Surface Water Quality Monitoring in Connecticut

Science Center Objects

The 2,983 miles of streams in Connecticut support a range of uses, including drinking water, recreation, and fish and shellfish habitat.  The State is required by the Clean Water Act to assess the health of these waters every two years.

To assist the State in meeting this requirement, and support long-term assessment of water quality trends, the USGS operates a surface water quality monitoring network in the State.  Stream basins are sampled on a rotating basis, in cooperation with the Connecticut Department of Energy and Environmental Protection. In Fiscal Year 2018, sampling is being conducted at stations on the Thames, Connecticut, Quinipiac, Housatonic, and Southwest Coastal watersheds. USGS procedures for quality assurance and quality control are followed, and the QA/QC results are reported. The following analytes are will be sampled, analyzed, and reported:

  • Field parameters (water temperature, specific conductance, dissolved oxygen, pH, turbidity, and alkalinity)
  • Total and dissolved nutrients (11 analytes)
  • Total organic carbon
  • Indicator bacteria (E-coli)
  • Major ions  (9 analytes)
  • Dissolved trace metals (15 analytes)