The GIS data used in Rockport's GIS come from multiple sources. Some of the more prominent layers came from aerial photography obtained in 2011, for the City of Gloucester, then offered to the Town by the firm that collected the photography. These layers include building footprints, infrastructure such as hydrants and catch basins, driveways, parking lots, and roads. Other layers are produced by the Town and updated by the Town as needed, such as the assessing parcels, zoning, and additional public works infrastructure layers. Finally, there are many layers available through the Commonwealth of Massachusetts' Executive Office of Technology Services and Security (EOTSS) GIS Department, or MassGIS. These include layers such as certified vernal pools and other Natural Heritage program data, scanned NOAA nautical charts, statewide (lower resolution) aerial imagery, environmental monitoring data, conservation and open space data, coastal and marine features, census and demographic data, political boundaries and regulated areas, and more.
The town's GIS data is updated as needed and as appropriate, using the best available sources. Data from the aerial photography will be updated either periodically by the Town, or through future aerial photography projects and data purchases. Municipalities typically complete aerial photography projects on varying frequencies, but commonly cities and towns will conduct aerial photography projects on a 5 to 10-year interval depending on the rate of development in the community.