Section 141.152 - [Effective 12/30/2024] Compliance dates(a) Between June 24, 2024, and December 31, 2026, community water systems must comply with 40 CFR 141.151 through 141.155 (except § 141.153(d)(4)(xii) ), as codified on July 1, 2023. Beginning January 1, 2027, community water systems must comply with 40 CFR 141.151 through 141.156 (except § 141.153(8)(h)(i) ), as codified on July 1, 2024. Beginning November 1, 2027, community water systems must comply with 40 CFR 141.151 through 141.156 , as codified on July 1, 2025.(b) Each existing community water system must deliver reports according to § 141.155 by July 1 each year. Each report delivered by July 1 must contain data collected during the previous calendar year, or the most recent calendar year before the previous calendar year.(c) A new community water system must deliver its first report by July 1 of the year after its first full calendar year in operation.(d) A community water system that sells water to another community water system must deliver the applicable information required in § 141.153 to the buyer system: (1) By April 1, 2027, and annually thereafter; or(2) On a date mutually agreed upon by the seller and the purchaser, and specifically included in a contract between the parties; and(3) A community water system that sells water to another community water system that is required to provide reports biannually according to § 141.155(i) must provide the applicable information required in § 141.155(j) by October 1, 2027, to the buyer system, and annually thereafter, or a date mutually agreed upon by the seller and the purchaser, included in a contract between the parties.63 FR 44526, Aug. 19, 1998, as amended at 89 FR 46008 , May 24, 2024 89 FR 46008 , 6/24/2024; 89 FR 86662 , 12/30/2024