The Regional Water Supply Planning Group (RWSPG) was created by the State of Illinois Department of Natural Resources (IDNR) to define a comprehensive program for regional water supply planning and management and to develop a strategic plan for its implementation. IDNR has commissioned and contracted with the Chicago Metropolitan Agency for Planning (CMAP) as its agent to organize, manage, provide technical assistance, and support and facilitate the overall project development of a regional water supply plan, as part of an emerging state plan, for northeastern Illinois.

The Defenders' have a representative on this group.