MA S608

Prohibits untreated combined sewer overflows in Massachusetts Water Resources Authority service areas beginning January 1, 2035, during 25-year 24-hour storm events or smaller storms

Defines "untreated" overflow as discharge lacking at least solids removal and bacteria deactivation treatment

Requires the Department of Environmental Protection to adopt implementing regulations within 18 months of enactment

Mandates DEP to define the 25-year 24-hour storm event standard and update it as climate changes

Adds new Section 27B to Chapter 21 of the General Laws governing environmental protection