California moves to adopt federal Lead and Copper Rule Improvements ahead of 2027 compliance date

California officials on Wednesday explained how the State Water Resources Control Board's Division of Drinking Water plans to adopt the federal Lead and Copper Rule Improvements (LCRI) into state regulation and to seek primacy from the U.S. Environmental Protection Agency so the state can enforce the rule by the federal compliance date of Nov. 1, 2027.

The Division presented a proposed regulation text that largely mirrors federal LCRI language, with only "nonsubstantive" formatting and California-specific clarifications, and said it intends to use an expedited (emergency) adoption pathway under California Health and Safety Code section 116365.03. Officials said adopted state regulations cannot be more stringent or materially different than federal requirements.

Wes Steringer Cisneros of the Division of Drinking Water described the planned rulemaking schedule: public comment on the draft regulation runs through June 22, 2026, the agency will present a summary of comments to the board in August 2026, and the Division aims to submit adopted regulations to the Office of Administrative Law later this year so EPA can review California's primacy application before the 2027 compliance date.

Why it matters: If California secures primacy, the Division of Drinking Water will replace EPA as the primary enforcement authority for lead-and-copper requirements in the state. Officials said that taking early action will reduce the chance of dual enforcement by the state and EPA.

What the proposed state text does: Presenters said they copied federal LCRI text into California format and made non-substantive edits such as renumbering, clarifying dates (for example, setting the Nov. 1, 2027 compliance date explicitly in the state text), and omitting federal provisions inapplicable to California. The new LCRI provisions will appear primarily in a new chapter 17.6 of title 22, division 4, of the California Code of Regulations.

Implementation and next steps: Division staff said they will publish guidance and provide trainings throughout 2026 and 2027 to assist water systems with inventory validation, sampling plans and other compliance steps. The public comment period is open through June 22, 2026; comments should be submitted in PDF format to commentletters@waterboards.ca.gov with the subject line "Control of lead and copper regulation and AB1096 policy handbook."