{"data":{"id":"us/40-cfr-141.503","jurisdiction":"us","citation":"40 CFR 141.503","heading":"What does subpart T require?","body":"There are seven requirements of this subpart, and you must comply with all requirements that are applicable to your system. These requirements are:\n(a) You must cover any finished water reservoir that you began to construct on or after March 15, 2002 as described in §§ 141.510 and 141.511;\n(b) If your system is an unfiltered system, you must comply with the updated watershed control requirements described in §§ 141.520-141.522;\n(c) If your system is a community or non-transient non-community water systems you must develop a disinfection profile as described in §§ 141.530-141.536;\n(d) If your system is considering making a significant change to its disinfection practices, you must develop a disinfection benchmark and consult with the State for approval of the change as described in §§ 141.540-141.544;\n(e) If your system is a filtered system, you must comply with the combined filter effluent requirements as described in §§ 141.550-141.553;\n(f) If your system is a filtered system that uses conventional or direct filtration, you must comply with the individual filter turbidity requirements as described in §§ 141.560-141.564; and\n(g) You must comply with the applicable reporting and recordkeeping requirements as described in §§ 141.570 and 141.571.","path":["Title 40—Protection of Environment","CHAPTER I—ENVIRONMENTAL PROTECTION AGENCY","SUBCHAPTER D—WATER PROGRAMS","PART 141—NATIONAL PRIMARY DRINKING WATER REGULATIONS","Subpart T—Enhanced Filtration and Disinfection—Systems Serving Fewer Than 10,000 People"],"source_url":"https://www.ecfr.gov/api/versioner/v1/full/2026-08-25/title-40.xml","current_through":"2026-08-25","vintage":"","retrieved_at":"2026-08-27T02:26:04Z","sha256":"af4843fd8f3c92cee3331710670cf1b94a7342f9a38bec71f63a0bfe8f0554f7","source_id":"us-cfr","stale":true,"prev":"us/40-cfr-141.502","next":"us/40-cfr-141.510"},"notice":"GroundRules: Original legal text. Not legal advice."}