Climate Change Adaptation

Meeting Water Demand in a Climate of Uncertainty

Meeting increasing demands for water is a constant challenge at all levels of government, but pressure to find both short-term and long-term water supply solutions has never been as urgent in many regions of the country as it is today. States, tribes, municipalities, industry, and water supply entities are engaged in water resource planning to meet current and future challenges posed by climate change, increasing pressures on existing resources from population growth, competition for resources among various industries, and quantity and quality issues associated with current supplies.

Climate change is the glaring wild card in our water resource planning deck. While we may have long-term global climate models, we simply don’t have the ability to predict how and where droughts, floods, sea-level changes, and erratic weather events, such as hurricanes and tornadoes, will impact groundwater and surface water resources at a local scale.

Water conservation is usually the first step taken to help stretch existing resources; however, the hunt is on to identify new water sources to meet increasing demands. Alternative water resources can be an important part of this strategy. Untapped or underutilized groundwater sources may be available locally to supplement or provide needed capacity to water systems. Brackish groundwater desalination, stormwater harvesting, aquifer storage and recovery, and water reuse are four groundwater-related resources that are either currently used or being considered for development in many areas of the nation.

Federal, state, and tribal governments will need to encourage and facilitate the use of these unconventional water sources. A challenge to using such resources is local level acceptance that these are viable, long-term resources that justify the expense associated with investigation and characterization, as well as development of the infrastructure needed to utilize them.

Why Alternative Water Supplies Matter to Groundwater

Water resource planners are facing unprecedented challenges in efforts to maintain current and find new resources to meet demands. Groundwater is being tapped more and more for a host of different uses—public and private water supplies, agricultural irrigation, industrial, aquaculture, livestock, mining, thermoelectric power, carbon sequestration, and environmental in-stream flows—all vying for what is essentially a static or decreasing resource. Changes in historic rainfall and temperature patterns as well as pressures from increased population growth are adding urgency to the need to find additional water resources. Predicted climate change and population growth trends are driving the need to identify alternative water resources.