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Long Island Sound Estuaries and Embayments​

The USGS conducts monitoring and interdisciplinary studies to understand and quantify water quality, ecosystems, and processes in the estuaries and embayments of Long Island Sound.

Estuaries (tidal areas at the mouths of rivers) and embayments (recesses in the coastline) are nearshore areas where freshwater and saltwater mix. They often are partially protected from ocean waves by barrier islands or the configuration of the coastline. Estuaries and embayments provide important habitat for fish, migratory birds, and shellfish and support recreational activities such as boating and fishing. Water quality and habitat in these nearshore areas are highly vulnerable to stressors resulting from increasing development and climate change. 

USGS is conducting several studies in which in-depth analysis of observational data and numerical models is used to estimate the vulnerability of mainland infrastructure to coastal flooding and marsh erosion. Models are used to investigate changes in the propagation of extreme water levels from storms to estuarine and embayment coastlines following major events such as Hurricane Sandy. Models and observational data are used the investigate the role of wave characteristics, water depth and marsh elevation in the lateral erosion and disappearance of marshes in coastal embayments. Several observational and modeling studies are also being conducted to document water-quality conditions in near-shore areas and better understand contaminant delivery to Long Island Sound. Offshore monitoring is conducted to determine spatially and temporally variable concentrations of nutrients, pathogens, dissolved oxygen and other water-quality constituents in selected estuaries and embayments of Long Island Sound. Data from these networks are used by USGS and other stakeholders to address water-management issues and support other hydrologic studies.

Explore the Estuaries and Embayments page for more information on current and recently completed USGS studies, monitoring programs, and publications.