Massachusetts Maps

The Nature Conservancy assessed spatial data resources for Massachusetts’ ocean and coastal lands in 2007 and 2010. The 2007 report, Looking at Massachusetts’ Tidelands: An Assessment of Spatial Data on Tidelands Ownership, Licensing, Jurisdiction, and Protection (download pdf, 2,117k), reviews the available data in detail. During the 2007 assessment, TNC obtained or created spatial data that is not currently available through the web (these are noted below). Please Contact Us if you would like access to this data. Information from the 2010 assessment is included below.

Digital Data Availability Summary

Click for local parcel information. Map courtesy Digital Map Store

Why is marine cadastral data important for conservation and marine spatial planning?

Marine Cadastral Data Management

The Nature Conservancy’s 2010 Nationwide Comparative Assessment of State-level Marine Cadastral Data in Massachusetts included a review of relevant Internet sites and an interview with the and an the Massachusetts Coastal Zone Management Office (CZMO). The CZMO also completed an inventory (pdf) of state-level marine cadastral data.1

State Data Management: The Massachusetts Office of Geographic Information is statutorily responsible for developing, maintaining, updating and distributing geographic information, technology, data and services for use by state agencies, municipalities and the public. They maintain the state portal for geospatial data that provides data downloads and online mapping tools known as MassGIS. The CZMO provides an online mapping tool, the Massachusetts Ocean Resource Information System (MORIS) that is focused on the coastal and marine areas. Although it was designed for coastal management professionals it can be used by anyone to create, share maps and download the data.

Marine Cadastre and Supporting Data

Cadastral Reference System: Massachusetts does not have a marine cadastre although they created 1000m and 250m marine grids for the Massachusetts Ocean Management Plan. The purpose of the grid is to:

• Locate (approximately) marine resources with a built-in buffer zone
• Align other gridded data to these grids
• Use for grid-based analysis
• Index underlying data to the grid to be used as a lookup tool for energy or other development proposals

Supporting Reference Data: MORIS provides a compilation of coastal management data that can be viewed online and downloaded. The MassGIS site provides a metadata listing of all published agency data (http://www.mass.gov/mgis/laylist.htm#consres) categorized by various features. Of principal interest is the Coastal and Marine feature list, which includes a separate listing of the MORIS data. This is a list of metadata that describe the layers in MORIS and can be downloaded from MassGIS.

Coastal Imagery: Coastal imagery is available from both MassGIS and MORIS, including 1 foot Coastal Color Orthophotos.

Shorelines and Bathymetry: Shorelines and bathymetry are available from both MassGIS and MORIS.

Marine Jurisdictional and Submerged Lands Boundaries: It is important to note that lateral boundaries are not known or adjudicated between Massachusetts, New Hampshire and Rhode Island. The seaward extent of town jurisdictions as well the lateral boundaries between jurisdictions is not well defined. Under the Wetlands Protection Act, some lines of jurisdiction relate to bathymetry. Jurisdictional data is available from MassGIS and MORIS. The submerged lands boundary area is not described but it can be derived from the shorelines and the state 3nm boundary.

Ownership: The state owns most tidelands below the MLW or 1,650 ft from MHW, whichever is more landward. There may be exceptions created by old grants and legislative wharfing statutes. Privately owned parcels may be found in some town assessor maps. MassGIS has partial compilation of town parcel data (not tideland specific). The accuracy of the submerged lands parcels is questionable.

Leases and Other Authorizations: The Massachusetts Department of Environmental Protection’s waterways program manages leases in coastal waters. Lease data is held in-house, but the MORIS site identifies lease areas.

Marine Managed Ares: The MassGIS and MORIS sites provide a listing of the state’s marine managed areas and conservation lands.

Local Parcel Information: MassGIS has a partial list of town parcel data. As MassGIS has yet to institute a system for receiving updates on a regular basis, they suggest that users contact the individual municipalities for the most current data (see Local Parcel Information, below).

GIS Portals

• MassGIS, the Commonwealth’s Office of Geographic and Environmental Information (web site). Download or order data, view metadata, and use online interactive maps.
• Massachusetts Ocean Resource Information System (MORIS) (web site). Provides online mapping and downloads of the state's marine coastal data.

Reference and Supporting Data

Cadastral Reference Grid

Shorelines

Coastal Imagery

Bathymetry

Marine Jurisdictional Boundaries

Submerged Lands Boundaries

The Nature Conservancy developed a polygon representing Massachusetts flowed tidelands, using a NOAA mean high water shoreline, the most recently surveyed state-federal marine boundary from the Minerals Management Service, and coordinates for the marine boundaries with New Hampshire and Rhode Island provided by the Massachusetts Highways Department. Approximations may also be derived from the following data layers available online, although the seaward boundary will not reflect the most recent surveys.

Ownership

Submerged Lands Parcels

General Property and Parcel Data

Public and Conservation Lands

Leases and Other Use Authorizations

Aquaculture and Shellfish

Other Use Authorizations

Marine Managed Areas

Local Parcel Information

A number of Massachusetts’ counties no longer have county government. Most local authority lies with cities and towns, and the administrative functions of some counties have reverted to the state.

Coastal Registry Districts

Coastal Regional Planning Agencies

Coastal Municipalities

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