Integrated And Cumulative Threats To Water Availability

The following chapter of Threats to Water Availability in Canada, published by the National Water Research Institute and the Meteorological Service of Canada, defines meta-problems and outlines how they can be addressed.

Stewart J. Cohen,1 Rob de Loë,2 Alan Hamlet,3 Ross Herrington,4 Linda D. Mortsch5 and Dan Shrubsole6

  1. Environment Canada, Meteorological Service of Canada, Adaptation and Impacts Research Group, and University of British Columbia, Vancouver, BC
  2. University of Guelph, Department of Geography, Canada Research Chair in Water Management, Guelph, ON
  3. University of Washington, Department of Civil and Environmental Engineering, Seattle, WA
  4. Environment Canada, Meteorological Services of Canada, Regina, SK
  5. Environment Canada, Meteorological Service of Canada, Adaptation and Impacts Research Group, and University of Waterloo, Waterloo, ON
  6. University of Western Ontario, Department of Geography, London, ON


The institutions that have guided development of Canada’s water resources have been varied and have evolved in response to different and changing human and biophysical circumstances. Canadians have sought ways to promote development through providing additional storage of water, reducing variability of river flows, and redirecting and utilizing groundwater flows. Only recently have there been concerted efforts to reduce the demand for water. Harnessing water resources has often led to unintended impacts and problems, some of which are described in earlier chapters. Since water is connected through the hydrologic cycle, it is sometimes difficult to manage one water use without significantly affecting another. Many water resource problems can be termed “wicked” or “meta-problems” because they extend beyond the scope of a single government agency and level of government, and are associated with high levels of change, complexity, uncertainty and conflict (Mitchell, 2002). Differences of opinion over the goals to be achieved, and uncertainty and disagreement about the means to solve meta-problems are common. Problems can be chronic or acute, and may be bound or framed in technical, economic, legal, political and social ways. Proposed solutions will be multifaceted; hence information concerning human use and biophysical aspects of water and related resources will be required if decision making is to be adequately informed.

Integrated and cumulative threats to water supply are types of meta-problems. Integrated threats to the water supply are threats that emerge when combinations of stresses occur (e.g., conjunctive groundwater and surface water problems, expected changes in climate and population with associated changes in water demand, simultaneous changes in water uses, etc.). Cumulative threats refer to evolving impacts over time. These emerge slowly and evolve over long periods. The process of attempting to solve these kinds of problems will commonly involve participation of various agencies, possibly from all levels of government, the private sector, users/clients, relevant non-government organizations, and the general public. Furthermore, the problem-solving process may itself evolve over time rather than being predetermined at the outset. Climate change is a good example of a potential cumulative threat.

Previous chapters have dealt with some specific aspects of these meta-problems and have highlighted various uncertainties, complexities, conflicts and changes associated with water quantity challenges. Rather than reviewing all aspects of the problem, this chapter turns its attention to two elements:

  1. A description of how integrated and cumulative threats to water supply can develop. The case of the Columbia basin illustrates the ways in which decisions made by government agencies with relatively narrow mandates and acting independently from one another contributed to the escalation and creation of a meta-problem.
  2. Illustrative examples of agencies that have initiated mechanisms that promote broad approaches to water management. These provide a status report on several current attempts at solving meta-problems. Each agency relies on the best information available to make informed decisions, and on collaboration with other agencies, governments, stakeholders and the public.

Current Status—Recent Experiences in Managing for Integrated and Cumulative Threats

Management plans for future threats will vary within and amongst jurisdictions, and within each watershed. Watershed planning, groundwater management studies, and impact assessment procedures can help formulate decisions. In Canada, provincial governments have primary responsibility for managing natural resources, including water. The federal government has narrower, but important, responsibilities relating to areas such as fisheries, navigation, federal lands, and transboundary matters. Federal, provincial and municipal governments may collect information on natural resources and provide this information to the public. Water resource agencies may regulate or license water-use activities and charge applicable fees.

Governments at all levels have developed processes to ensure that the public interest is well served; however, no “single” perfect management arrangement exists to address and respond to integrated and cumulative problems. It can be difficult to identify a central management authority for each major watershed that could respond effectively to cumulative threats (e.g., globalization effects, climate change, technological change/risks). Meeting such challenges would require a coordinated response among many parties (e.g., hydro, irrigation, flood control, aquatic ecosystems, fisheries, navigation, municipal/domestic/industry) and jurisdictions.

Examples of integrative approaches to water management reflect the ability of institutional arrangements to address integrated and cumulative threats. We present here an overview of water problems in the Columbia River basin, followed by a description of the integrated approaches applied by the Prairie Provinces Water Board, and the Great Lakes Charter.

Example of an Integrated and Cumulative Threat—the Columbia River Basin

A case study of the historical development of the Columbia River basin, and the evolving institutional response to various issues in the basin over time, presents a useful illustration of the importance of the evolution of a cumulative threat, and the formidable challenges associated with defining appropriate problem boundaries for planning, impacts assessment, and institutional response. Figure 1 illustrates how the problem boundaries have expanded since the ratification of the Columbia River Treaty (CRT) in 1964. The CRT led to the construction of a reservoir operating system, comprised of several dams in the U.S. and Canada (e.g., Keenleyside, Duncan, Mica, Libby, etc.). The system was oriented toward transboundary aspects of winter dominant hydroelectric production and flood mitigation. Following construction of the four new storage projects authorized by the CRT, and Dworshak Dam1 (1973) in the U.S., the timing of regulated flow in the Columbia was dramatically altered. Despite far-reaching ecological implications of these changes in flow regime, ecological considerations were not within the institutional problem boundary at the time, and the CRT defined no formal, binational, coordination mechanism for maintaining instream flows for the ecosystem.

Fig. 1 Challenge of expanding water management problems: evolution of Columbia basin management issues from 1965 to present.

The completion of the Libby Dam in 1976 marked the end of the period of major dam construction in the Columbia authorized by the CRT2, and the beginning of an evolving awareness of, and institutional response to, the impacts of development. Perhaps the most far reaching of these impacts have been those relating to the Columbia's salmon fishery. While commercial fishing, dam blockage, and habitat destruction had created considerable impacts to salmon stocks in the Columbia prior to the CRT, the completion of the CRT dams and poor ocean survival from 1977 to 1995 quickly brought the salmon issue to a crisis level. Institutional response followed. The Northwest Power Planning and Conservation Act (1980) in the U.S. established the equality of hydropower and salmon in the Columbia under U.S. law, and the Northwest Power Planning Council was formed in the U.S. to attempt to establish a more equitable relationship between reservoir operations for hydropower and fish. Despite this legislation and a host of ongoing “engineering” solutions to the salmon problem (e.g., increased use of hatcheries and barging of juvenile fish to the ocean to avoid problems in the freshwater habitat), no substantive adjustments were made to the Columbia's reservoir operating policies until Endangered Species Act (ESA) listings for several salmon stocks in the late 1980s in the U.S. forced an intervention by the National Marine Fisheries Service (NMFS), which ultimately resulted in some significant changes in the Columbia's reservoir operating policies in 1995 (National Marine Fisheries Service, 1995) and again in 2000 (National Marine Fisheries Service, 2000).

  • In the 1990s institutional problem boundaries expanded markedly to include the following:
  • protection of additional salmon species in the lower basin, and the Kootenay (Kootenai) River sturgeon listed under the U.S. ESA
  • protection and restoration of riparian and instream habitat
  • increased monitoring and management for water temperature and gas content
  • increased protection of lake ecosystems in the upper basin (in conflict with U.S. instream flow needs)
  • compensation for people displaced or affected by dam construction (e.g., The Columbia Basin Trust)
  • proposed removal of four large run-of-river dams in the lower Snake River
  • impacts of climate variability and climate change
  • proposed changes to water law and water allocation practice for irrigation (e.g., water banks and water markets), and
  • changes in regional and international energy policy (e.g., deregulated energy markets).

Most of the issues listed above have emerged outside the relatively narrow institutional problem boundaries in place less than a decade ago (Bankes, 1996; Volkman, 1997; O’Neil, 1997; Miller, 2000; Cohen et al., 2000). The result is that managers and policy makers on both sides of the international border are being called upon to manage the Columbia's water resources on a more integrated basis, involving ecological, economic, political, and cultural factors within a relatively narrow framework of institutional arrangements that were never designed to encompass these diverse management concerns.

Example of Integrated Approach: Great Lakes Charter

While the Great Lakes is a large freshwater system, it is a finite system and only a small proportion of the waters are renewed annually. Increasing or new consumptive uses such as irrigation, manufacturing and industrial processes, exports (bulk water transfers and bottled water sales) as well as diversions (into and out of the Great Lakes watershed for navigation, municipal water supply and waste assimilation, hydro generation) may have adverse impacts on the sustainability of water resources in the Great Lakes region. Historically, conflicts and controversies have occurred about use and diversion of water from the Great Lakes, particularly at Chicago where the U.S. Supreme Court intervened on several occasions over matters of water quality, navigation, increasing domestic and industrial demand, and diversion for drought mitigation outside the region. Climate change may exacerbate these (Changnon and Glantz, 1996).

In 1983, the Council of Great Lakes Governors created a task force to develop an institutional framework for dealing with diversions of water from the Great Lakes; this framework led to the 1985 Great Lakes Charter. The Charter builds upon the initial intent to “preserve levels and flows” in the Boundary Waters Treaty of 1909. It also recognizes that Great Lakes waters are interconnected and should be treated as a single hydrologic system transcending basin political boundaries, and that multiple uses of the water resource, maintenance of habitat, and balanced ecosystem are interdependent. Water resources management is guided by five principles: integrity of the Great Lakes basin; cooperation between jurisdictions; protection of Great Lakes water resources; prior notice and consultation; and cooperative programs and practices. While the Charter is considered a “soft law” instrument and is not legally binding on the signatories, through consensus and cooperation it does help guide the behaviour of the eight Great Lakes states and two provinces (Saunders, 2000). Most importantly, any major new or increased diversion or consumptive use of Great Lakes basin water requires prior notification, consultation and concurrence of all affected parties. The Charter states that it is the “intent of the signatory states and provinces that diversions of basin water resources will not be allowed if individually or cumulatively they would have any significant adverse impacts on lake levels, in-basin uses and the Great Lakes ecosystem” (Council of Great Lakes Governors, 1985).

Recognizing that implementation of measures to protect the water resources of the Lakes will fall to the signatories, the Charter states that the eight states and two provinces will implement legislation to establish programs to manage and regulate diversions and consumptive uses. Ontario is an example of a jurisdiction that has addressed this commitment. The Ontario Water Taking and Transfer Regulation (Ontario Regulation 285/99), made under the Ontario Water Resources Act (Revised Statutes of Ontario 1990, Chapter O.40), requires that decisions made regarding water allocation through Permits to Take Water “shall ensure that Ontario's obligations under the Great Lakes Charter with respect to the application are complied with (Ontario Regulation 285/99, Section 4).”

A potential application of the Great Lakes Charter may arise in the context of the proposed pipeline from the Great Lakes to the Regional Municipality of Waterloo (RMOW). Pressure on sub-regional water resources (the Grand River basin) comes from urban growth. This has tested the limits of the available supply for several decades. The RMOW, currently 80% groundwater dependent, is planning for a pipeline to one of the Great Lakes by 2035. Low water levels due to recent droughts in 1997 to 1999 and 2001 to 2002 have necessitated water-use restrictions in urban areas, and have created conflicts in areas of heavy irrigation. Threats to water quality originate from agricultural activities, treated wastewater discharges, and industrial and commercial activities (Grand River Conservation Authority, 1998). Wellhead and aquifer protection planning at the local level have emerged as a priority for the Grand River, with the RMOW playing a leading role due to its early experience with contamination of the water supply of the Village of Elmira from N-nitrosodimethylamine in 1989 (Neufeld, 2000). If one is developed, and depending on which lake is the source, this project could be viewed as an interbasin transfer and undermine the intent of the Boundary Waters Treaty—to preserve levels and flows. If other communities within and adjacent to the basin had similar proposals, the cumulative effects on some economic, social and ecological activities could be significant.

In 2001, a Supplementary Agreement to the Great Lakes Charter was signed. It reiterates the commitments under the Charter but commits the Great Lakes states and provinces to prepare a basin-wide binding agreement, establish a decision-making standard for review of proposals, develop public participation, and identify decision-making and dispute-resolution mechanisms (Council of Great Lakes Governors, 2001). This mechanism might anticipate the potential problems with interbasin transfers and provide for an effective and equitable allocation of water resources between instream and withdrawal users. Developing mechanisms and procedures that effectively balance basin-wide interests and needs with regional and local ones is an emerging theme related to cumulative and integrated threats.

The Charter is an innovative example of trans-national cooperation, yet problems exist at the sub-national level (Saunders, 2000). To implement the Charter, signatories agreed to collect common water use and management data, facilitate data exchange, establish a Water Resources Management Committee, develop a Great Lakes Basin Water Resources Management Program, and coordinate research. Some aspects are not fully implemented (International Joint Commission, 2000). Deficiencies in the water use data make accurate accounting difficult. The trigger level for notification of water diversion or consumptive use projects (greater than 19 million litres per day over a 30-day period) is high; smaller projects can have cumulative impacts but are not addressed. While affected parties must be notified and consulted on diversions, they lack a veto for projects.

Example of an Integrated Approach: Prairie Provinces Water Board

Runoff from the eastern slopes of the Rocky Mountains is the major source for the larger southern rivers of the Prairie Provinces. These larger rivers flow eastward across Alberta, Saskatchewan and Manitoba to empty into the Hudson Bay. Some streams originate off the Prairies and from heights of land, such as the Cypress Hills. These streams may also flow east across provincial boundaries before joining the larger rivers or forming landlocked lakes. Ownership of the waters of a river system flowing through two or more jurisdictions can give rise to many administrative and water-use problems.

In 1948, Manitoba, Saskatchewan, Alberta and Canada agreed to establish the Prairie Provinces Water Board (PPWB) to recommend the best use of interprovincial waters in relation to associated resources in Manitoba, Saskatchewan and Alberta, and to recommend allocation of water between each province for streams flowing from one province into another.

In 1969, the four governments entered into the Master Agreement on Apportionment to provide an apportionment formula for eastward flowing interprovincial streams, to recognize the problem of water quality, and to reconstitute the PPWB to administer the Agreement. The Master Agreement was amended in 1984 to clarify apportionment arrangements for the Battle, Lodge and Middle creeks, which are international as well as interprovincial streams: in 1992 to add a Water Quality Agreement, and in 1999 to define interprovincial lakes as water courses under the Agreement.

The Master Agreement is based on the principle of equitable sharing of available water in the Prairies. The formula generally states that each province may use one half of the natural flow of water originating within its boundaries and one half of any flow entering the province. Natural flow is broadly defined as the volume of flow that would occur if a river had not been affected by human activity. The Agreement also allows comparing water quality at interprovincial boundaries to acceptable levels, and facilitates a cooperative approach for the integrated development and management of interprovincial streams and aquifers to ensure their sustainability for the benefit of the people of the Prairie Provinces.

The PPWB Secretariat performs the day-to-day work of the Board, with its office in Regina. The Secretariat, made up of Environment Canada staff, reviews and analyzes monitoring data, calculates natural flow at the boundaries, determines conformity with water quality objectives, and reports on apportionment and water quality at the interprovincial boundaries. The PPWB has three permanent committees on water quantity, water quality and groundwater to assist in technical work and to provide advice to the Board.

Environment Canada fulfills the monitoring conditions described under the Master Agreement and provides information from 75 long-term water quantity monitoring stations, 16 meteorological stations and 12 water quality monitoring sites. Other agencies provide information from an additional 13 water quantity monitoring stations. This information is used to calculate natural flows and levels of water quality parameters.

The values calculated for 14 water quantity and 12 water quality monitoring sites along the Alberta-Saskatchewan and Saskatchewan-Manitoba borders are used by the PPWB to decide whether or not requirements of the Agreement are being met. Although the Agreement applies to all eastward flowing interprovincial streams, formal apportionment calculations are only done for streams with significant water use.

Since being signed, the Master Agreement on Apportionment has allowed the equitable sharing and protection of interprovincial streams while developing a consensus approach to preventing interprovincial surface and ground water problems. The PPWB has always sought a consensus of its members, so provincial governments, the primary regulator of water supplies, have always complied with the Agreement. Therefore, the Master Agreement could be considered a model for dealing with interjurisdictional issues.

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