11 Environmental Geoscience & Hydrogeology (Posters)
Thursday, 12 March 2009
1:30 PM - 5:30 PM
STORM-SURGE INDUCED WATER-QUALITY CHANGES IN AN UNCONFINED COASTAL AQUIFER SYSTEM
Paper number: 11-13
Program: Technical Sessions
Time: 1:30 PM – 5:30 PM
Authors
Abstract
Numerous coastal communities rely heavily on groundwater for irrigation and potable water supply. The unconfined nature of most shallow coastal aquifers leaves them inherently vulnerable to water-quality degradation associated with infiltrating saltwater from tropical cyclone storm surges. While hydrogeological models can be used to predict water-quality changes due to such phenomena, these mathematical solutions are rarely verified by long-term, “before and after” monitoring data. One such data set exists for a site located on the U.S. Gulf Coast in an area that was inundated by a significant storm surge during Hurricane Katrina in August 2005. Water-quality data, collected quarterly from 1990 to the present in several wells that are screened in an unconfined surficial aquifer system, show baseline (pre-surge) groundwater conditions at the site, the initial impact immediately after the flooding event, and the eventual recovery of several key water-quality parameters to pre-surge levels.