Groundwater adjudication.

The document was reformatted from the official chaptered legislative format (with page numbers, 'Ch. 643' headers, and formal layout) to a web page presentation that includes navigation menus, search tools, version history links, and other website interface elements. The underlying bill text is unchanged.

Section 845(d)(1) now requires GSA technical reports only 'if the agency is able to do so at a reasonable effort and expense.' This gives GSAs an out if preparing the report would be disproportionately burdensome, making the reporting obligation conditional rather than absolute.

Section 840(c) expands the court's obligation when exempting or separately treating minor claimants from merely establishing 'a procedure to register such claims' to establishing 'an appropriate procedure for the registration and administration of such claims,' giving the court a broader mandate over how those claims are handled going forward.

New Section 845(d)(3) allows a GSA to file a noticed motion (with at least 10 days notice) for interim or partial payments of its report-preparation expenses from the parties while the report is still being prepared. Previously, GSAs could only seek full reimbursement after completing the report.

Section 842(d)(1) changes the small-claimant disclosure presumption threshold from 'less than an average annual extraction of 100 acre-feet' to 'not more than 100 acre-feet of water per year.' This means a party extracting exactly 100 acre-feet now qualifies for the presumption that its disclosed facts are accurate, shifting the burden to any challenger.

Section 833(d)(2) changes 'separately processing and entering judgments' to 'separately processing and entering orders' for minor claimants treated separately. This is a procedural change that may affect the finality and enforceability of dispositions for small water users.

Header changed from the enrolled bill format (with passage dates, clerk signatures, and receipt-by-governor language) to the chaptered law format showing 'STATE OF CALIFORNIA AUTHENTICATED ELECTRONIC LEGAL MATERIAL,' Chapter 643, and the Governor's approval date of October 11, 2025.

Page headers changed from 'AB 1466' to 'Ch. 643' and page numbers shifted from starting at 94 to starting at 93, reflecting re-pagination in the official statutes.

Line wrapping and spacing throughout the statutory text was adjusted to fit the chaptered format's wider layout, but the actual legal language of Sections 833, 840, 842, and 845 of the Code of Civil Procedure is unchanged.

New provisions in Section 833 clarify when comprehensive adjudication applies and list four exceptions (interference-only actions, specific recharge source claims, limited-party actions, and already-adjudicated areas). Also allows courts to join surface water claimants when necessary for fair determination of groundwater rights.

Section 833(d) gives courts a new option beyond simply exempting minor-quantity claimants (5 acre-feet or less per year): they can now treat those claimants separately from other parties by processing and entering separate judgments, reducing their participation burden. A hearing is required to decide between exemption and separate treatment, and the court must establish a registration procedure.

Entirely new Section 840 requires case management conferences in all comprehensive adjudications. For basins requiring a groundwater sustainability plan under SGMA, the court must manage the case per Water Code Section 10737.2. The initial conference may address boundary adjustments, stays, special masters, preliminary injunctions, phasing of issues, discovery limits, early resolution of prescriptive rights, and class formation for overlying rights holders.

Entirely new Section 842 requires parties to serve initial disclosures within six months of appearing, covering 12 categories including 10 years of extraction data, well locations, crop types, surface water rights, and replenishment activities. Disclosures must be verified under penalty of perjury and served electronically when possible.

Section 842(d) creates a presumption of accuracy: if a party claims less than 100 acre-feet average annual extraction (or an amount the court deems reasonable), the court must presume those facts are accurate. Any party challenging those facts bears the burden of proving inaccuracy. This shifts the evidentiary burden away from small extractors.

Section 845(d)(1) updated to reference 'parties excused or treated separately' under Section 833(d), reflecting the new separate-treatment option for minor-quantity claimants in the technical report provision.

Fiscal committee approval changed from 'no' to 'yes,' indicating the bill now has fiscal implications requiring committee review, likely due to the new disclosure and case management requirements imposing costs on courts and parties.

Removed new Section 844.5 (Article 11.5) which would have required any party seeking judicial review of a groundwater sustainability agency action taken under an approved groundwater sustainability plan to meet the substantial evidence standard of proof in a groundwater adjudication. This provision would have made it more difficult for parties to challenge GSA decisions in court.

Fixed drafting errors in Section 842: corrected 'the purpose to for which the groundwater has been put. used' to 'the purpose for which the groundwater has been used' and similar garbled text in paragraph (6).

Updated gender-neutral language in Section 842(f): changed 'his or her their' to simply 'their' when referring to a party serving disclosures electronically.

Restructured sentence in Section 845(d)(2) from 'If the groundwater sustainability agency provides a report, the agency shall not be entitled to a fee' to 'If A groundwater sustainability agency that provides a report, the agency (1) shall not be entitled to a fee' with added paragraph numbering.

The bill now amends Section 845 of the Code of Civil Procedure in addition to adding Article 11.5, substantially broadening the bill's reach into court procedures for groundwater adjudication.

Section 844.5(a) now specifies that the burden of proof uses a 'substantial evidence standard of review,' clarifying the legal threshold for judicial review of agency actions.

New Section 845(d) requires courts in basins with DWR-approved GSA plans to request that the groundwater sustainability agency provide a technical report quantifying and describing groundwater use of parties who have not appeared before the court. The report is prima facie evidence of physical facts but may be rebutted.

Applicability was narrowed: the burden-of-proof provision now applies only to actions taken under plans that have been approved by the Department of Water Resources, not merely adopted after January 30, 2020. The word 'only' was also added for emphasis.

New Section 845(d)(2) provides that the GSA is entitled to reimbursement of total expenses (salaries, wages, travel, all costs) for providing the technical report, with no fee. The court apportions these costs among parties in an equitable manner.

New Section 845(a)-(c) establishes special master provisions: courts may appoint special masters to investigate technical and legal issues, conduct joint factfinding, develop preliminary injunction proposals, and perform other tasks. The State Water Resources Control Board or DWR may recommend candidates or review qualifications.

New Section 845(e)-(f) preserves the court's existing authority to make references under the Water Code and to appoint watermasters, ensuring the new provisions do not limit existing judicial powers.