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Water Rights/Case Library

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Casitas Municipal Water District v. United States, 543 F.3d 1276 (Fed. Cir. 2008)

Why this matters: When the government cuts your water to save a fish, is that a taking it has to pay for? The courts have been unable to give a stable answer for 25 years. Casitas won the theory and then lost the case. That gap is the most honest summary of water takings law available.

Doctrine: Takings, water rights, Endangered Species Act

Case name and citation

Casitas Municipal Water District v. United States, 543 F.3d 1276 (Fed. Cir. 2008) (Casitas III), later proceedings, 102 Fed. Cl. 443 (2011), aff’d, 708 F.3d 1340 (Fed. Cir. 2013). Compare Tulare Lake Basin Water Storage District v. United States, 49 Fed. Cl. 313 (2001).

Court and year

United States Court of Appeals for the Federal Circuit. Decided September 25, 2008. Follow-on decision decided February 27, 2013.

One-line holding

Requiring a water district to divert its water down a fish ladder for endangered species protection is analyzed as a physical taking rather than a regulatory takingregulatory takingWhen a government rule restricts your property so severely that courts treat it as taking the property, which would require payment. Wisconsin courts have been unusually willing to say a shoreline rule is not one., but the claim does not accrue until the diversiondiversionMoving water out of the Great Lakes basin. The Compact bans new ones except in a few narrow cases. actually interferes with the district’s right to beneficial usebeneficial useActually using water for something productive: farming, drinking, industry, and in most western states now, keeping fish alive. In the West it is what earns you a water right and what caps how much you get..

Facts

Casitas Municipal Water District operates the Ventura River Project in southern California under a contract with the Bureau of Reclamation and a state water license. Its license limits it to 28,500 acre-feetacre-footEnough water to cover 1 acre a foot deep: 325,851 gallons. Roughly what 2 or 3 suburban households use in a year. per year, and by its terms limits the right to water “actually beneficially used.”

In 1997 the West Coast steelhead was listed as endangered. A biological opinion required Casitas to build and operate a fish ladder, which meant sending a portion of its water down the ladder rather than into storage.

Casitas sued for breach of contract and for a Fifth Amendment taking.

The trial court held the regulatory takingsregulatory takingWhen a government rule restricts your property so severely that courts treat it as taking the property, which would require payment. Wisconsin courts have been unusually willing to say a shoreline rule is not one. standard applied. It reached that conclusion despite a prior decision by the same judge in Tulare Lake Basin (2001), which had found that depriving plaintiffs of water they were otherwise entitled to was a physical taking. The court concluded that the Supreme Court’s intervening decision in Tahoe-Sierra Preservation Council v. Tahoe Regional Planning Agency (2002) required a different result.

Casitas conceded it could not win under the regulatory takings framework of Penn Central Transportation Co. v. New York City, so the trial court dismissed and entered judgment for the United States. Casitas appealed.

When the federal government requires a water rights holder to divert water for endangered species compliance, is that a physical taking subject to per se rules, or a regulatory taking subject to Penn Central balancing?

Holding and reasoning

The Federal Circuit reversed on the takings framework. Physical, not regulatory.

Its reasoning was categorical. A physical taking is “the paradigmatic taking” and occurs through direct government appropriation or physical invasion. By directing Casitas to divert water down the fish ladder, the government appropriated Casitas’s water for its own use.

The size of the appropriation does not matter under per se rules. Take a tiny slice and it is still a taking requiring just compensation.

On the contract claims, the court affirmed. Reclamation breached the contract when it required Casitas to allocate part of its contractual water to the fish ladder, and the sovereign acts doctrine did not shield the government because it could have performed without violating the Endangered Species Act.

Then Casitas lost anyway. On remand, the Court of Federal Claims asked whether California law recognizes a right to divert independent of a right to beneficial usebeneficial useActually using water for something productive: farming, drinking, industry, and in most western states now, keeping fish alive. In the West it is what earns you a water right and what caps how much you get.. It answered no. “The only compensable right under California water law is a right to beneficial use,” and a holder of an appropriativeprior appropriationThe western US rule. Whoever first took water and put it to use has the strongest claim, no matter where their land sits. The shorthand is "first in time, first in right." right “possesses no legal entitlement to water that is diverted but never beneficially used.”

So Casitas had to show interference with beneficial use, meaning that customers actually received less water because of the biological opinion operating criteria. Casitas argued it lost 3,942 acre-feetacre-footEnough water to cover 1 acre a foot deep: 325,851 gallons. Roughly what 2 or 3 suburban households use in a year. per year, and could not show that water would otherwise have reached customers.

The claim was dismissed as unripe, without prejudice. The Federal Circuit affirmed in 2013, holding that a physical takings claim accrues only when the physical act constituting the taking occurs, so the statute of limitations has not started running. Casitas can come back if and when deliveries drop.

Why it matters

This case is in the library specifically to illustrate that the law here is unsettled, and to be honest about it rather than pretend otherwise.

Tulare Lake Basin (2001) held that curtailing water deliveries under the Endangered Species Act was a physical taking, and awarded compensation. That decision was criticized for not analyzing whether plaintiffs held a vested property right in the water at all, and the same judge later concluded he had wrongly focused on the finality of the loss rather than the character of the government’s action.

Casitas restored the physical takings framework at the Federal Circuit, which is favorable to water users in principle. Then the beneficial use limitation gutted it in practice.

The doctrinal uncertainty is genuine and unresolved. Three questions drive outcomes and none has a clean answer:

  • Is the property interest the right to divert, or only the right to beneficial use? California says beneficial use. Other states define appropriativeprior appropriationThe western US rule. Whoever first took water and put it to use has the strongest claim, no matter where their land sits. The shorthand is "first in time, first in right." rights differently.
  • Is curtailment a physical appropriation or a regulation of use? Casitas says physical. Reasonable judges have said otherwise.
  • When does the claim accrue? Casitas says when beneficial use is actually impaired, which can be years after the restriction begins.

The practical result is that water users facing environmental curtailment have a theory that sounds strong and a record of rarely collecting.

The state law dependency is the deepest point. Federal takings analysis begins by asking what property you have, and that question is answered by state law. So the same federal restriction can be a taking in one state and nothing in another. Compare Edwards AquiferaquiferUnderground rock or sand with water in the spaces between the grains. It is not an underground lake. Water seeps through it slowly, often only feet per year. Authority v. Day (2012), where Texas defined the property interest expansively and opened the door to compensation. See 2012-edwards-aquifer-authority-v-day.md.

What it means for a landowner today

Little direct application in Wisconsin. Wisconsin riparian rightsriparianThe eastern US rule, and Wisconsin's rule. If your land touches a lake or stream, you get reasonable use of that water, shared with everyone else whose land touches it. The rights come with the land and generally cannot be sold separately from it. and well permits are not the kind of quantified, contract-based federal project water at issue here.

The transferable principles matter more:

  • Your compensable property interest is defined by state law, and it is usually narrower than you assume. In Wisconsin, riparian rightsriparianThe eastern US rule, and Wisconsin's rule. If your land touches a lake or stream, you get reasonable use of that water, shared with everyone else whose land touches it. The rights come with the land and generally cannot be sold separately from it. are usufructuary rightsusufructuary rightsIn treaty law, the reserved right to hunt, fish, and gather on land that was ceded. Wisconsin Ojibwe bands hold these under the 1837 and 1842 treaties. of reasonable usereasonable useYou can use the water however you like until it unreasonably harms someone else's use. This is Wisconsin's groundwater rule. The catch: it is enforced by a lawsuit after the harm, not by a permit beforehand., not ownership of water.
  • Regulation that reduces your water use is unlikely to be compensable in Wisconsin. Just v. Marinette County points strongly the other way for land use, and the public trust doctrinepublic trust doctrineThe state holds navigable waters and the land beneath them for everyone, and cannot sign that away. Wisconsin's version is written into the state constitution and is among the strongest in the country. supplies a background principle limiting what was ever yours. See 1972-just-v-marinette-county.md.
  • Do not buy land on the assumption that if regulation later restricts water use, you’ll be paid. That bet has a poor track record even in states friendlier to it.

What to verify: whether any endangered or threatened species, critical habitat, or impaired water designation applies to or near the parcel, and whether any existing approval could be conditioned as a result. Who verifies: the Wisconsin DNR, the U.S. Fish and Wildlife Service for federally listed species, and a Wisconsin real estate attorney.

Subsequent history / is it still good law

The 2008 physical takings holding remains Federal Circuit law as of July 2026 and has not been overruled.

The 2013 decision (708 F.3d 1340) is the practical last word on this dispute. Casitas’s claim was dismissed without prejudice as unripe. It may be refiled if operating criteria actually reduce deliveries to customers.

Tulare Lake Basin is widely regarded as poorly reasoned and has been effectively superseded by Casitas within the Federal Circuit, though it has never been formally overruled by an appellate court.

The Supreme Court has not resolved whether water curtailment is a physical or regulatory taking. Until it does, expect continued inconsistency across circuits and state courts.

Sources

Research demo, not legal advice. Facts current as of July 2026. Water law is state-specific and moves quickly, so confirm anything you plan to act on with a licensed attorney and the relevant state agency.