A geographic information system (GIS) integrates hardware, software, and data for capturing, managing, analyzing, and displaying all forms of geographically referenced information.
GIS allows us to view, understand, question, interpret, and visualize data in many ways that reveal relationships, patterns, and trends in the form of maps, globes, reports, and charts.
A GIS helps you answer questions and solve problems by looking at your data in a way that is quickly understood and easily shared.
In a GIS, data is separated into various layers. This allows for layers to be combined on maps or in analysis as needed. For example, a simple street index map is very useful on its own, but by adding a single layer, such as voting precincts, and now you have a tool for identifying the voting precinct and location for any given street in Town, in an easy to use format.
GIS in Rockport
In the Town of Rockport, uses for GIS are still emerging, however common municipal uses include planning and zoning maps and data, public works infrastructure and asset mapping and management, conservation and wetlands mapping and data, and the ability to perform analysis of varying types for any combination of these layers as necessary.
What's the difference between Rockport's online GIS and other tools like Google Maps or Bing Maps?
Online tools like Google Maps or Bing Maps can be extremely useful, and each has their role to play. The main difference between these tools and Rockport's online GIS, Mapsonline, is that Rockport's GIS is based on Rockport's data. This is important because Rockport controls the quality and accuracy of Rockport's data, and in most cases, such as the aerial photography, Rockport's data will be more detailed than what is available from the other tools. The other viewers have unique tools that aren't available in other places, such as Google's StreetviewÂ® photography, or the oblique aerial imagery available through Bing. These can be useful tools, but are not always a substitute for the data that are, and will be, available through Rockport's Mapsonline GIS site or through paper or pdf maps available from the Engineering office.
Where does Rockport's data come from, and how is it updated?
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' office of GIS, 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.
Town layers will be 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 and data purchases, depending on the layer. Municipalities typically complete aerial photography projects on varying frequencies, but commonly cities and towns will conduct aerial photography projects on a 5-10 year interval depending on the rate of development in the community.