GIS For Hamilton

The Town of Hamilton is publicly releasing its first GIS, provided by CAI Technologies. This new, easy-to-use GIS will increase the availability of public information such as assessors data and land use regulations for both town employees and the general public.

What is GIS?

A Geographic Information System (GIS) is the integration of hardware, software, and data used to visualize or analyze spatially referenced information. GIs allows users to visualize, interpret and understand data in many ways that reveal relationships, patterns and trends in the form of maps.

What Type of Information Is Available?

There is a variety of information available including Areas of Interest, Assessors Information and Map Layers among others. The Town will continue to add and update information as it becomes available. The Assessors Office On-line Assessment Database is still available on Hamilton’s Website on the Assessors’ page (www.hamiltonma.gov).

Using the Online GIS System

There are a variety of useful tools integrated into the GIS environment.


Users can locate parcels in Hamilton by owner names, addresses, or parcel ID’s. To search, enter an owner, address or parcel ID, click the button Find Owner, Find Address or Find Parcel ID with the mouse. If there is a name, address, or ID containing the entered text, it will be listed beneath the search box, with data fields for parcel ID, owner, address, and CAMA ID. On the map, pushpins will appear marking each parcel meeting the search description. By clicking on a “row” beneath the search results, the map will pan and zoom in on the selected parcel.

Results Tools

In addition, after performing a search, Results Tools will become available. By clicking Add/Remove Selected, one can add or remove individual parcels from the report or mailing list by clicking them on the map at right. Included parcels will be marked by the pushpins. The Report and Mailing Labels buttons will generate easy-to-print pdf files based on the search results. Please note: Pursuant to Massachusetts General Laws, Chapter 40A, Section 11 any abutters lists created by the Public are not deemed certified unless created by the Assessors Office.

Areas of Interest section

Currently there are seven areas of interest listed. Clicking on any name in the areas of interest section will pan and zoom the map to the landmark.

Map Layers section

Here, the user can pick and choose which maps appear to the right. By default, only most layers of the town base map are visible. To add layers, simply check off the box to the left of their name. If the layer is a subsection of another set of layers, the larger set will have to be checked off as well. For instance, under Political/Administration is a layer called Municipal Zoning Districts. To view the zoning district map layer, both Municipal Zoning Districts and Political/Administration would have to be checked off. Conversely, users can remove map layers by unchecking the box to the left of the layer. Over time, map layers may be updated, or new map layers may become available.

Map Details

This section is only usable when a parcel is selected, either from a row in search results, or using the Identify tool. The Identify tool is on the toolbar on the top of the map, represented by “i”. After selecting the identify tool, click on any parcel and it will appear under Map Details. Also included under Map Details are Abutters Tools, Property, Data and Property Card Information.

Abutters Tools

Abutters Tools can be used to draw a region around the parcel, measured in feet, and generate reports or mailing labels for parcels at least partially in that region. Similar to in the Find section, one can use Add/Remove Selected to manually include or exclude parcels from the generated report or list. Please note: Pursuant to Massachusetts General Laws, Chapter 40A, Section 11 any abutters lists created by the Public are not deemed certified unless created by the Assessors Office.
Property … Displays the chosen parcel.
Data………. One can select whether they want to view the property documents from the assessors database, a brief table of assessment data, or a brief table of building data for the selected parcel. Clicking Property Card will cause it to pop up in a new window. You may print a field card from here as well. Bing Maps provide the option of a bird’s eye perspective.
Help section assists in navigating GIS. Users can choose what kind of base map they would like: Relief, USGS, aerial, or parcel. By default, users see relief. The Zoom In and Zoom Out tools can be clicked and dragged to draw boxes around where the map should zoom. The hand represents a panning tool, which can be dragged to move your view across the map. There are Previous Extent and Next Extent tools, represented by arrows, which allow the user to quickly switch between previous views of the map. The globe icon represents the Full Extent tool, which zooms out and pans to view the entire town. The blank sheet of paper represents the Clear Selected tool, which simply removes any results from the Find or Abutters Tools. The printer icon represents the Print tool, which generates an easy-to-print pdf of the current map view based on desired titles, scale, map quality, and print template. Last on the bar are the graphic and measuring tools. The Graphics Tools can be used to add a variety of markings to the map such as points, lines, polygons, common shapes, text and freehand drawings. The Measuring Tools can measure distance along a path of lines or areas contained in a polygonal region.