Dams: exceptions.

Assembly Member Soria’s measure would carve a narrow exemption from the definition of dam for nine named weirs that meet a set of criteria, creating a targeted shift in how these agricultural water delivery structures are regulated. The bill would exempt a barrier from dam status if it does not impound water above the top of a levee and the maximum storage behind the barrier has at least three feet of freeboard, provided the structure functions as a weir. The nine weirs identified by name in the measure would qualify if they meet these conditions and are considered weirs under the bill’s definitions.

Under the amended framework, existing exemptions for small barriers—such as those not exceeding six feet in height or with storage not in excess of 15 acre-feet—continue to apply to other structures; the new provision targets only the nine named weirs: Peoples Weir, Reynolds Weir, Last Chance Weir, Lemoore Diversion Weir, Island Weir, Crescent Weir, Stinson Weir, Empire Weir No. 1, and Empire Weir No. 2. The bill also defines “weir” in relation to agricultural water delivery and removable components that regulate flow and that are part of a federal flood-control system, establishing the basis for applying the exemption to these structures.

The measure would shift regulatory oversight for these nine weirs away from dam-safety oversight under the state framework to the extent that such oversight is tied to the dam definition. Federal flood-control authorities or local entities with jurisdiction over these structures would likely continue to regulate them under their respective authorities, though the bill does not specify new state permitting or enforcement mechanisms. The fiscal provisions indicate no new appropriations, and the bill is to be considered by a fiscal committee, with the overall effect focused on definitional scope rather than new funding or programs. The bill does not specify an explicit operative date within the text.

Legislative history shows introduction in February 2025, amendments in March and June, and passage in the Senate and Assembly in early September 2025, followed by enrollment on September 8, 2025. The proposal narrows the scope of state dam-safety regulation by creating a limited exemption for the nine named weirs, while keeping other existing exemptions for small barriers intact. The ultimate implementation and any practical coordination with federal authorities or local operators will depend on how agencies recognize the nine structures as non-dams for purposes of the state framework and how they continue to be regulated under federal flood-control regimes.