- This layer represents the eight mega-drainage basins for Massachusetts, aggregated from the Major Basins layer. The delineations were based on the level 2 Hydrologic Unit Codes (HUCs) from the U.S. Geological Survey. Included are delineation of the Narragansett and Thames mega-basins. The polygon layer is named MEGABASINS_POLY.
- Held by
- More details at
|Click on map to inspect values|