Crystalline Rock Aquifer

Water levels in six wells were measured in crystalline-rock aquifers in the Piedmont and Blue Ridge Physiographic Provinces of Georgia. In this area, water is present in discontinuous joints and fractures and may be confined or unconfined. In general, crystalline-rock aquifers are local in extent and can be greatly affected by localized water use and climate. During 2010, about 64 million gallons per day (Mgal/d) were withdrawn from the crystalline-rock aquifers in Georgia, primarily for public-supply withdrawals (Lawrence, 2016). Hydrographs for selected wells (below) illustrate monthly mean water levels for the period of record. The hydrographs show periodic upward or downward trends that reflect changes in precipitation and pumping.

Period of Record (POR) and Ten Year Trends
Station Name County POR First
POR Trend
Ten Year
Trend (ft/yr)
12JJ04 Dawson xx xx yy
11FF04 DeKalb xx xx yy
10DD02 Fulton xx xx yy
20GG41 Madison xx xx yy
21BB04 Madison xx xx yy
16MM03 White xx xx yy

Well Locations with Ten Year Trend Icons

up arrow icon down arrow icon    Arrow icons represent upward or downward water level trend. Calculations based on last 10 years of data.
dot icon    Dot icon represents trend slope less than 0.01 ft/yr. or less than 100 data points from the last 10yrs. of data.
up arrow icon with graph down arrow icon with graph dot icon with graph    Split color icons represent wells with graphs.
(Click or hover over map icons for more information.)

Monthly Mean Data Graphs

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Station name: 12JJ04
County: Dawson
Number: 342125084083301

Slope (ft/yr):

Station name: 10DD02
County: Fulton
Number: 334207084254801

Slope (ft/yr):

Station name: 11FF04
County: Dekalb
Number: 335517084164001

Slope (ft/yr):

Station name: 16MM03
County: White
Number: 344314083433201

Slope (ft/yr):


  • Lawrence, S.J., 2016, Water use in Georgia by county for 2010 and water-use trends, 1985–2010 (ver. 1.1, January 2016): U.S. Geological Survey Open-File Report 2015–1230, 206 p., accessed August 24, 2016, at