(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.
§ 833.Applicability to Actions Determining Rights to Extract Groundwater In a Basin
Title 10. Actions In Particular Cases · Chapter 7. Actions Relating to Groundwater Rights · Article 2. Scope of Action · Last amended 2026 · Last verified July 28, 2026
In one sentenceSection 833 applies this chapter to actions that would comprehensively determine groundwater rights in a basin, while excluding narrower interference disputes, limited-party actions, certain already-adjudicated areas, and letting the court join related surface water claims or exempt minor water users.
Full Text of § 833
(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.
Plain-English Summary
Not every groundwater lawsuit is a comprehensive adjudication, and this section draws the line. Subdivision (a) applies the chapter broadly to actions that would comprehensively determine rights to extract groundwater in a basin, whatever the legal basis of those rights. Subdivision (b) then carves out four categories that fall outside the chapter: actions limited to interference between specific extraction facilities, actions limited to a specific source of recharge, actions resolvable among a limited number of parties without a comprehensive determination, and certain areas already adjudicated before this chapter's enactment (unless a court handling an expansion of that adjudicated area orders otherwise).
Subdivision (c) lets the court require joinder of people claiming rights to an interconnected surface water body or subterranean stream, when including them is necessary for a fair and effective determination of the basin's groundwater rights — recognizing that groundwater and connected surface water don't always respect a strict legal boundary.
Subdivision (d) addresses the other end of the spectrum: small users. If claims to extract or divert no more than five acre-feet of water per year wouldn't materially affect other parties' rights, the court may exempt those claimants (though they can elect to stay in the case) or handle them separately to reduce their burden while still resolving their claims. That flexibility recurs in § 840's case management provisions and § 850's judgment criteria, both of which account for parties exempted or treated separately under this section.
Frequently Asked Questions
Does every lawsuit about groundwater rights count as a "comprehensive adjudication"?
No. Section 833(b) excludes actions limited to interference between specific facilities, disputes over a specific recharge source, actions resolvable among a limited number of parties, and certain already-adjudicated areas.
Can surface water rights get pulled into a groundwater adjudication?
Yes. If the court finds it necessary for a fair and effective determination, it may require joinder of people claiming rights to an interconnected surface water body or subterranean stream.
What happens to small water users in a comprehensive adjudication?
If their claims don't exceed five acre-feet per year and wouldn't materially affect other parties' rights, the court may exempt them or process their claims separately to ease their burden.
Can an exempted small user still participate in the case?
Yes. Section 833(d)(1) lets an exempted claimant elect to continue as a party despite the exemption.
Amendment History
Amended by Stats 2025 ch 643 (AB 1466),s 1, eff. 1/1/2026. Added by Stats 2015 ch 672 (AB 1390),s 1, eff. 1/1/2016.
Source & verification. Section text is reproduced verbatim from
the Deering's California Codes Annotated / vLex. Enacted by the California Legislature.
Last verified July 28, 2026.
· Official source
Also known as: comprehensive groundwater adjudication scope californiaexempt small groundwater user california