Fluctuations in Groundwater Levels Related to Regional and Local Withdrawals in the Fractured-Bedrock Groundwater System in Northern Wake County, North Carolina

A study of dewatering of the fractured-bedrock aquifer in a localized area of east-central North Carolina was conducted from March 2008 through February 2009 to gain an understanding of why some privately owned wells and monitoring wells were intermittently dry.  Although the study itself was localized in nature, the resulting water-resources data and information produced from the study will help enable resource managers to make sound water-supply and water-use decisions in similar crystalline-rock aquifer setting in parts of the Piedmont and Blue Ridge Physiographic Provinces. 

In June 2005, homeowners in a subdivision of approximately 11 homes on lots approximately 1 to 2 acres in size in an unincorporated area of Wake County, North Carolina, reported extremely low water pressure and temporarily dry wells during a brief period. This area of the State, which is in the Piedmont Physiographic Province, is undergoing rapid growth and development. Similar well conditions were reported again in July 2007.  In an effort to evaluate aquifer conditions in the area of intermittent water loss, a study was begun in March 2008 to measure and monitor water levels and groundwater use.

During the study period from March 2008 through February 2009, regular dewatering of the fractured-bedrock aquifer was documented with water levels in many wells ranging between 100 and 200 feet below land surface.   Prior to this period, water levels from the 1980s through the late 1990s were reported to range from 15 to 50 feet below land surface.  The study area includes three community wells and more than 30 private wells within a 2,000-foot radius of the dewatered private wells.