AMENDED IN SENATE SEPTEMBER 4, 2025

AMENDED IN SENATE JULY 17, 2025

AMENDED IN SENATE JUNE 26, 2025

AMENDED IN ASSEMBLY APRIL 1, 2025

CALIFORNIA LEGISLATURE— 2025–2026 REGULAR SESSION

93

CHAPTER 643

Statutes of 2025

[ Approved by Governor October 11, 2025. Filed with Secretary of State October 11, 2025. ]

Introduced by Assembly Member Hart

February 21, 2025

An act to amend Sections 833, 840, 842, and 845 of the Code of Civil Procedure, relating to groundwater adjudication.

Vote: majority   Appropriation: no   Fiscal committee: yes   Local program: no

LEGISLATIVE COUNSEL’S DIGEST

(1) Existing law establishes procedures for the comprehensive adjudication of groundwater rights in civil court. Under existing law, if the court finds that claims of right to extract or divert only minor quantities of water, as defined, would not have a material effect on the groundwater rights of other parties, the court may exempt those claimants from the proceedings, except as specified. Existing law further prescribes that a judgment in a comprehensive adjudication to determine rights to extract groundwater in a basin is not binding on, among others, claimants whose claims have been exempted.

This bill would authorize a court, in lieu of the exemption process described above, to treat persons with claims of right to extract or divert only minor quantities of water separately from other parties to the comprehensive adjudication. The bill would require the court to hold a hearing within a specified time to determine whether to exempt or treat those claimants separately and to establish a procedure to register and administer such claims.

(2) Existing law, in a comprehensive adjudication of groundwater rights in civil court, requires a party to serve on the other parties and the special master, if appointed, an initial disclosure that includes certain information within six months of the party’s appearance in a comprehensive adjudication, except as specified. Existing law requires that information to include a description of the general purpose for which the groundwater has been used and the area in which the groundwater has been used.

This bill would require the court to presume the accuracy of the facts asserted by a party in the initial disclosure described above if the party claims an annual extraction of not more than 100 acre-feet of water. The bill would provide that a party who challenges the facts asserted in an initial disclosure that qualifies for this presumption has the burden of proving the inaccuracy of those facts. The bill would, if the groundwater has been used for an agricultural use, require the initial disclosure to include information regarding the type of crops grown and the number of acres irrigated during the preceding 10 years.

(3) Existing law, the Sustainable Groundwater Management Act, requires all groundwater basins designated as high- or medium-priority basins by the Department of Water Resources to be managed under a groundwater sustainability plan or coordinated groundwater sustainability plans, except as specified. Existing law authorizes any local agency or combination of local agencies overlying a groundwater basin to decide to become a groundwater sustainability agency for that basin and imposes specified duties upon that agency or combination of agencies, as provided.

This bill would require the court to, in any adjudication in a basin where one or more groundwater sustainability agencies have adopted a groundwater sustainability plan that has been approved by the department, request that the groundwater sustainability agency provide a technical report, to the extent that the agency is able to do so at a reasonable effort and expense. The bill would require such a report to, at a minimum, quantify and describe the groundwater use of parties that have not otherwise appeared before the court, as provided. The bill would provide for the payment or reimbursement of costs related to the technical report, as provided. The bill would permit the court during the pendency of the report to award interim or partial payments to be made by the parties, upon a motion with proper notice, as specified, by a groundwater sustainability agency, and following a hearing. The bill would provide that the technical report shall be prima facie evidence of the physical facts found in the report, as provided.

The people of the State of California do enact as follows:

SECTION 1.

Section 833 of the Code of Civil Procedure is amended to read:

833.

(a) Except as provided in subdivision (b), this chapter applies to actions that would comprehensively determine rights to extract groundwater in a basin, whether based on appropriation, overlying right, or other basis of right.

(b) This chapter does not apply to any of the following:

(1) An action that concerns only allegations that a groundwater extraction facility, or group of facilities, is interfering with another groundwater extraction facility or facilities and does not involve a comprehensive allocation of the basin’s groundwater supply.

(2) An action that concerns only claims to extract, or to prevent interference with extractions of, a specific source of groundwater recharge and does not involve a comprehensive allocation of the basin’s groundwater supply.

(3) An action that can be resolved among a limited number of parties and does not involve a comprehensive determination of rights to extract groundwater within the basin.

(4) An adjudicated area described in subdivisions (a) to (d), inclusive, of Section 10720.8 of the Water Code, unless a court with jurisdiction over a proposed expansion of the adjudicated area orders that the proceeding be conducted in accordance with this chapter.

(c) If the court finds that including an interconnected surface water body or subterranean stream flowing through known and definite channels is necessary for the fair and effective determination of the groundwater rights in a basin, the court may require the joinder of persons who claim rights to divert and use water from that surface water body or subterranean stream in a comprehensive adjudication conducted pursuant to this chapter.

(d) If the court finds that claims of right to extract or divert only minor quantities of water, not to exceed five acre-feet of water per year, would not have a material effect on the groundwater rights of other parties, the court may do either of the following:

(1) Exempt those claimants with respect to those claims for only minor quantities of water, but a person who is exempted may elect to continue as a party to the comprehensive adjudication.

(2) Treat those claimants separately from other parties to the comprehensive adjudication by separately processing and entering orders with respect to those persons, in order to reduce their burden of participation and more efficiently administer the case.

SEC. 2.

Section 840 of the Code of Civil Procedure is amended to read:

840.

(a) In managing a comprehensive adjudication, the court shall do both of the following:

(1) Convene a case management conference as provided by the California Rules of Court.

(2) In an adjudication action for a basin required to have a groundwater sustainability plan under the Sustainable Groundwater Management Act (Part 2.74 (commencing with Section 10720) of Division 6 of the Water Code), manage the case in accordance with Section 10737.2 of the Water Code.

(b) In an initial case management conference, or as soon as practicable, the court may consider the following in addition to other matters:

(1) Determining whether to seek adjustment of the basin boundaries pursuant to Section 841.

(2) Staying the action pursuant to Section 848.

(3) Appointing a special master pursuant to Section 845.

(4) Scheduling a hearing on a preliminary injunction pursuant to Section 847.

(5) Dividing the case into phases to resolve legal and factual issues.

(6) Issuing orders to ensure that issues resolved in one phase are not relitigated in another phase.

(7) Limiting discovery to correspond to the phases.

(8) Scheduling early resolution of claims to prescriptive rights.

(9) Forming a class or classes of overlying groundwater rights holders pursuant to the criteria specified in Section 382.

(c) After a plaintiff files with the court a notice of completion of the mailing required by Section 836, the court shall, as soon as practicable, hold a hearing to determine whether to exempt or treat separately those claimants who extract or divert only minor quantities of water, as described in Section 833. If the court determines that certain claimants shall be exempted from, or treated separately from, other parties, the court shall establish an appropriate procedure for the registration and administration of such claims.

SEC. 3.

Section 842 of the Code of Civil Procedure is amended to read:

842.

(a) Except as otherwise stipulated by the parties or ordered by the court, within six months of appearing in a comprehensive adjudication, a party shall serve on the other parties and the special master, if one is appointed, an initial disclosure that includes all of the following information:

(1) The name, address, telephone number, and email address of the party and, if applicable, the party’s attorney.

(2) The quantity of any groundwater extracted from the basin by the party and the method of measurement used by the party or the party’s predecessor in interest for each of the previous 10 years preceding the filing of the complaint.

(3) The type of water right or rights claimed by the party for the extraction of groundwater.

(4) A general description of the purpose for which the groundwater has been used, and if for an agricultural use, the type of crops grown during each of the 10 calendar years immediately preceding the filing of the complaint.

(5) The location of each well or other source through which groundwater has been extracted.

(6) The area in which the groundwater has been used, and if for an agricultural use, the number of acres the party irrigated during each of the 10 calendar years immediately preceding the filing of the complaint.

(7) Any claims for increased or future use of groundwater.

(8) The quantity of any beneficial use of any alternative water use that the party claims as its use of groundwater under any applicable law, including, but not limited to, Section 1005.1, 1005.2, or 1005.4 of the Water Code.

(9) Identification of all surface water rights and contracts that the party claims provides the basis for its water right claims in the comprehensive adjudication.

(10) The quantity of any replenishment of water to the basin that augmented the basin’s native water supply, resulting from the intentional storage of imported or non-native water in the basin, managed recharge of surface water, or return flows resulting from the use of imported water or non-native water on lands overlying the basin by the party, or the party’s representative or agent, during each of the 10 calendar years immediately preceding the filing of the complaint.

(11) The names, addresses, telephone numbers, and email addresses of all persons possessing information that supports the party’s disclosures.

(12) Any other facts that tend to prove the party’s claimed water right.

(b) The Judicial Council may develop a form for initial disclosures made pursuant to subdivision (a) to facilitate the consistent, independent, impartial, and accessible administration of comprehensive adjudications. The Judicial Council may coordinate with the department in developing the form.

(c) A party shall make its initial disclosures based on the information then reasonably available to it. A party is not excused from making its initial disclosures because it has not fully investigated the case, because it challenges the sufficiency of another party’s disclosures, or because another party has not made its disclosures.

(d) (1) If a party claims in an initial disclosure to extract not more than 100 acre-feet of water per year, as required by paragraph (2) of subdivision (a), the court shall presume the accuracy of the facts asserted in the initial disclosure.

(2) A party who challenges the facts asserted in an initial disclosure described in paragraph (1) has the burden of proving the inaccuracy of those facts.

(e) A party that has made its initial disclosures, as described in subdivision (a), or that has responded to another party’s discovery request, shall supplement or correct a disclosure or response in all of the following situations:

(1) In a timely manner if the party learns that in some material respect the disclosure or response is incomplete or incorrect and the additional or corrective information has not otherwise been made known to the other parties during the disclosure or discovery process.

(2) If the party extracts groundwater from the basin after the complaint is filed. A supplement filed pursuant to this paragraph shall report the quantity of water extracted and be filed within 90 days after the end of the calendar year.

(3) As ordered by the court.

(f) To the greatest extent possible, a party shall serve their initial disclosures electronically. If it is not possible for the party to serve their disclosures electronically, the party shall serve the disclosures in an electronic format saved on a portable storage media device such as a compact disc or flash drive.

(g) A party’s obligations under this section may be enforced by a court on its own motion or the motion of a party to compel disclosure.

(h) A party’s disclosures under this section shall be verified under penalty of perjury as being true and correct to the best of the party’s knowledge.

SEC. 4.

Section 845 of the Code of Civil Procedure is amended to read:

845.

(a) The court may appoint one or more special masters whose duties may include the following:

(1) Investigating technical and legal issues, as directed by the court. The special master shall compile a report of findings in accordance with Section 846.

(2) Conducting joint factfinding with the parties, their designees, or both.

(3) Investigating the need for, and developing a proposal for, a preliminary injunction pursuant to Article 13 (commencing with Section 847).

(4) Performing other tasks the court may deem appropriate.

(b) The court shall fix the special master’s compensation on the basis and terms stated in the appointing order, and the court may set a new basis and new terms after giving the parties notice and an opportunity to be heard. The court shall allocate payment of the special master’s compensation among the parties in an amount and a manner that the court deems equitable. The court may waive a party’s obligations to pay the special master’s compensation upon a showing of good cause.

(c) The court may request the State Water Resources Control Board or the department to recommend candidates for appointment as a special master or to review the qualifications of candidates.

(d) (1) In any adjudication in a basin in which one or more groundwater sustainability agencies have adopted a groundwater sustainability plan that has been approved by the Department of Water Resources, the court shall request that the groundwater sustainability agency provide a technical report, if the agency is able to do so at a reasonable effort and expense. The report shall, at a minimum, quantify and describe the groundwater use of parties that have not otherwise appeared before the court. The groundwater sustainability agency may include in the report, but is not limited to, parties excused or treated separately pursuant to subdivision (d) of Section 833, parties for which the court lacks jurisdiction, and parties that have been, or it is anticipated may be, found in default by the court. The groundwater sustainability agency may provide the report at its own election, and may include areas outside of its jurisdictional boundary if another groundwater sustainability agency in the basin is unable or unwilling to provide a report.

(2) A groundwater sustainability agency that provides a report pursuant to paragraph (1) shall not be entitled to a fee for its services, but shall be paid or reimbursed the total expense incurred by the agency, including salaries, wages, traveling expenses, and all costs of whatsoever character are properly chargeable to providing the report. The court shall apportion the total expenses reimbursable to the groundwater sustainability agency for providing the report among the parties in an amount, and in a manner, that the court deems equitable.

(3) During the pendency of the report provided pursuant to paragraph (1), upon a noticed motion by a groundwater sustainability agency, and following a hearing by the court after at least 10 days’ notice to the parties, the court may order such interim or partial payments of the expense to be made by the parties.

(4) A report provided by a groundwater sustainability agency pursuant to paragraph (1) shall be prima facie evidence of the physical facts found in the report, but the court shall hear evidence that may be offered by any party to rebut the report or the prima facie evidence.

(e) This section does not limit the authority of the court to make a reference pursuant to Chapter 1 (commencing with Section 2000) of Part 3 of Division 2 of the Water Code.

(f) This section does not limit the authority to appoint a watermaster pursuant to Chapter 3 (commencing with Section 4050) of Part 4 of Division 2 of the Water Code or any other law.