GROUNDWATER EXPLORATION AND DEVELOPMENT IN IGNEOUS AND METAMORPHIC ROCKS: PART II – CASE HISTORIES FROM THE SOUTHEASTERN PIEDMONT/BLUE RIDGE PROVINCE

The growing demand for water has pushed many local and municipal water systems to, or beyond, their limits. Many of north Georgia’s counties and cities rely almost completely on surface water. With the continuing conflict between Georgia, Alabama, and Florida concerning river water allocations, surface water withdrawals will be managed and monitored more closely as demand increases. There is an immediate need for alternative sources of water to be located, evaluated, and put into the distribution systems. For north Georgia and other Piedmont/Blue Ridge areas to continue to rely so heavily on surface water is not acceptable.

There is a pervasive misconception that there is little groundwater in igneous and metamorphic rocks in the Piedmont/Blue Ridge province. Because of this, groundwater typically has been ignored or deemed unreliable. Compounding this misconception, many techniques used for locating groundwater in these kinds of rock are very unreliable. Non-scientific as well as misguided scientific methods for selecting drilling sites have further hindered using groundwater as an alternative water source. Recent advances in scientific approaches for evaluating groundwater potential in igneous and metamorphic rocks have taken much of the risk out of locating viable and sustainable sources of groundwater. When a proper scientific approach is taken, the probability of locating successful water wells is greatly increased. City, County, and other water systems managers need to be informed about scientific approaches that are applicable to their specific needs and geologic constraints.

Three case histories from the southeastern U.S. are presented where City, County, and other water systems have conducted expensive groundwater exploration programs only to drill dry holes or low-yielding wells, even where the exploration programs used “high-tech” approaches that were presented as being the best tools for finding groundwater. The fatal flaw in many of these exploration programs is the lack of knowledge of site-specific geology. Alternatively, the exploration and development approach outlined by Crawford and Kath (Part I, this conference) has been very successful in exploration and development of groundwater resources in igneous and metamorphic rocks.