Inventorying Ground Water in Crystalline Rocks of Piedmont Region

Abstract

A methodology is described for estimating a “Ground Water Working Inventory” for areas of the eastern Piedmont Province drawing ground water from crystalline rocks. The approach can improve efficiency in water resource and land‐use planning and use of surface and ground water resources. Calculation of the 7‐day, 10‐year and 7‐day, 1‐year flows from stream gage data together with application of geologic data and information calculated from 24‐hr pumping tests allow the outlining of areas more favorable and less favorable for ground water development. The Ground Water Working Inventory based on the 7‐day low‐flow calculations allows estimates of available water to be made and permits land‐use planners to make rational decisions about residential densities and other water‐related issues. Political bodies and planners can use the methodology to guide development according to how large a role ground water is to play in local water supply planning and management. High density development can be discouraged in those areas where ground water is limited and encouraged where commitments for surface water supplies have been made. Additionally, the inventory provides information which strengthens planning for use of ground water as a supplement to surface water supplies.