Water quality and contaminants in stream surface waters collected in the Delmarva Peninsula, 2022 (ver. 1.1, June 2026)

This data release contains the concentration and quality assurance results for 29 streams, sampled twice, and 1 stream, sampled once, in the Chesapeake Bay Delmarva row crop region (Maryland and Delaware, USA) for the following constituent classes (count of constituents); field and water-quality parameters (9), nutrients/anions (13), dissolved organic carbon (1), per- and polyfluoroalkyl substances (PFAS) (34), aqueous hazards (52), net estrogenicity (1), and major cations and trace elements (55). Samples were collected between May and July 2022. PFAS, nutrient, and water-quality class constituents were analyzed at the U.S. Geological Survey (USGS) National Water Quality Laboratory (NWQL) Denver, Colorado. Anions, dissolved organic carbon, major cations, and trace elements were analyzed at the USGS Analytical Trace Element Chemistry-Common Services Laboratory (ATEC-CSL) in Boulder, Colorado. Aqueous hazards were analyzed at the USGS Integrated Water Chemistry Laboratory (IWCL) in Boulder, Colorado. Estrogenicity was analyzed at the USGS Eastern Ecological Science Center (EESC, previously Leetown Science Center) in Kearneysville, West Virginia. The respective methods associated with the analyses for constituents are listed in Table_2_Methods. Versioning of this data release was required to adhere to privacy agreements. Please see versioning_statement.txt for more information.

First release: 2024
Revised: June 2026 (ver. 1.1)