Connecticut Data Sources List of GIS data sources for Connecticut. Geo Portals Connecticut https://portal.ct.gov/DEEP/GIS-and-Maps/Maps/Maps-and-GIS-Data Portal Link Connecticut https://ct-deep-gis-open-data-website-ctdeep.hub.arcgis.com/ Portal Link Connecticut https://connecticut-ctdot.opendata.arcgis.com/ Portal Link Connecticut https://cteco.uconn.edu/ Portal Link Rest Services