as new economic and environmental information is gained. Adaptive management aims to yield better information about ecological, economic, and policy conditions, reduce uncertainties, and engage participants in a collaborative learning process aimed at solving complex problems, such as Columbia River management. The following section discusses the use of scientific information in decision-making contexts that are laden with uncertainty.

Science and Decision Making

A vast amount of scientific research on Columbia River salmon has been conducted over a period of several decades.

Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×

The resulting body of knowledge provides a broad understanding of salmon life cycles and histories, physiological characteristics of salmon, and environmental variables important to salmon survival. As explained in Chapter 4 and in other sections of this report, Columbia River salmon inhabit and travel through extensive oceanic and riverine systems during their life cycles. The size and the complexity of these systems, and the biological complexities of salmon, frustrate attempts to understand any of these factors with high precision and certainty. Substantial resources have been devoted to investigating Columbia River salmon, and today these fish species are one of the most intensively studied in the United States, if not the world. Although scientific understanding of the salmon has improved over the decades, perfect understanding of all factors and relationships that affect salmon life cycles is beyond current and foreseeable future scientific means.

More precise scientific information regarding salmon behavior, environmental influences, and rates of survival could, over time, no doubt be obtained. However, significant resources are now being devoted to this pursuit, as federal and state scientists and scientists from universities and regional consultancies are involved in extensive salmon research programs. One task pursued in this study concerned the identification of knowledge “gaps” and “scientific information” needed to develop comprehensive strategies for recovering and sustaining listed species and managing water resources to meet human needs (see Chapter 1). This task, however, presupposes that sound management strategies can be devised only when scientific “gaps” are filled and that it is possible to determine a priori the scientific information that will lead to better management decisions. Such suppositions do not reflect contemporary natural resources management realities and the relationships between scientific information and decision making processes.

Identifying the additional scientific information that will prove useful for management is not strictly an issue of scientific inquiry but also a matter of policy-making processes. Scientists are often expected to provide specific answers for use in decisionmaking and policy making. This may place an undue burden on scientists, however, especially given the uncertainties and risks that revolve around such issues as Columbia River salmon. Science is a key component in these decisions. But rather than

Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×

looking to science to provide information in strictly a one-way direction, decision makers should collaborate with scientists in a two-way process in which management actions are taken in the face of some inevitable uncertainties, with an eye to learning more about the system(s) at hand. Progress toward “comprehensive” management cannot be accomplished through scientific inquiry alone, but rather requires stakeholders and management agencies to work with scientists in a collaborative learning process, such as that framed by adaptive management principles. As stated, Columbia River salmon management is an exceedingly complex public policy and science issue. The creation of “comprehensive” strategies that reduce tensions, protect and enhance salmon, and respond to shifting human needs will likely require an approach that mirrors these complexities, as suggested in the following passage by Lee (1989):

Sustainable development of the Columbia River basin requires managing an ecosystem the size of France. If there is to be a sustainable Columbia, it will be a place governed by rules that approach the complexity of ecological interaction.

In cases where there are sharp conflicts and differences of opinion, management agencies may understandably be reluctant to take decisive actions in the face of uncertainty. Such a stance, however, may contribute to the buildup of tensions among stakeholders. In these settings an adaptive approach may be useful. Adaptive management does not wait until “enough” information is available but recognizes that gaps are inevitable, that data collection is expensive and time consuming, and that there are sometimes problems requiring decisive actions in the face of limited information. The approach seeks to create flexible management regimes through a collaborative science and management process. Maintaining flexibility of management decisions to the maximum extent possible is essential. Additional scientific research on Columbia River salmon should continue. Better information on flow-survival relationships, for example, can reduce uncertainties and contribute to better management decisions. Scientific inquiry on the salmon should be allied with policy making and stakeholder participation in an iterative, interactive process. Adaptive management can help participants better

Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×

understand the ecosystem. However, it requires willingness among participants to find common ground and a political will to act in the face of uncertainties.

Adaptive management is not a foreign concept in the Pacific Northwest. The Northwest Power and Conservation Council has sought to manage Columbia River fish and wildlife resources under an adaptive management paradigm. The first serious attempt at implementing adaptive management principles began in 1986, and the process has proceeded with a variety of initiatives (Lee and Lawrence, 1986; Volkman and McConnaha, 1993). Although adaptive management holds promise for improving understanding of flow-survival relationships in the Columbia River, the political setting is highly contentious, economic interests and values are substantial, and management responsibilities are dispersed among many entities. Its implementation may also be inhibited by the Endangered Species Act, as the adaptive management paradigm of accepting risks and occasional mistakes as part of a learning process runs counter to the ESA’s aversion to risks. Management actions aimed at helping improve understanding of flow-survival relationships may indeed, as Volkman and McConnaha (1993) have asserted, “kick off a new round of battles.” There can be no denying the political challenges and scientific complexities that attend adaptive management principles. But the complexities of managing Columbia River flows and salmon defy simple solutions and will likely require a management paradigm of similar complexity. Although stakeholders may currently share little common ground, it is important to explore innovative ways to improve on the current management regime. Although it does not represent a panacea, adaptive management offers a systematic, collaborative learning and management process as an alternative to allowing decisions to be made through court litigation and decrees.

THE MANAGEMENT SCENARIOS

The Washington State Department of Ecology provided five management scenarios for evaluation within this study under item 5 of the Statement of Task (“Evaluate the effects of proposed management criteria, specific diversion quantities, and specific features of potential water management alternatives”;

Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×

see Chapter 1). The scenarios as provided are given in Appendix B, but because aspects of the scenarios included many details (and are not entirely transparent), they are paraphrased below.

Scenario 1

In this scenario (as in all the scenarios), it is assumed that water can be used between the Canadian border and Bonneville Dam. New permits would be issued to water users in Washington over a 20-year window (the start date is not specified) up to a total of 1 million acre-feet. Of that total, 220,000 would be allocated to the Columbia Basin Project. In addition to the million acre-feet made available to Washington State users, 427,000 acre-feet of instream flow from the Snake River would be “legally recognized throughout the Washington State reaches of the Snake and Columbia Rivers” and “600,000 acre-feet would be recognized as necessary to meet the water resource needs of the state of Oregon.”

This scenario implies that about 1,600,000 acre-feet would be used for out-of-stream uses (1 million in Washington and 600,000 in Oregon) and 427,000 would be devoted to instream flow. In addition, permits that currently are interruptible when streamflow reaches a predetermined level could be converted to uninterruptible status if the owner demonstrates “that current water use conforms to state-of-the-art water use efficiency practices.” “Uninterruptible water rights” are pre-1980 state law water rights that have priority over main stem instream flow rights established in 1980. Other pre-1980 water rights based on federal law also have priority over these instream flow rights. “Interruptible water rights” are post-1980 state law water rights that, under certain low flow conditions, may be curtailed to protect mainstem instream flow rights. Additional uninterruptible water rights that would not be curtailed under low flow conditions to protect mainstem instream flow rights are proposed.

All new water rights issued would also require state-of-the-art efficiency and would be metered. The Department of Ecology would periodically assess the management program and use scientific information to accommodate changes in knowledge, with formal reevaluations at years 10 and 20. Finally, the department would seek partners to establish a “functioning water

Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×

market or ‘water bank’ for the mainstem of the Columbia River to facilitate a more efficient allocation of existing water resources in the basin.”

Scenario 2

Scenario 2 is similar to Scenario 1, with the following differences:

1. All new permits and previously interruptible rights converted to uninterruptible status would be charged $10 per acre-foot per year to support additional efforts toward “salmon health and recovery.” The proceeds would be used to acquire water for instream flow in low-water years and to make habitat improvements in the mainstem and tributaries. The money might also be used to explore the development of storage projects (these storage projects are not described in detail. Because new storage facilities on the Columbia River mainstem are not a viable option, the implication is that additional storage would be gained by new dams on tributaries; by the creation of new reservoirs to be filled by water from the Columbia River; or other methods, all of which would require additional water withdrawals from the Columbia River mainstem).

2. Of the new permits totaling up to a million acre-feet allocated to users in Washington, 300,000 acre-feet would not be issued until existing users had demonstrated that “conservation investments were in place for a majority of users on the mainstem.”

Scenario 3

Scenario 3 is identical to Scenario 2 except that the charge for new permits and for changing interruptible permits to uninterruptible status would be $20 per acre-foot per year. In addition, the Department of Ecology would provide financial support for new conservation measures.

Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×

Scenario 4

This scenario would not allow any new water to be removed from the Columbia River for out-of-stream use by Washington users. New water rights would require “direct mitigation in the mainstem of the Columbia River.” All new water rights would require offset water to be obtained through water-right changes and transfers, conservation, or use of new storage. Existing interruptible water rights could be converted to uninterruptible status by payment of $30 per acre-foot per year. The money so obtained would be used to acquire water rights to benefit salmon populations.

Scenario 5

This scenario assumes “that the current existing rule governing water resources of the Columbia River” would continue. The current rule includes a moratorium on all new permits, however, and this scenario allows for new permits. Each new permit would be issued only after consultation with fish and fishery managers (e.g., Washington Department of Fish and Wildlife, tribes, NOAA Fisheries) and whether and to what degree mitigation would be required would be decided for each permit individually as a result of the consultation with fish and fishery managers. The upper limit, if any, of the total new water permits that could be issued is not specified.

Evaluation and Commentary

In general, the adoption of concepts related to adaptive management, such as periodic review and adjustment of the program and monitoring, and market-based conservation strategies such as conservation, the use of water markets (or “banks”), and charging for water rights, is commendable. As presented in these scenarios, however, those programs are discussed at only a general level, which precluded deeper investigation and more detailed comments.

A pervasive aspect of the scenarios is the lack of a comprehensive basinwide assessment of water uses and needs as a con-

Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×

text for evaluating permit applications. Small (relative to the flows of the Columbia River) withdrawal and permitted volumes will have only small, if not minuscule, effects on the water budget of the basin as a whole. All water uses accumulate, however, both in Washington and elsewhere along the mainstem, as well as the along tributary streams. If future demands for water increase (which seems highly likely given recent and projected demographic and economic trends), the accumulation of risks to salmon survival will be all the greater (given the variety of risks that affect salmon survival, assigning precise and credible levels of risk to changes in flows and temperature is extremely difficult). These effects would be magnified by reductions in low flow that could attend prospective climate warming as well as during periodic unfavorable ocean conditions. The lack of a comprehensive basinwide management structure hampers the ability to make comprehensive judgments (both in time and over space), and it supports this report’s recommendation for creating a basinwide framework for coordinating water use data and strategies.

Conversion of interruptible to uninterruptible water rights (Scenarios 1-4). Conversion of interruptible water rights to uninterruptible status makes adaptive responses more difficult. Interruptible water rights are interruptible so that at times of scarcity, instream flows can be protected. Making any out-of-stream right uninterruptible reduces flexibility to retain water in the river when salmon need it most—during periods of high demand and low flows.

The conversion of water rights to uninterruptible status will decrease flexibility of the system during critical periods of low flows and comparatively high water temperatures. Conversions to uninterruptible rights during these critical periods are not recommended.

Revaluation at 10 and 20 years (Scenarios 1-3). The idea of reevaluating the scenarios periodically is excellent. For this reevaluation to be meaningful, however, the program needs to be designed so that any aspect of it could be undone (reversed) if the evaluation calls for such a reversal. No evidence is provided of any such reversibility. Instead, the result will be decreasing reversibility by allowing for some interruptible water

Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×

rights to become uninterruptible. In some cases, more frequent reevaluations might be necessary. In addition, criteria for assessing the state of the art of efficiency measures are not described, and the responsibility for making that evaluation is not specified. There also is no requirement for periodic reevaluation to take advantage of improvements in water use technologies and innovations.

Monitoring and metering (Scenarios 1-3). Monitoring for compliance with standards and metering are excellent ideas and could be accomplished consistent with this report’s recommendation for comprehensive basinwide water management. Such efforts will require resources, however, and an estimate(s) of the budget and personnel required to perform such monitoring would thus be useful.

Charge for water rights (Scenarios 2-4). The disadvantages of uninterruptible water permits were considered in this study, and it was concluded that allowing new uninterruptible permits to come into existence, either through conversion or de novo, would decrease the ability of water organizations to manage risks attached to decisions such as the granting of water use permits.

Charges for water rights in this scenario appear to be arbitrarily selected and out of proportion to the probable costs of mitigation and the value of water to the users. For example, the scenarios specify charges of $10 to $30 per acre-foot per year to be used (among other things) to acquire mitigation water in low-water years. This scenario thus proposes increasing the priority of a water permit for $10 to $30 per acre-foot per year and using the money to buy water for what could be several times that amount.

Water markets (Scenarios 1-4 and perhaps 5). As discussed in Chapter 6, water markets, water banks, and other such market-based mechanisms offer potential improvements over existing systems of water allocation. However, restricting markets only to the Columbia River’s mainstem, and only to Washington, is narrowly construed. The Department of Ecology already allows for 600,000 acre-feet per year to be used by Oregon in its assumptions, but no allowances are made for uses by Idaho,

Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×

Montana, or British Columbia or by tribes. Efforts toward developing water markets should be complemented with efforts to evaluate third-party effects and to design proposals for compensating users indirectly harmed in water rights transfers.

Structural storage measures (Scenarios 2-4 and perhaps 5). A lack of specificity in this scenario inhibits the ability to comment extensively on it. It implies that tributaries are to be used for additional storage (which may have negative consequences for salmon), but the habitat and condition of tributaries are of critical importance for Columbia River water quality and for survival of salmon that use the river. Tributaries should thus be considered for protection and mitigation as well.

Scenario 5. This scenario is not clearly specified. It is not a “no action” scenario, which would entail leaving in place the current moratorium on new permits. Although the idea of consultation with fishery managers is good, no mention is made of criteria for the evaluation, how the results of the evaluation might be enforced, who decides how much mitigation is needed, and what, if any, limits might be placed on new permits.

“Mitigation” measures are suggested in most of the management scenarios. Although the idea of “mitigating” impacts is attractive, the reality of most mitigation measures is that they are not well coordinated; that is, a management agency may attempt to offset harmful impacts of water withdrawals in one part of a river system with mitigation measures (e.g., ecosystem restoration) elsewhere. The ultimate outcomes of such varying actions, however, are difficult to accurately predict, measure, and compare (if indeed they are ever measured and meaningfully compared, which they often are not), thus making it difficult to determine if “mitigation” was actually achieved.

SUMMARY

Columbia River basin water management decisions entail varying degrees of risk to salmon survival. These risks are a function of both the magnitude and the timing of management actions, such as water withdrawals. For example, additional wa-

Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×

ter withdrawals during low-demand periods pose smaller degrees of risk than similar withdrawals during periods of high demand. Decisions are confounded because levels of risk are often understood only on a broad qualitative level. Not only are key variables typically unquantified to a high degree of accuracy, the nature of interactions between key variables is often poorly understood. Some decisions may thus have only limited effects and be made well within a given range of tolerance, while some may result in critical thresholds being exceeded, without a clear understanding of these different impacts.

In this context of uncertainty and varying degrees of risk, it is important that management and policy decisions promote flexibility, and even an appropriate degree of reversibility, in the event of future unforeseen and dramatic consequences. Examples of means by which risks might be managed include organizational learning strategies (which could employ ex post evaluations to learn from successes and failures), interjurisdictional cooperation (which would encourage entities to communicate to ensure that potential gains possible through innovative strategies are not foregone because such strategies are not being employed across an entire watershed), and incremental actions (examples of which include smaller-scale, short-term, and reversible policies). Adaptive management is a strategy that integrates many of these examples. It is not a new concept in managing Columbia River basin fishery resources, and experience and successes with the concept to date—in the Columbia and elsewhere—are limited. The concept does not represent a neat and easy solution to managing the basin’s fisheries and water resources, and some may be quick to dismiss it because of its complexity or difficulties in implementation. It should be kept in mind, though, that the exceptional complexity of Columbia River salmon management is likely to entail a similarly complex management framework is to be sustainable and equitable. More scientific information on salmon will not necessarily lead to the resolution of disputes or to better management decisions. Sound, comprehensive management strategies for Columbia River salmon will depend not only on science but also on a willingness of elected and duly appointed leaders and managers to take actions in the face of uncertainties.

Sound management strategies will also require a process in which managers and elected officials help frame scientific inves-

Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×

tigations and inquiry. The scientific knowledge of Columbia River salmon, while as extensive as for any other fish species in the world, is still imperfect. Improvements in salmon habitat and return rates will require a willingness to use existing scientific knowledge to address some of the factors that scientific research suggests have led to their declines. A process in which scientists monitor outcomes of management actions and provide feedback to stakeholders and decision makers, who then adjust management actions accordingly will be instrumental in helping understand how additional scientific research can best support management decisions. This process is generally referred to as adaptive management.

The management scenarios prepared in connection with this study contain some elements that would promote organizational flexibility and have some commonalities with adaptive management strategies that are being used across the United States and in other parts of the world. Although programs such as water banks, water markets, incentives for water conservation, and better metering of water use were presented only very generally and therefore could not be evaluated in greater detail, they tend to support greater water management flexibility and merit careful consideration. Such efforts could meet with resistance from users who have little to no incentive to implement them. The situation calls for creative programs that provide incentives for water users to decrease uses or that identify alternative sources of water supplies.

The State of Washington must consider several variables in making decisions and trade-offs regarding water withdrawal permit applications and the protection of salmon populations. Those variables, which include flows, temperature, and salmon’s biological and migratory features, are only imperfectly understood and interact in complex ways. Scientific information can reduce uncertainties, but rarely can such uncertainties be eliminated, especially with regard to issues as complex as Columbia River salmon management. In such settings, decision makers must exercise some degree of professional judgment in balancing a variety of risks and uncertainties. Given the uncertainty of outcomes of these types of decisions, it is important to promote flexible decision-making regimens that can be adjusted as new knowledge is gained.

As this report has discussed, Columbia River salmon are to-

Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×

day at a critical point. The basin’s salmon populations have long been in a steady decline, and scientific evidence demonstrates that environmental thresholds important to salmon, such as water temperature, are being reached or in some cases exceeded. Salmon are especially imperiled during critical periods of low flows, high demand, and higher temperatures. The risks involved in this context include additional reductions of salmon populations, extinctions, and violations of the Endangered Species Act, as well as risks to other users of the system—such as irrigation farmers—whose water demands may conflict with instream flows needed for salmon and aquatic habitat.

The ultimate decision as to whether to issue additional water withdrawal permits from the Columbia River and nearby areas is one to be resolved by duly elected officials and their appointees in the public policy arena. But in this setting of high risk and uncertainty, if additional permits are issued, they should be issued within a framework that seeks to increase the flexibility of water management systems and organizations. Efforts to enhance flexibility are especially critical given that so many social and physical trends in the Columbia River basin—such as potential additional water claims from tribal lands and other upstream areas, human population growth, and possible climate warming—point to possible reduced water supplies during critical periods and increased risks associated with salmon management. Decisions regarding the issue of additional water withdrawal permits are matters of public policy, but if additional permits are issued, they should include specific conditions that allow withdrawals to be discontinued during critical periods. Allowing for additional withdrawals during the critical periods of high demand, low flows, and comparatively high water temperatures identified in this report would increase the risks to survivability to listed salmon stocks and would reduce management flexibility during these periods.

Water permitting decisions made by the State of Washington, as well as by other basin entities, are made with little consideration or obligations of their upstream or downstream implications. This fragmented decision-making basis is a barrier to better water management and a barrier to a more comprehensive and coordinated approach for managing the risks and uncertainties that attend Columbia River salmon management. The Northwest Power and Conservation Council and its predecessor

Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×

organization, the Northwest Power Planning Council, have served as key entities for promoting cooperative basinwide Columbia River management for over 20 years. The council has accomplished many good things, and adding a responsibility to consider water permitting decisions to its mandate may seem consistent with its natural resources management duties. But trying to integrate these functions in an existing entity could entail complications and drawbacks. A basinwide forum for considering water withdrawal permit applications above a given threshold would provide regional consideration of the systemwide implications of a proposed diversion. This forum need not entail anything binding other than an obligation to refer the applications. At a minimum, proposed diversions would be subjected to professional and public scrutiny, magnitude of risk, possibilities of mitigation, and systemwide equities. A basinwide forum for considering withdrawal permit applications would enhance unified water management across the Columbia River basin. The State of Washington and other basin jurisdictions should create a joint forum for documenting and discussing environmental and other consequences of proposed diversions that exceed a specified threshold.

Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×
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×
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×
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Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×
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×
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×
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Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×
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×
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Suggested Citation:"7 Water Resources Management, Risks, and Uncertainties." National Research Council. 2004. Managing the Columbia River: Instream Flows, Water Withdrawals, and Salmon Survival. Washington, DC: The National Academies Press. doi: 10.17226/10962.
×
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×
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×
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×
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×
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×
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×
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Flows of the Columbia River, although modified substantially during the twentieth century, still vary considerably between seasons and between years. Lowest flows tend to occur during summer months when demand for irrigation water is at its highest and when water temperatures are greatest. These periods of low flows, high demand, and high temperature are critical periods for juvenile salmon migrating downstream through the Columbia River hydropower system.

Although impacts on salmon of any individual water withdrawal may be small, the cumulative effects of numerous withdrawals will affect Columbia River flows and would pose increased risks to salmon survival. The body of scientific knowledge explaining salmon migratory behavior and physiology is substantial, but imperfect, and decision makers should acknowledge this and be willing to take action in the face of uncertainties.

In order to provide a more comprehensive water permitting process, the State of Washington, Canada, other basin states, and tribal groups should establish a basin-wide forum to consider future water withdrawal application permits. If the State of Washington issues additional permits for water withdrawals from the Columbia River, those permits should contain provisions that allow withdrawals to be curtailed during critical high-demand periods.

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