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Statewide basemapping

In order to support public safety and many other mapping needs, MassGIS has focused on developing four key data layers.

Statewide basemapping from MassGIS

MassGIS has developed a number of multi-purpose map layers that can integrate into an existing community GIS or even serve as a foundation for a new system. These layers are shown below – collectively they are known as Massachusetts Spatial Data Infrastructure or MSDI. The standards and specifications for MSDI were set through a collaborative process involving state, regional and municipal GIS users and work has been ongoing since 2010.

A portion of the funding for this effort came from the Executive Office of Public Safety and Security (EOPSS) to support the next generation of 911 technology, which will use GIS-based addressing for call routing and dispatch. Other state agencies with GIS are contributing as well to MSDI. These layers are being assembled by MassGIS staff and a team of vendors at the state level, but that isn’t the end of the story. We need local review to ensure that they as accurate as possible, and we need local input to maintain them. Once the new 911 technology rolls out, this on-going maintenance will be a critical public safety need.

MSDI diagram

The table below describes the overall project – by the end of phase II, data will be ready for the new 911 systems.

Phase Status Accuracy / completeness
I – FY13 Completion of first round for all MSDI layers based on available information – aerial imagery, local assessor tax maps and various address listings 99.5% or better
II – FY14 Collaborative review and field work, engaging Regional Planning Agencies (RPAs) and local officials to fill in gaps and fix any errors 99.95% for addressing
III – FY14+ Ongoing maintenance by communities with regional support real-time

Working with MassGIS to keep MSDI current

MassGIS and its RPA partners want to engage your community in the collaborative development and maintenance of the MSDI layers. Here are the specifics for each layer:

  1. Orthophoto – Commercial 2011 imagery from Digital Globe has been commissioned and licensed by MassGIS for all levels of government in Massachusetts.  This imagery can be viewed using the Microsoft Bing service; for special applications the actual image data can be obtained directly from MassGIS.   The plan is to re-fly non-urban areas for imagery in the spring of 2014.  Some communities may wish to acquire higher resolution imagery – six-inch or even three-inch pixels instead of the one-foot resolution for Digital Globe.  The MassOrtho Consortium is taking the lead in organizing communities to jointly acquire 4-band digital imagery at higher resolution, regardless of their USGS designation of Urban or non-urban. In the spring of 2013, the USGS flew the urban areas of: metro Boston (roughly the counties of Essex, Middlesex, Suffolk, Norfolk and the northern "halfs" of Plymouth and Bristol), Worcester and Springfield.
  2. Streets – There are two statewide street maps in GIS.   One was created by MassGIS and the Department of Transportation (DOT) for planning purposes.  The other is licensed from a commercial provider, NAVTEQ, to support geocoding, which means that it has address ranges linked to street segments.  An effort is underway at DOT to merge these two datasets, which will provide better linework and still allow for geocoding use by government users.  MassGIS sends update requests quarterly to NAVTEQ to ensure that the geocoding dataset is as current and complete as possible – almost 6,000 streets have been added over the life of the project and 250,000 records have been edited.  MassGIS has also compiled a master list of “official” street names using new national standards for addressing.  We are seeking local review of this list and would urge local adoption of the address standards.  In addition, we are asking local officials, using web-based map editing tools, to help us locate the few remaining streets in the master list which have not been mapped (some of them may just be “paper” streets that were never built.) 
  3. Parcels – A standardized, seamless, statewide tax parcel layer from local mapping sources was completed in the fall of 2013.  Each parcel has been linked to one or more tax records listing owner name, value of land and buildings, use of the property and other common assessing attributes.  This will provide MassGIS users and 911 with more accurate address locations, but it will also support many other state agency goals - facility management, land conservation, economic development, transportation planning, assessment of flood hazard and many other uses.   MassGIS is urging communities to adopt the Level III standard in maintaining local parcel mapping going forward.   Sometimes this will require an additional investment to transfer customized features of pre-existing local mapping to the new statewide map, however the quality of the resulting product, and the ability to share it with other GIS users, make this a worthwhile step. 
  4. Building roofprints and address project – “Roofprints” now exist for the whole state – about 2.4 million building roof outlines from orthophotography. The ultimate goal of our addressing project for 911 is to link a standardized form of every numbered address in the Commonwealth, and if needed additional detail like the building name, to points derived from roofprints.  Local and regional involvement will be critical in completing this project.  The parcels provide an initial, draft version of the address; points with no address, addresses with no matching point and addresses where more detail is needed will be investigated in the field.  Our plan is to have regional planning agencies assist communities in doing this field work, using mobile data collection devices (wireless tablets) to link to the MassGIS server.  We recognize that many communities have created their own address point datasets – and we are ready to take on the effort of synchronizing those with the statewide effort if the community will commit to maintenance going forward.   The key, as with the parcels, is adoption of the standards for addressing, and local capacity to track address changes on an ongoing basis. 


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