Nutrient Loading

The U.S. Geological Survey, New England Water Science Center, in collaboration with the U.S. Environmental Protection Agency (EPA), is modeling seasonal nutrient loads to Long Island Sound (LIS). Nutrients that originate from within the 41,867-square-mile section of the LIS watershed that is north of the Sound include both point (specific) and nonpoint (widespread) sources. Dynamic modeling of the...

Coastal estuaries in southern New England and New York show the effects of excess nutrients and coastal eutrophication. These include excessive growth of macroalgae, excessive blooms of phytoplankton, oxygen depletion, hypoxia and deteriorated substrates. State and Federal regulators have responded to these nutrient-caused impairments by requiring more stringent permit limits for National...

In 2019 the USGS began a partnership with the U.S. Environmental Protection Agency (EPA) Office of Research and Development (ORD), EPA Region 1 Southeast New England Program for Coastal Watershed Restoration (SNEP), Barnstable Clean Water Coalition (BCWC), and other stakeholders to conduct hydrologic monitoring and assessment in support of multifaceted nutrient-management activities in the Three...

The U.S. Geological Survey (USGS) New England Water Science Center installed, operated, and maintained surface water-quality sites at the Chequessett Neck Road dike on the Herring River from November 2015 through September 2018.

The Pawcatuck River and the Pawcatuck River Estuary and Little Narragansett Bay form part of the boundary between the States of Connecticut and Rhode Island. Both states have identified water quality impairments within these waters related to nutrients (insufficient oxygen) and bacteria. Studies of the eutrophication potential of Long Island Sound embayments have identified that the Pawcatuck...

In 2019 USGS completed a study designed to develop and evaluate a phased site-assessment approach for determining the hydrologic suitability of sites being considered for permeable reactive barrier installation on Cape Cod. The approach provides a template for town officials and other stakeholders to follow when considering PRBs for passive treatment of nitrogen in groundwater on Cape Cod and...

The U.S. Geological Survey and the U.S. Environmental Protection Agency are collaborating on a study to better understand changes to groundwater quality beneath a densely developed coastal neighborhood as it undergoes conversion from onsite wastewater disposal to municipal sewering.

Urban stormwater runoff contains high phosphorus concentrations that contribute to the eutrophication to receiving waters. Recent studies have further shown that leaf fall management presents an opportunity to maximize the effectiveness of common municipal practices such as street cleaning and leaf litter removal and substantially nutrient loading.

Since 1979, the USGS has monitored water quality in the major river basins of Rhode Island contributing to Narragansett Bay.

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.

River-borne nutrients, especially nitrogen, contribute to water-quality degradation in Long Island Sound. The Connecticut River is the largest tributary to the Sound, and quantification of nutrient loads from the three upper States in the watershed, as well as the State of Connecticut, is essential for prioritizing efforts to improve the Sound’s water quality.

Note: SELDM is now on version 1.1.1.