Do waterbody classifications predict water quality?
Many states classify waterbodies according to groups of designated uses, which suggests that classifications may be correlated with water quality. The primary assessments of water quality in the United States (the Biennial Integrated Water Quality Reports) do not consider classification, so the relationship between classification and water quality is untested. Additionally, water quality has been shown to be influenced by watershed land use; however, land use is not typically part of waterbody classification systems. To determine the relationships between waterbody classification, water quality, watershed land cover, and forest fragmentation, we analyzed existing water quality data for the State of Connecticut from the United States Geological Survey and the Connecticut Department of Energy and Environmental Protection and land cover data from the National Land Cover Dataset. Connecticut uses a unique classification system that includes separation of drinking water sources (Class AA) and waterbodies receiving waste water discharges (Class B). Using a comparison of multiple means, we found that Class B waters had higher levels of nitrogen, solids, chloride, sodium, dissolved copper, total iron, and dissolved manganese than Class AA waters. Watersheds upstream of Class B segments had less forest cover, more development and more impervious cover than watersheds upstream of Class AA segments. Class A sites had some similarities in water quality and land cover with Class AA sites and some with Class B sites. The subset of Class B waterbodies with "Class AA-like" water quality also had "Class AA-like" land cover. Based on this and a multiple linear regression analysis, we found that water quality is more closely related to watershed land cover and forest fragmentation than to waterbody classification. Our results suggest that watershed land cover likely is a better proxy for water quality than waterbody classification.
Department of Natural Resources and the Environment, University of Connecticut, 1376 Storrs Road, Unit 4087, Storrs, CT 06269-4087, USA. Electronic address: janet.barclay@uconn.edu.
Janet R
JR
Barclay
Department of Natural Resources and the Environment, University of Connecticut, 1376 Storrs Road, Unit 4087, Storrs, CT 06269-4087, USA.
Hannah
H
Tripp
Department of Energy and Environmental Protection, State of Connecticut, 79 Elm Street, Hartford, CT 06106-5127, USA.
Christopher J
CJ
Bellucci
Department of Natural Resources and the Environment, University of Connecticut, 1376 Storrs Road, Unit 4087, Storrs, CT 06269-4087, USA.
Glenn
G
Warner
Department of Natural Resources and the Environment, University of Connecticut, 1376 Storrs Road, Unit 4087, Storrs, CT 06269-4087, USA; Center for Environmental Science and Engineering, University of Connecticut, 3107 Horsebarn Hill Rd., Unit 4210, Storrs, CT 06269-4210, USA.
Ashley M
AM
Helton
D002712:Chlorides / Q000032:analysis; D003300:Copper / Q000032:analysis; D004784:Environmental Monitoring; D065928:Forests; D005618:Fresh Water / Q000032:analysis*; D007501:Iron / Q000032:analysis; D008345:Manganese / Q000032:analysis; D009584:Nitrogen / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000032:analysis; D060753:Water Quality; D014881:Water Supply
D002712:Chlorides; D014874:Water Pollutants, Chemical; D008345:Manganese; D003300:Copper; D007501:Iron; D009584:Nitrogen
Designated use; Forest fragmentation; Land cover; Water policy; Water quality; Waterbody classification