MANAGING GROUNDWATER DURING DROUGHTS WITH DFCS AND MAG: CONFINED VERSUS UNCONFINED?

Droughts result in water scarcity. Primarily, this lack of water resources impacts surface-water users because they are directly dependent upon rainfall and runoff. However, water systems supplied by shallow water-table aquifers often experience problems as well. Deeper, confined aquifers generally contain plenty of water and remain reliable sources of water unless they have been severely over-pumped prior to the drought. However, confined aquifers are susceptible to permanent loss of storage from lack of management during droughts. Examples of actual drought management practices provide insight into the need for better groundwater data, better groundwater education and alternate management strategies. The most commonly applied solutions observed in case studies included increased pumping, drilling new wells and recompletions. All of these responses solve short-term water needs but increase long-term management problems and seldom result in new management plans for the next drought. Drought preparedness and contingency plans are more commonly part of surface water management but groundwater dependent supply systems tend to be less proactive. Observations from recent droughts reveal serious flaws in management strategies to sustain groundwater resources. The best groundwater management practices occurred where groundwater and surface water were obviously connected and DFCs could be observed easily and monitored frequently. The least effective management occurred in deep, confined aquifers where monitoring and assessment often occurred annually. Almost all drought responses indicated gaps in hydrogeologic understanding by decision makers and participating stakeholders. Several suggestions to improve drought management and sustainability in shallow, unconfined and deep, confined aquifers are included.