MassDEP’s 11-17-2025 letter to MWRA Board

Based on the information presented at the October 29 meeting, MassDEP is concerned that Recommended Alternatives identified may be insufficient to address CSO discharges and associated impacts. In particular, an approach that would result in a greater number of activations and/or volumes than occur at present would not appear to be consistent with the federal Clean Water Act or the Massachusetts Surface Water Quality Standards, which are intended to “restore and maintain the chemical, physical, and biological integrity of the Nation’s waters.” 33 U.S.C. 1251(a); 314 CMR 4.01(3).