More frequent and longer droughts coupled with increased hurricanes and floods could lead to a future of greater vulnerability for freshwater resources in the United States. Most current freshwater management policies were designed in the last 60 to 80 years, a period climatologists now recognize as unusually wet. But precipitation patterns in the coming decades are expected to return to “normal” and many regions may be much drier. And regardless of climate speculation, policymakers are already facing many serious issues in dealing with the current shortage of high-quality water and ensuring sufficient water quantity to meet the growing demands.
The Problem
Droughts throughout the country are leading to declines in lake and stream levels and rivers are drying out more often. Rainfall and snowfall are more unevenly distributed from year to year in many areas and a warmer climate will likely mean greater future variation in precipitation and evaporation. Climatic extremes in the next 50 years could be fundamentally different from the past so responding to their outcomes will mean studying patterns, reassessing current systems, and adapting to new circumstances.
Although several U.S. regions are familiar with drought—some policies and adaptive responses have been effective in coping with limited water quantity, quality and drought-related wildfires in the arid West and parts of the Midwest—losses are increasing both in scope and frequency. New approaches are needed. Two recent multi-year droughts in the southeastern U.S. have stimulated some changes in policy and resulted in a wider recognition of the need for more long-term planning to ensure the value of natural flows and protect biotic processes that sustain freshwater ecosystem services.
Recent droughts throughout eastern states have also served as a reminder that aging infrastructure associated with storage, treatment, and delivery of water in urban centers and rural areas is in need of updating. Large amounts of leakage in some delivery systems results from century-old pipes and the combined storm drainage and sewage treatment facilities are too often over-burdened during intense storms.
Population distributions are becoming more concentrated in urban centers across the country and people now rely on a combination of surface water and groundwater. Aquifers will become increasingly unreliable during prolonged droughts after decades of over pumping and limited aquifer recharge. Pumping, below ground storage in deep aquifers (during wet periods), and recovery of water during droughts is one approach. However, this “solution” can lead to the contamination of naturally pure groundwater and create new problems.
Policy Response
States and non-governmental organizations have developed some new ways to adapt but sharing these ideas have yet to be adapted for wider use. There are numerous “climate centers” at state, regional, and national levels but their activities need to be integrated so the general public can learn how to better organize responses to increasingly severe drought conditions. Preparations for hurricanes and flooding have increased after Katrina, but similar coordinated national and regional efforts to address droughts are needed.
In the past, the main economic losses were agricultural as supplies for irrigating crops were often limited. More drought-ravaged areas will likely see adverse economic impacts in the future. Long-term “insurance” will most likely come from better management of natural infrastructure like wetlands, floodplains and well-managed forested source areas. Some cities and counties as well as state and federal agencies are creating incentives to pay landowners to improve their management practices. These investments will pay off in the years ahead as the value of natural ecosystem services is increasingly recognized by the general public and policy makers.
Read Covich's in-depth exploration of climate change adaptation and U.S. freshwater systems is entitled, "Emerging Climate Change Impacts on Freshwater Resources: A Perspective on Transformed Watersheds," an installment from a six-part series of U.S. climate change adaptation policy reports.
