Section 141.152 - Compliance dates(a) Between June 24, 2024, and December 31, 2026, community water systems must comply with §§ 141.151 through 141.155 , as codified in 40 CFR part 141, subpart O, on July 1, 2023. Beginning January 1, 2027, community water systems must comply with §§ 141.151 through 141.156.(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.