# Spatial Data

The Zoning Atlas has spatial data for the base zoning districts of the 101 municipalities in the MAPC region, and, as of December 2020, spatial data for 272 overlay districts across 60 municipalities. Once comprehensive, the spatial data for overlay districts may never include all municipalities in the MAPC region, as some municipalities may not use overlay districts.&#x20;

Most of the spatial data in the Zoning Atlas was provided by representatives of municipalities in the MAPC region, following outreach by MAPC. These data are supplemented with spatial data that we were able to independently download through an open data portal on the municipality’s website and with data from internal files from past planning projects with that municipality. MAPC used spatial data collected by MassGIS in 1999 when these three pathways did not yield spatial data for base zoning districts (ten municipalities), or when municipal representatives confirmed that more recent data did not exist (six municipalities). &#x20;

As there was no parallel historical data for overlay zoning districts, the Zoning Atlas only has the overlay data we were able to retrieve. MAPC did augment municipal-level spatial data with statewide spatial data for 40R Smart Growth Zoning Overlay Districts, which were provided to MAPC by the Department of Housing and Community Development (DHCD) in March 2020. (DHCD’s 40R spatial data is current to 2017.) The 40R spatial data provided partial overlay data for four municipalities and 12 overlay zones where we didn’t previously have data.&#x20;

The Date Spatial Data Received (`SPATIALREC`) field in the tabular data describes the date MAPC staff first accessed the spatial data published to the Atlas. &#x20;
