AB 1894 California Assembly · 2025-2026 Regular Session

Fish and wildlife: invasive mussels: imported water.

Summary

Existing law, until January 1, 2030, generally prohibits a person from possessing, importing, shipping, or transporting in the state, or from placing, planting, or causing to be placed or planted in any water within the state, invasive mussels, and authorizes the Director of Fish and Wildlife, or the director's designee, to engage in various enforcement activities with regard to invasive mussels. Existing law, until January 1, 2030, requires a public or private agency that operates a water supply system to cooperate with the Department of Fish and Wildlife to implement measures to avoid infestation by invasive mussels and to control or eradicate any infestation that occurs in a water supply system. Existing law requires any person, or federal, state, or local agency, district, or authority that owns or manages a reservoir, where specified activities are permitted, except as specified, to develop and implement a program designed to prevent the introduction of invasive mussel species, as provided. Existing law requires any entity that discovers invasive mussels within the state to immediately report the discovery to the department. This bill would prohibit a public agency from prohibiting imported water deliveries for groundwater replenishment, as defined, due to invasive mussels if the importation complies with a specified invasive mussel control plan and unless there is substantial, documented evidence of a proven health and safety risk as a result of the invasive mussels. The bill would include findings that changes proposed by this bill address a matter of statewide concern rather than a municipal affair and, therefore, apply to all cities and counties, including charter cities and charter counties.

Issues: ✓ Environment

Bill status passed both 4 of 5 stages cleared

Introduction

Feb 2026

Committee Review

Jun 2026

Assembly Passage

May 2026

Senate Passage

Aug 2026

Governor

Introduced Feb 12, 2026 Last action Aug 27, 2026

Maddy AI version diff · 5 comparisons

What changed between versions

08/24/26 - Enrolled → AB1894 · 1 edit

MINOR

No substantive legislative changes were made between these two versions. The diff reflects a transition from the formal enrolled document format (with governor's signature block, clerk certifications, and page numbers) to a web page rendering of the same bill text. The actual statutory language adding Section 2302.5 to the Fish and Game Code is identical in both versions.

TECHNICAL

The document was reformatted from an official enrolled bill layout (with signature blocks, page numbers, and legislative counsel formatting) into a web page presentation with navigation elements, search tools, and status information. No changes to the underlying statutory text.

04/16/26 - Amended Assembly → 05/28/26 - Amended Senate · 3 edits · May 28, 2026

MINOR

The Senate amendment removed the bill's broad preemption provision that would have given the state exclusive authority to regulate invasive mussels and barred local agencies from adopting any related ordinances or policies. In its place, the Senate added a new condition requiring that imported water deliveries for groundwater replenishment comply with a state-approved invasive mussel control plan before they are protected from prohibition by public agencies. The bill shifted from a sweeping preemption approach to a narrower, compliance-based protection for water deliveries.

Scope change

The bill's scope narrowed significantly. The Assembly version broadly preempted all local regulation of invasive mussels statewide. The Senate version drops that preemption entirely and instead focuses narrowly on protecting imported water deliveries for groundwater replenishment, but only when those deliveries comply with a state-approved control plan. Local agencies retain their general authority to regulate invasive mussels unless specifically addressed by this narrower provision.

SCOPE

Removed the provision granting the state exclusive authority to regulate invasive mussels and prohibiting cities, counties, districts, or other local agencies from adopting, enforcing, or implementing any ordinance, rule, regulation, policy, or other declaratory action pertaining to invasive mussels unless expressly authorized by state law. Also removed the clause stating that conflicting local ordinances are preempted and have no force or effect.

Removed the savings clause that stated the section does not preclude local agencies from cooperating with or implementing measures required by the department or other state agencies pursuant to state-approved invasive mussel prevention or control programs.

REQUIREMENT

Added a new condition that imported water deliveries for groundwater replenishment must be made in compliance with an invasive mussel control plan approved by the Department of Fish and Wildlife pursuant to subdivision (d) of Section 2301 in order to be protected from prohibition by a public agency due to invasive mussels.

02/12/26 - Introduced → 03/16/26 - Amended Assembly · 6 edits · Mar 16, 2026

MODERATE

AB 1894 was substantially expanded from a minor nonsubstantive cleanup of the existing ban on Caulerpa algae to a bill that also adds state preemption over local regulation of invasive mussels (quagga, zebra, and golden mussels). The amended bill establishes that the state has exclusive authority to regulate invasive mussels and prohibits local agencies from adopting their own rules on the subject unless expressly authorized by state law. This matters because it prevents a patchwork of local mussel regulations across California's many cities and counties.

Scope change

The bill's scope expanded dramatically from a minor technical cleanup of the existing Caulerpa algae prohibition to a comprehensive state preemption regime over invasive mussel regulation, effectively removing local government authority to set their own rules on quagga, zebra, and golden mussels statewide.

SCOPE

New Section 2302.5 added to the Fish and Game Code establishing that the state has exclusive authority to regulate invasive mussels, including quagga mussels (Dreissena rostriformis bugensis), zebra mussels (Dreissena polymorpha), and golden mussels (Limnoperna fortunei).

A new Section 2 declares that the preemption provision addresses a matter of statewide concern rather than a municipal affair under Section 5 of Article XI of the California Constitution, meaning it applies to all cities and counties including charter cities and charter counties.

ENFORCEMENT

Local agencies (cities, counties, districts, or other local agencies) are prohibited from adopting, enforcing, or implementing any ordinance, rule, regulation, policy, or other declaratory action pertaining to invasive mussels unless expressly authorized by state law. Conflicting local ordinances are preempted and have no force or effect.

ELIGIBILITY

An exception is included allowing local agencies to cooperate with or implement measures required by the Department of Fish and Wildlife or other state agencies pursuant to state-approved invasive mussel prevention or control programs.

TECHNICAL

The original Section 2300 (Caulerpa algae ban) changes remain nonsubstantive: fixing grammatical errors such as 'No A person shall not' to 'A person shall not' and 'authorization by of' to 'authorization of.'

FISCAL

Fiscal committee review changed from 'no' to 'yes,' indicating the amended bill now requires fiscal committee approval due to its expanded scope.

Floor votes · Senate Aug 17, 2026 · Assembly May 4, 2026

How they voted

40–0

Passed

Total votes 40

Aug 17, 2026

D Democratic30

30 Yea

100% Yea

R Republican10

10 Yea

100% Yea

Vote distribution

All Yea All Nay Mixed No data

Full legislative history

Actions timeline

Total actions

Key actions

Committee

Amendments

Aug 20, 2026

Lower · Passed

Senate amendments concurred in. To Engrossing and Enrolling. (Ayes 77. Noes 0.).

lower

Aug 17, 2026

Introduced

In Assembly. Concurrence in Senate amendments pending.

lower

Aug 17, 2026

Upper · Passed

Read third time. Passed. Ordered to the Assembly. (Ayes 39. Noes 0.).

upper

Jun 22, 2026

Upper · Passed

From committee: Be ordered to second reading pursuant to Senate Rule 28.8.

upper

Jun 9, 2026

Upper · Passed

From committee: Do pass and re-refer to Com. on APPR. (Ayes 7. Noes 0.) (June 9). Re-referred to Com. on APPR.

upper

May 28, 2026

Introduced

From committee chair, with author's amendments: Amend, and re-refer to committee. Read second time, amended, and re-referred to Com. on N.R. & W.

upper

May 13, 2026

Committee

Referred to Com. on N.R. & W.

upper

May 4, 2026

Lower · Passed

Read third time. Passed. Ordered to the Senate. (Ayes 74. Noes 0. Page 4914.)

lower

Apr 29, 2026

Lower · Passed

From committee: Do pass. (Ayes 14. Noes 0.) (April 29).

lower

Apr 20, 2026

Committee

Re-referred to Com. on APPR.

lower

Apr 16, 2026

Lower · Passed

Read second time and amended.

lower

Apr 15, 2026

Introduced

From committee: Amend, and do pass as amended and re-refer to Com. on APPR. (Ayes 13. Noes 0.) (April 14).

lower

Mar 17, 2026

Committee

Re-referred to Com. on W., P., & W.

lower

Mar 16, 2026

Introduced

From committee chair, with author's amendments: Amend, and re-refer to Com. on W., P., & W. Read second time and amended.

lower

Mar 16, 2026

Committee

Referred to Com. on W., P., & W.

lower

Feb 13, 2026

Lower · Passed

From printer. May be heard in committee March 15.

lower

1 primary · 0 co-sponsors