"Water managers are beginning to consider adapting to climate change...[however], the extent of adaptation by many water managers is uncertain." ⁽⁵⁾

Several studies indicate that managers are generally complacent toward the impacts of climate change.^{(36, 39)} In a survey of American water resource stakeholder organizations, no groups indicated the intention to conduct future work regarding climate change, and all ranked the level of attention given to climate change as low.⁽⁴⁰⁾ This may be because managers generally believe that the tools currently used to deal with risk and uncertainty will be sufficient for dealing with any increased variability induced by climate change. Another important factor could be the lack of standards for incorporating climate change into design decisions. The reactive, rather than proactive, nature of water management may also play a role.

Box 3: Commonly recommended adaptation options ⁽²¹⁾

There are, however, exceptions to these general trends. For example, water managers in the Grand River basin of southwestern Ontario have begun to develop contingency plans for future droughts,⁽⁴¹⁾ and a series of workshops has been held to evaluate decision analysis methods for dealing with shifting Lake Erie water levels under climate change.⁽⁴²⁾ These initiatives contradict the often-cited opinion that climate change will have minimal influence on water management operations until there is better information regarding the timing and nature of the projected changes. Researchers point out that the scientific uncertainty associated with climate change is not very different than the other sources of uncertainty that water managers are trained to consider, such as population growth and economic activity.⁽⁴³⁾ Therefore, uncertainty should not preclude the inclusion of climate change as part of an integrated risk management strategy.

Structural Adaptations

In contemplating structural adaptations, one should consider whether the system will be capable of dealing with the projected hydrological changes, as well as the economic, social and ecological costs of the adaptation.

Physical infrastructure, such as dams, weirs and drainage canals, has traditionally served as one of the most important adaptations for water management in Canada. There are conflicting opinions, however, on the potential of building new structures for climate change adaptation. Given the substantive environmental, economic and social costs associated with these structures, many experts advocate avoiding or postponing the construction of large-scale infrastructure until there is greater certainty regarding the magnitude of expected hydrological changes. On the other side of the coin is the fact that water infrastructure improves the flexibility of management operations, and increases a system's capacity to buffer the effects of hydrological variability.⁽⁵⁾ In the Peace River, for example, stream regulation will allow operators to potentially offset the effects of climate change on freeze-up dates by reducing winter releases.⁽⁴⁴⁾ Similarly, communities in the southern Prairies can use small-scale water infrastructure to increase water storage through snow management, and reduce regional vulnerability to drought.⁽⁴⁵⁾

Most existing water management plans, as well as water-supply and -drainage systems, are based upon historic climatic and hydrological records, and assume that the future will resemble the past. Although these systems should be sufficient to handle most changes in mean conditions associated with climate change over the next couple of decades, management problems are likely to arise if there is an increase in climate variability and the occurrence of extreme events. Case studies in Ontario indicate that increases in the intensity of precipitation events have the potential to increase future drainage infrastructure costs and decrease the level of service provided by existing systems (Box 4).

Box 4: How vulnerable is our infrastructure?⁽⁴⁶⁾

Several studies suggest that the design of water management systems should focus on thresholds, such as the point at which the storage capacity of a reservoir is exceeded, rather than mean conditions (e.g., references 47, 48). Thresholds can induce nonlinear and therefore less predictable responses to climatic change, which would significantly stress the adaptive capacity of water resource systems.⁽⁴³⁾

In many cases, modification of existing infrastructure operations, rather than the introduction of new structures, will be an effective adaptation option.⁽⁴⁹⁾ For example, models indicate that the Grand River basin will be able to adapt to all but the most severe climate change scenarios through modifications in operating procedures and increases in reservoir capacity.⁽⁵⁰⁾ A drainage infrastructure study of North Vancouver suggests that the system can be adapted to more intense rainfall events by gradually upgrading key sections of pipe during routine, scheduled infrastructure maintenance.⁽⁵¹⁾ Adaptations such as these can be incorporated into long-term water management planning.

Institutional Adaptations and Considerations

"The ability to adapt to climate variability and climate change is affected by a range of institutional, technological, and cultural features at the international, national, regional, and local levels, in addition to specific dimensions of the change being experienced." ⁽⁵⁾

Demand management involves reducing water demands through water conservation initiatives and improved water use efficiency. Demand management is considered to be an effective, and environmentally and economically sustainable, adaptation option. As a result, programs based on water conservation and full water costing are being increasingly used in the municipal sector. In the Grand River basin, for example, municipalities have begun to develop programs to make water use, storage and distribution more efficient. At the same time, however, many municipalities are unable to adopt demand management programs due to insufficient legal or institutional provisions.⁽⁴¹⁾ The lack of public awareness of the need for water conservation and avoidance of wasteful practices is also an obstacle. Some other factors that affect a community's ability to adapt are outlined in Box 5.

Box 5: What affects a community's capacity to adapt?⁽⁵²⁾

Community water conservation initiatives can be extremely successful at reducing water demands and minimizing the impacts of climate change on regional water supplies.⁽⁵³⁾ In a study of 65 Canadian municipalities, 63 were found to have already undertaken water conservation initiatives.⁽⁵⁴⁾ Similarly, most rural property owners surveyed in Ontario had practiced some form of water conservation, such as shortening shower times and reducing water waste in homes.⁽⁹⁾ Factors that influenced the adoption of conservation methods included program awareness and participation, level of formal education, and anticipation of future water shortages. A successful community approach to water management problems was documented for North Pender Island, British Columbia. ⁽⁵⁵⁾ Water management on the island is the responsibility of five elected trustees who oversee the water use act, which specifies volume allocations per household and the acceptable and unacceptable uses of the community's water supply. Failure to comply with the water act results first in warnings, then potential disconnection from the town's water supply.

The institutional capacity of the community or system is key in implementing effective adaptation. In Canada, introducing adaptation measures can be challenging, simply due to the fact that many different levels of government administer water management activities. Even within one level of government, several separate agencies are often involved in water legislation.⁽⁴⁶⁾ Clear definition of the roles and responsibilities of each agency involved is an important first step in building adaptive capacity,⁽⁵²⁾ as is the development of mechanisms to foster interagency collaboration (e.g., the Canadian Framework for Collaboration on Groundwater). Another key requirement is the willingness of the water management agencies to provide appropriate assistance to communities in support of adaptation implementation. ⁽⁵²⁾ The community's perceptions of the different adaptation options are also important (Box 6).

Box 6: Perceptions of adaptation options⁽⁵⁶⁾

Focus group interviews in the Okanagan Valley revealed that structural changes (e.g., dams) and social measures (e.g., buying out water licences) were adaptation options preferred by these small groups to address water shortages in that region. Structural adaptations designed to intervene and prevent the impacts of climate change, such as dams and snow making, were especially favoured. The focus groups were also able to identify the implications of different adaptation choices (e.g., the high economic and environmental costs of dams). Overall, the interview process revealed a strong stakeholder interest in climate change adaptation and the need for continuing dialogue.

Although institutional changes represent an important adaptation option in water resource management, it must be recognized that some current legislation may also present barriers to future adaptation. For example, the Niagara River Treaty may restrict the ability of power utilities to adapt to low flow conditions, as the treaty apportions water for hydroelectric power generation and the preservation of Niagara Falls scenery.⁽⁴³⁾ Another example is the Boundary Waters Treaty of 1909, which determines the priority of interests in the Great Lakes (e.g., domestic and sanitary purposes first, then navigation, and then power and irrigation) and does not recognize environmental, recreational or riparian property interests.⁽⁴³⁾ However, the Great Lakes Water Quality Agreement, signed in 1978, does strive to protect physical, chemical and biological integrity in the Great Lakes basin.⁽¹⁴⁾

Economics, pricing and markets are fundamental mechanisms for balancing supply and demand. In the future, water demands may be increasingly controlled through pricing mechanisms, as has been seen in the Grand River basin over recent years.⁽⁵⁷⁾ Although increasing the cost of water would act as an incentive to limit use, there are still many issues that need to be addressed, including an improved understanding of the environmental justice and equity consequences of water pricing.⁽³⁹⁾

Diminishing water supplies are expected to increase competition and conflict over water and increase its value.⁽⁴¹⁾ Resolving these issues may sometimes involve changing current policies and legislation. At present, most water laws do not take climate change into account, and would therefore be challenged by the projected impacts on water resources. For example, transboundary water agreements may require updating and careful consideration must be given to potential changes in flow regimes and levels.⁽⁵⁸⁾ Water transfers, which are becoming increasingly important mechanisms for water management in some parts of the world, often generate new problems of their own. For example, the transfer of water between two parties often impacts a third, uninvolved party, such as a downstream water user. Policy mechanisms capable of taking these third parties into account are necessary.

Within the Great Lakes basin, significant supply-demand mismatches and water apportionment issues are expected under most climate change scenarios.⁽⁵⁹⁾ Although the traditional cooperation between legal groups involved in such conflicts has been impressive, there is no fully consistent approach to water law and policy, and the historic success would likely to be challenged by the impacts of climate change.⁽⁶⁰⁾ International laws must also evolve to avoid future conflict, as few of them allow for the possible impacts of climate change.