NLCD 2011 IC reference data
Excel files have percentage impervious cover estimates for the Chesapeake Bay region from 30 m  1 m data for six assessment units - 12-digit hydrologic units (watersheds), the riparian zones for the same watersheds, and four square lattices with cell sizes of 40, 2756, 5625, and 22500 ha.  There is an excel file for …