Reconnaissance of baseflow water quality in Georgia
Alhadeff, S. J.
Landers, Mark N.
MetadataShow full item record
During 1995, the Georgia Department of Natural Resources, Georgia Environmental Protection Division (GaEPD) adopted and implemented significant changes to the strategy for water-quality trend monitoring in Georgia. The changes were made to implement a rotat-ing basin monitoring approach in support of the River Ba-sin Management Planning (RBMP) program. Important environmental water-quality indicator parameters that support RBMP objectives are total suspended solids, tur-bidity, fecal coliform, total nitrogen, total phosphorus, and pH. Through many U. S. Geological Survey water-quality projects, including cooperative projects with GaEPD, a large database of water-quality analyses exists; samples have been collected since the late 1960s, with many analy-ses representing baseflow conditions. However, the spa-tial variability of baseflow water quality in Georgia has received little documentation. A statewide reconnaissance-level study of baseflow water quality provides information that may be valuable in assessing background water qual-ity, minimally affected by anthropogenic pollutant sources. Regionalized unit-area streamflow percentiles provide a basis for selecting water-quality sample discharges that likely represent baseflow. Samples taken during baseflow must be screened to remove those with apparent point-source influences. The reconnaissance-level approach has several assumptions that are probably violated to some extent. However, the resulting maps of screened, base-flow water-quality characteristics provide a reconnais-sance-level indicator of background concentrations of con-stituents during baseflow.