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Ecosystem Delineation and Assessment

MassBays is a large and complex system. A detailed characterization of the nearshore estuarine system highlights primary resources that need to be protected and issues to be addressed to improve habitat conditions.

MassBays works primarily in the near-shore, estuarine systems of the region, in light of the strong leadership of Massachusetts’ watershed associations, and the significant and effective investment the Commonwealth has made in ocean planning. To support this work and as an alternative to a coastal delineation that uses municipal boundaries, MassBays uses ecosystem-based landward and seaward boundaries to define the MassBays planning area. Using these boundaries and geospatially available data, a glimpse into the relative ecological condition of estuaries within the Ipswich, Massachusetts, and Cape Cod Bays was assessed. 

Taking a closer look at the Bays

The diversity across MassBays' planning area is captured in the Estuary Delineation and Assessment Report (EDA) and associated Story Map. With the EDA, we can look more closely at 65 assessment areas in our geographic area of interest -- the coastal zone of Ipswich Bay, Massachusetts Bay and Cape Cod Bay. Broadly, the assessment areas include estuarine embayments, rocky shorelines, and sandy beaches and dunes. Characterization is based on attributes that include tidal flats, shorebird habitat and nesting sites, anadromous fish runs, salt marsh, eelgrass beds, shellfish habitat, impervious area, stormwater and wastewater discharge, land use change, population density, water quality conditions, fish barriers, designated shellfish growing area classification, and stream crossings.


Specific datasets are used to categorize embayments by type and to establish target conditions. EDA 2.0 is a tool to track changes in conditions over time and inform our State of the Bays reporting.

In addition to the interactive Story Map, you will find the full 2017 report prepared by GeoSyntec Consultants linked below. Data layers in the Story Map will be updated as they become available. The next update of the EDA (EDA 3.0) will be done during 2023.

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