September 2025

The MassDEP Wetlands datalayer comprises two feature types, polygons and arcs (lines). The attribute codes in the polygon layer describe different types of wetland environments and the arc attributes describe line types based on adjacent polygon types or arcs defined as hydrologic connections.In this service the wetland areas are displayed using outlines and labeled with wetland code abbreviation. This symbology is useful for displaying the data atop aerial imagery.Please see https://www.mass.gov/info-details/massgis-data-massdep-wetlands-2005 for more details.

December 2017

This data set represents the extent, approximate location and type of wetlands and deepwater habitats in Massachusetts. These data delineate the areal extent of wetlands and surface waters as defined by Cowardin et al. (1979).The National Wetlands Inventory - Version 2, Surface Waters and Wetlands Inventory was derived by retaining the wetland and deepwater polygons that compose the NWI digital wetlands spatial data layer and reintroducing any linear wetland or surface water features that were orphaned from the original NWI hard copy maps by converting them to narrow polygonal features. Additionally, the data are supplemented with hydrography data, buffered to become polygonal features, as a secondary source for any single-line stream features not mapped by the NWI and to complete segmented connections. Wetlands for most projects mapped after 2015 were mapped to include all surface water features and are not derived data. The linear hydrography dataset used to derive Version 2 was the U.S. Geological Survey's National Hydrography Dataset (NHD). Specific information on the NHD version used to derive Version 2 and where Version 2 was mapped can be found in the 'comments' field of the Wetlands_Project_Metadata feature class. Certain wetland habitats are excluded from the National mapping program because of the limitations of aerial imagery as the primary data source used to detect wetlands. These habitats include seagrasses or submerged aquatic vegetation that are found in the intertidal and subtidal zones of estuaries and near shore coastal waters. Some deepwater reef communities (coral or tuberficid worm reefs) have also been excluded from the inventory. These habitats, because of their depth, go undetected by aerial imagery. By policy, the Service also excludes certain types of "farmed wetlands" as may be defined by the Food Security Act or that do not coincide with the Cowardin et al. definition. Contact the Service's Regional Wetland Coordinator for additional information on what types of farmed wetlands are included on wetland maps. This dataset should be used in conjunction with the Wetlands_Project_Metadata layer, which contains project specific wetlands mapping procedures and information on dates, scales and emulsion of imagery used to map the wetlands within specific project boundaries.MassGIS downloaded the data from https://www.fws.gov/wetlands/Data/State-Downloads.html on November 12, 2020 and projected it to the Mass. State Plane Meters NAD 1983 Mainland coordinate system.

Hydrography polygon features in Easton, Massachusetts. Compiled from 2017 vector mapping project conducted by WSP. The aerial photographic mission was carried out on April 12, 2017. The vector data was collected at scale of 1"= 40'.

Bitly Link for this page: https://bit.ly/mvcfloodcompareAll datasets presented here are compiled by organizations other than the Martha's Vineyard Commission (MVC). The MVC has simply pulled these datasets into one map viewer for ease of direct visual comparison. The MVC encourages the viewer of this map to do their due diligence and research to understand the wide array of methodologies used to model flood inundation and sea level rise.The 3 Flood Inundation datasets presented are: FEMA (100 year or 1% annual probability flood zone) as per Effective Year 2016 data release.Mass Coast - Coastal Flood Risk Model (presented as flood probability for 3 future time horizons)Storm Tide Pathways - Flood Inundation Extents based on Total Water Level (in feet) relative to MLLW. There's a separate data layer for each inundation plane in half foot increments from 2.5ft MLLW to 19.5ft MLLW.SLOSH - Hurricane Inundation - Worst Case ScenarioVarious Links to learn more about these datasets:FEMA 2016 Data for Dukes CountyCoastal Zone Management Viewer: Mass Coast - Coastal Flood Risk Model Mass Coast 2030 Flood RiskMass Coast 2050 Flood RiskMass Coast 2070 Flood RiskMass Coast FAQStorm Tide Pathways App and Storm Tide Pathways InfoSLOSH - produced by NOAA & NWS v3 June 2022 (high tide scenario)The legend for the Mass Coast (MC-FRM) data shows the:The Probabilities 0.1% (in coral color) to 100% (in dark blue) is the Probability of Inundation - which is the chance of becoming flooded at some point each year.Coast Flood Exceedance Probabilities shown in the legend display the modeled outputs ranging from 0.1% (0.001, otherwise known as the 1,000-year storm) to 100% (1.0), which corresponds to the one-year storm. -- The 100% probability level generally corresponds to the annual high water value (NOT the average high tide).

Other data on this map include Salt Marshes, Wetlands MassDEP, Wetland Migration SLAMM Model (year 2070 with high sea level rise), Parcel Lines, and Building Roofprints.

The wetlands data (linear and area features) presented in the map for Dukes County were obtained from MassGIS and published by MassDEP (pub. 2017 - still most current available as of Feb. 2025). See MassGIS website for methodology details. The parcel data are those hosted by MassGIS and have been filtered to only show those parcels within Dukes County.Please refer to the respective websites to understand the level of accuracy and use constraints associated with these datasets.The stream, intermittent stream, and wetland area buffers (100ft and 200ft) were processed by the Martha's Vineyard Commission in Jan. 2025 from the MassDEP wetlands data.This web map was compiled by the Martha's Vineyard Commission for planning purposes only. The parcel data will appear once zoomed-in on the map.

This map shows the location of wetland areas inside of the Ipswich Study Area This map can be used to show where wetlands are located within the Ipswich Study Area.

This dataset consists of a set of annual land cover products for 1985-2017 produced using the CCDC algorithm as part of Mass Audubon's Losing Ground 6 analysis.

The sixth edition of Mass Audubon’s Losing Ground series of reports builds on the methods first employed in Losing Ground 5. Following LG5 analysis, the Continuous Change Detection and Classification (CCDC) algorithm, a harmonic modeling approach, was used to identify land cover changes and characterizes the spectral-temporal properties of stable land cover “segments” based on dense time series of all high-quality Landsat observations (Zhu et al. 2012; Zhu and Woodcock 2014). However, the LG6 analysis improves on the training data and land cover labeling system used in LG5. For LG6, we developed a modified version of the MassGIS 2005 Land Use/Land Cover polygons and legend in an effort to provide greater thematic detail as well as increase the ecological relevancy of the mapped results. Integrating the CCDC approach and our detailed land cover training dataset, we produced a 30-year time series of land cover maps for the Massachusetts Mainland and Islands as well as offshore waters. The original maps generated by the CCDC algorithms were then manually post-processed to improve spatial accuracy of change detection results, and final results including post-processing steps are available here.

The Losing Ground 6 Classification includes the following land cover classes adapted from the 2005 MassGIS Land Use and 1m Impervious surface datasets:

> Man-made Built -- Greater than 25% constructed surfaces such as buildings, roads, parking lots, brick, asphalt, concrete

> Man-made Bare -- Areas of man-made compacted soil or material such as mining or unpaved parking lots

> Natural Barren -- Natural occurring barren areas (i.e. rocky shores, sand, bare soil)

> Forest -- Pixels dominated by closed-canopy forest in leaf-on imagery, as well as mixed-cover pixels spanning forest edges that do not meet criteria for Built.

> Forested Wetland -- Persistently vegetated wetlands dominated by tree cover; often found adjacent to rivers and in low-lying areas; Reference MassDEP Wetlands

> Plantation -- Planted tree crops, includes orchards and tree farms

> Cultural grassland -- Dominated by herbaceous cover, includes pastures, fields, and row crops

> Irrigated herbaceous -- Heavily managed grass cover, includes golf courses and (non-synthetic) athletic fields

> Successional/transitional forest -- Forest recovering after stand-replacing disturbance; Predominantly (> 25%) shrub cover, and some immature trees not large or dense enough to be classified as forest. It also includes areas that are more permanently shrubby, such as heath areas, wild blueberries or mountain laurel.

> Managed shrubland -- Woody vegetation maintained in a mid-successional state, e.g. powerline corridors; includes "self-managed" stable shrublands, e.g. coastal shrub/heathland (e.g. scrub oak)

> Open water -- Dominated by open-water conditions, little to no seasonal vegetation cover

> Non-forested wetland -- Persistently or seasonally vegetated wetlands with little to no tree cover; Includes freshwater emergent and shrub swamp wetland types; Reference MassDEP Wetlands

> Saltwater wetland -- Coastal wetlands, often herbaceous-dominated marsh and may show signs of ditching; Reference MassDEP Wetlands

> Active cranberry bog -- active and recently active cranberry bogs; notable red color and geometric patch shapes

A more complete description of training sources, class labels and codes, and definitions is available here.

Please contact Dr. Valerie Pasquarella (valpasq@bu.edu) with any questions regarding these data and potential use cases.

MassDEP wetlands (published 2017) based on year 2005 Color Infrared Photos (1:5,000) and year 1993 CIR photos (1:12,000). The former have not been field verified.

These data are for planning purposes only.Per the MassGIS website:"The wetlands boundaries shown on this map have been determined by photographic interpretation. They do not represent, and should not be used as, wetlands delineations under the Massachusetts Wetlands Protection Act (M.G.L. c. 131 §40) and its regulations. Wetlands boundary determination for other purposes, such as the Wetlands Protection Act MA Act M.G.L. c. 131 or local bylaws must use the relevant procedures and criteria."The attribute table contains a simplified wetland code adapted from 1:25,000 hydrography and a detailed (28 category) wetland code based on the Wetland Conservancy Program.See the MassGIS website for full metadata details.

100 ft upland buffer from MassDEP identified wetlands.

This MassDEP Hydrography layer is an enhanced version of the older U.S. Geological survey 1:25,000 Hydrography datalayer. It represents hydrographic (water-related) features, including surface water (lakes, ponds, and reservoirs), wetlands, bogs, flats, rivers, streams, and others.The layer is a hybrid of data based on USGS Digital Line Graphs (DLGs), scanned mylar separates obtained from the USGS, digitized hydrographic features from paper USGS 1:25,000 Topographic Quadrangle maps and data extracted from the MassDEP Wetlands datalayer. Areas within many surface water supply watersheds have been enhanced by using higher resolution streams and lakes from the MassDEP Wetlands datalayer, many areas have also been field verified.See full metadataMap service is also available.

Web application for viewing wetland resource areas including Wellesley's Wetlands Buffer Zone and Riverfront Area, as well as FEMA's Special Flood Hazard Areas.

description: James W. Sewall Company used its standard photointerpretation and ortho-mapping workflow and was assisted by NatureServe in crosswalking to NVC vegetation and wetlands mapping on approximately 115,926 acres across New England. Refuges include: Nulhegan NWR (VT), Pondicherry NWR (NH), Eastern Mass NWR (MA), Parker River NWR (MA), Rachel Carson NWR (ME), Sunkhaze Meadows NWR (ME), Moosehorn NWR (ME), Aroostook NWR (ME) and several island refuges in Massachusetts. Aerial photography using color infrared (CIR) film was acquired during the spring and early summer at a scale of 1"=1000' (1:12,000). Sewall's photointerpreter conducted fieldwork in conjunction with NatureServe and FWS staff to identify signature and establish what would be classified. Fieldwork was limited due to budgetary constraints, but all but the island refuges were visited - four by Sewall with NatureServe and/or USFW staff accompanying, and the remainder by NatureServe and USFW staff only, who provided detailed feedback to Sewall in the form of annotated maps and GIS data. For the island refuges, NatureServe and USFW staff provided data and suggested NVC classes. This shapefile contains the interpeted attributes and has been "crosswalked" with NVC codes (up to 3 per polygon).; abstract: James W. Sewall Company used its standard photointerpretation and ortho-mapping workflow and was assisted by NatureServe in crosswalking to NVC vegetation and wetlands mapping on approximately 115,926 acres across New England. Refuges include: Nulhegan NWR (VT), Pondicherry NWR (NH), Eastern Mass NWR (MA), Parker River NWR (MA), Rachel Carson NWR (ME), Sunkhaze Meadows NWR (ME), Moosehorn NWR (ME), Aroostook NWR (ME) and several island refuges in Massachusetts. Aerial photography using color infrared (CIR) film was acquired during the spring and early summer at a scale of 1"=1000' (1:12,000). Sewall's photointerpreter conducted fieldwork in conjunction with NatureServe and FWS staff to identify signature and establish what would be classified. Fieldwork was limited due to budgetary constraints, but all but the island refuges were visited - four by Sewall with NatureServe and/or USFW staff accompanying, and the remainder by NatureServe and USFW staff only, who provided detailed feedback to Sewall in the form of annotated maps and GIS data. For the island refuges, NatureServe and USFW staff provided data and suggested NVC classes. This shapefile contains the interpeted attributes and has been "crosswalked" with NVC codes (up to 3 per polygon).

300 ft upland buffer of the Cape Cod Commission's Pond Atlas Ponds.

This data set contains boundary layers for the Thacher Island National Wildlife Refuge in Massachusetts.

National Wildlife Refuges are federal lands managed by the U.S. Fish and Wildlife Service (USFWS). The primary source for boundary information is the USFWS Realty program (status maps, legal surveys). A joint effort between the Region 5 (northeast - ME, MA, NH, VT, RI, CT, NY, PA, NJ, MD, VA, WV) GIS Lab and Realty program, has resulted in digital refuge boundaries for all refuges in the northeast at a 1:24,000 scale.

The purpose of this data is to serve as a spatial reference of refuge boundaries for other data layers in GIS and mapping applications. It is specifically not intended to be used as a land survey or representation of land for conveyance or tax purposes. The Realty Survey program in USFWS is developing cadastral information (boundary and acreage data) appropriate for legal purposes. It is expected that data created in this project will be replaced as better survey information is collected.

Status maps were registered to geographic coordinates, boundaries digitized and labeled, then stepped through 3 levels of quality review for spatial and thematic accuracy.

Refuge boundaries define areas that are approved by U.S. Congress for acquisition in the National Wildlife Refuge System, or are currently owned by USFWS. Arcs are coded with an item "boundary" that the type of boundary line and polygons are coded with an item "status" that describes their ownership status.

[Summary provided by U.S. Fish

Massachusetts water features, including lakes, ponds, rivers, streams and wetlands. From USGS hydrography. For full metadata and links to download free data please visit https://www.mass.gov/info-details/massgis-data-massdep-hydrography-125000.

This EnviroAtlas dataset describes the percentage of each block group that is classified as impervious, forest, green space, and wetlands. Forest is a combination of trees and forest and woody wetlands. Green space is a combination of trees and forest, grass and herbaceous, agriculture, woody wetlands, and emergent wetlands. Wetlands includes both Woody and Emergent Wetlands. This dataset also includes the area per capita for each block group for impervious, forest, and green space land cover. This dataset was produced by the US EPA to support research and online mapping activities related to EnviroAtlas. EnviroAtlas (https://www.epa.gov/enviroatlas) allows the user to interact with a web-based, easy-to-use, mapping application to view and analyze multiple ecosystem services for the contiguous United States. The dataset is available as downloadable data (https://edg.epa.gov/data/Public/ORD/EnviroAtlas) or as an EnviroAtlas map service. Additional descriptive information about each attribute in this dataset can be found in its associated EnviroAtlas Fact Sheet (https://www.epa.gov/enviroatlas/enviroatlas-fact-sheets).

This Feature Service published by MassGIS represents Mouth of River (MOR) lines for Massachusetts coastal rivers originally published by the Massachusetts Department of Environmental Protection (MassDEP) on March 1, 2005 as PDF maps.The PDF maps identify the mouth of the river for coastal rivers in order to provide a clear, consistent, and predictable means of locating all river mouths in the Commonwealth. They are the final MOR maps for each community and represent the culmination of a year's effort that included distribution of draft maps for public comment, receipt and review of over 100 written comments, and field surveys for many of the more difficult mouth of river lines. Each Massachusetts coastal community received a set of maps corresponding to the rivers in their community.The MOR map lines are intended toidentify where a river ends pursuant to 310 CMR 10.58(2)(c). As provided in 310 CMR 10.58(2)(c) "When a river flows into coastal waters or an embayment, the river shall end at the mouth of coastal river line as delineated on the current mouth of coastal river map series maintained by the Department." represent the limit of Riverfront Area jurisdiction under the Wetlands Protection Act. Land upstream of the MOR line includes Riverfront Areas subject to the protections afforded by the Wetlands regulations; any land seaward of the MOR line is not subject to jurisdiction as a Riverfront Area but remains subject to other inland and coastal provisions of the Wetlands Protection Act. By adopting a uniform approach to mapping river mouths, this data should reduce the need for individual MOR delineations and in turn provide a predictable means for project review for landowners, conservation commissions and MassDEP.See full metadataAlso see the Map Service.

Polygon layer of wetlands within Wellesley. Combines Town created wetland layer with Massachusetts Department of Environmental Protection wetland layer.