![]() ![]() Some municipal boundary arcs (about 15% of the total) follow the edge of a road or rail right-of-way or a stream or river channel. The differences between the municipal boundary arcs digitized from those on the USGS quads and those created by snapping to the survey-derived coordinates are typically plus or minus 12 feet, although these differences are sometimes less and sometimes more. Boundary arcs from the existing USGS-derived municipal boundary data layer were then snapped to the survey-derived points. MassGIS used the state plane coordinates to "generate" points in ArcGIS. Staff from the Survey Section then converted the latitude/longitude coordinates to the NAD83 datum and also created a version of the coordinates in state plane coordinates with units of meters. MassGIS staff keyed the coordinates into a database that data entry was double-checked by staff from the Survey Section. ![]() MassGIS staff collaborated closely with staff from the Survey Section during the development of this data layer. The Atlas series was published in the early 1900s and has since been updated by the Survey Section of the Massachusetts Highway Department with changes as they are approved by the legislature. The original surveys were conducted in the 1890s. The Atlases also include detailed descriptions of each community's boundary and location maps for each of the original boundary marker locations. Each survey was tied into higher order monumented survey control points. These coordinates were recorded from surveys of the location of each boundary marker around the periphery of each community. This Atlas series, and updates since it was published, describes the legal boundary for each of the 351 municipalities in Massachusetts. This political boundary datalayer has been created from latitude and longitude coordinates found in the 68-volume Harbor and Lands Commission Town Boundary Atlas. MassGIS Data - Community Boundaries (Towns) from Survey Points (geonode:massgis_data_community_boundaries_towns_4bt)
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