Groundwater under stress: the importance of management

The most significant water problem facing the United States and the world is the scarcity of water. Scarcity is expected to intensify during the twenty-first century due to global population growth, economic growth and the need to protect environmental assets. In many regions, climate change may cause scarcity to become more acute. Groundwater has the capacity to buffer extreme hydrologic events because recharge is not directly tied to precipitation and run-off events. Groundwater storage offers many opportunities to increase storage and enhance the general water supply. The value of groundwater will increase as scarcity intensifies and effective groundwater management will be required if groundwater values are to be reaped. Effective groundwater management will require attention to certain well-established economic principles. Persistent overdraft is always self terminating. Individualistically competitive modes of extraction are inefficient. It is virtually always cheaper to prevent pollution in the first place than to remediate it. Groundwater management schemes appear to be most effective when they are locally developed and managed. Such schemes can regulate extractions and/or recharge either directly or indirectly. Evidence from the United States suggests that direct regulations can be made to work if they focus on recharge and developing supplementary sources of water. Evidence from South Asia suggests that regulation of extractions and provision of recharge water is most effective when indirect measures are used in which groundwater and ancillary variables such as electricity are co-managed. This evidence suggests that as supplementary sources of supply become scarce, innovative and indirect groundwater management schemes are likely to become more common.