Adaptations to Sustain High‐Quality Freshwater Supplies in Response to Climate Change
As defined by the Intergovernmental Panel on Climate Change, adaptation includes a set of actions to moderate harm or exploit beneficial opportunities in response to climate change. To date, little research has addressed public policy options to frame the nation’s approach to adapt to a changing climate. In light of scientific evidence of extreme and unpredictable climate change, prudent policy requires consideration of what to do if markets and people fail to anticipate these changes, or are constrained in their ability to react. This issue brief is one in a series that results from the second phase of a domestic adaptation research project conducted by Resources for the Future. The briefs are primarily intended for use by decisionmakers in confronting the complex and difficult task of effectively adapting the United States to climate change impacts, but may also offer insight and value to scholars and the general public. This research was supported by a grant from the Smith‐Richardson Foundation.
Scientists expect climate change to affect the availability and quality of freshwater in distinctive ways from those previously experienced. As a result, many current methods to provide sustainable water supplies during extreme droughts, floods, and hurricanes may not be effective. New approaches are needed to respond to these complexly linked, cumulative effects associated with extreme climatic changes. The following actions can help create a policy environment that encourages adaptive responses in times of hydrologic uncertainty.
- To meet the increased demands for fresh water during periods of greater scarcity, regional adaptations will need to increase redundancy among natural and built systems to provide higher levels of functional resiliency. Planning will require frequent analyses of newly developed cooperative strategies to review both structural and non‐structural responses.
- Organizations that now focus mostly on short‐term responses to hurricanes, floods, and droughts will need to increase their effectiveness by linking regional and national levels of coordinated data collection and modeling to improve long‐term forecasts and proactive, adaptive responses.
- Additional coordination of federal and state agencies will enhance adaptive responses through long‐term strategic planning of shared solutions to water scarcity. These adaptations include new, properly located, deep storage reservoirs, optimal management of existing reservoirs, and shared information on the vulnerability of ecosystem services. Optimizing compatible land uses, floodplain protection, and urban design will increase groundwater recharge and storage during wet periods for use during dry periods.
- Newly developed and updated natural and built infrastructure will slow runoff and reduce erosion during floods with protected floodplains, expanded construction of green roofs, water gardens, retention ponds, and widely distributed storage reservoirs.
- Existing water‐storage and treatment infrastructure is aging and needs thorough evaluation and upgrading. Agencies will need to monitor reservoir storage capacities because larger and more frequent floods increase sediment transport and infilling.
- Decoupling storm‐flow runoff from systems connected to sewage treatment plants in urban and suburban basins will increase downstream water quality during floods and integrate centralized and decentralized natural infrastructure (e.g., wetlands and floodplains).
- Revision of the National Flood Insurance Program will need to consider the full, long‐term costs of floods, such as losses of ecosystem services in floodplains and coastal zones. Visualization of possible floods will enhance communication, resulting in more resilience insurance programs that include planning for protected river corridors and greenways.
- Future forecasts based on observations from improved satellites and atmospheric modeling will provide longer lead times for effectively alerting the public to risks of extreme droughts, floods, and hurricanes and will enhance adaptive responses. Improved forecasts will decrease losses and help to avoid rapidly increasing insurance premiums.
- Engaging grassroots programs and diverse stakeholders working on responses to climate change will increase opportunities for teachers, students, and the general public to become more aware of regional and temporal variability in precipitation.
- Learning from regional comparisons of adaptive responses to extreme variations in freshwater availability can provide exchanges of innovative policies. In addition, some adaptive responses will need to develop at the national level as more individuals, agencies, and organizations work together across traditional lines of communication to learn from past limitations. This framework can increase awareness and communication about options for responding to seasonal and inter‐annual variability of precipitation among participants across regions.