In this document, EPA is finalizing the Filter Backwash Recycling Rule (FBRR). The purpose of the FBRR is to further protect public health by requiring public water systems (PWSs), where needed, to institute changes to the return of recycle flows to a plant's treatment process that may otherwise compromise microbial control. Today's final rule addresses a statutory requirement of the 1996 Safe Drinking Water Act (SDWA) Amendments to promulgate a regulation which "governs" the recycling of filter backwash water within the treatment process of PWSs.