Lead Opinion
Is a public entity liable in tort or inverse condemnation for damage to downstream riparian property caused by the discharge of surface waters into a natural watercourse abutting its property? The Court of Appeal held that there could be no liability.
We granted the petition of plaintiffs, owners of damaged properties, to consider whether the “natural watercourse rule” stated in Archer v. City of Los Angeles (1941)
We conclude that Archer does not correctly state the principles presently applicable to the liability of riparian landowners. To the extent that Archer also held that article I, section 19 of the California Constitution did not create liability, it has been overruled by subsequent decisions of this court.
When alterations or improvements on upstream property discharge an increased volume of surface water into a natural watercourse, and the increased volume and/or velocity of the stream waters or the method of discharge into the watercourse causes downstream property damage, a public entity, as a property owner, may be liable for that damage. The test is whether, under all the circumstances, the upper landowner’s conduct was reasonable. This rule of reasonableness applies to both private and public landowners, but it requires reasonable conduct on the part of downstream owners as well. This test requires consideration of the purpose for which the improvements were undertaken, the amount of surface water runoff added to the streamflow by the defendant’s improvements in relation to that from development of other parts of the watershed, and the cost of mitigating measures available to both upper and downstream owners. Those costs must be balanced against the magnitude of the potential for downstream damage. If both plaintiff and defendant have acted reasonably, the natural watercourse rule imposes the burden of stream-caused damage on the downstream property.
We also conclude that a governmental entity may be liable under the principles of inverse condemnation for downstream damage caused by an
Finally, because the development of any property in the watershed of a natural watercourse may add additional runoff to the stream, all of which may contribute to downstream damage, it would be unjust to impose liability on an owner for the damage attributable in part to runoff from property owned by others. Therefore, an owner who is found to have acted unreasonably, and to have thereby caused damage to downstream property, is liable only for the proportion of the damage attributable to his conduct.
Although we conclude that the Court of Appeal erred in holding that the natural watercourse rule insulated defendants from both tort and inverse condemnation liability, we shall affirm the judgment. After a review of the record we are satisfied that the court properly held that Reliez Creek, the watercourse which is the focus of this litigation, had not itself become a public improvement at the time the damage of which plaintiffs complain occurred and that no public improvements in the creekbed contributed to the damage suffered by plaintiffs. That review also satisfies us that the evidence does not support a conclusion that the damage to any plaintiff’s property was the result of unreasonable conduct by any defendant in the manner in which it discharged surface water runoff into Reliez Creek, or establish that there was damage to plaintiffs’ properties that could not have been prevented had they undertaken reasonable measures to protect their properties.
I
Underlying Facts
Plaintiffs are the owners of property abutting Reliez Creek in Contra Costa County. The ownership interest of each plaintiff extends to the center
Plaintiffs purchased their respective properties at various times between 1965 and 1978. Many inspected the creek bank at the time they purchased their property. None observed any erosion. Although some erosion of the creek banks occurred subsequently, damage to the creek banks during the winter of 1981-1982, a period of unusually heavy rainfall, was more significant. There was evidence that the increased flow of waters led to failure of the creek banks adjacent to plaintiffs’ properties, widening the creek in some locations from a width of 40 feet to a width of 110 feet. There was also evidence that the city and county were aware that the increased flow of surface waters caused by development was causing and would cause damage to the creek banks. The damage to the creekside property might have been prevented by check dams and dikes, upstream diversion structures, and retention basins. That evidence did not relate the need for such structures to the increased runoff from defendants’ properties or demonstrate that it would be reasonable to impose the cost of such structures on the named defendants, whose property comprised a small percentage of the watershed.
In 1983, plaintiffs filed this action to recover for “extensive landslide” damage to their properties adjacent to the Reliez Creek, damage allegedly
Named as defendants were the City of Lafayette (City), the County of Contra Costa (County), the Contra Costa County Flood Control District (District), the California Department of Transportation (CalTrans), the Bay Area Rapid Transit District (BART), and private parties whose involvement is not in issue here.
CalTrans and County were allеged to be developers, designers, builders, owners, and maintained of Highway 24, Old Tunnel Road, and Pleasant Hill Road. BART was sued as the owner and developer of the rapid transit right-of-way through County. All defendants allegedly created and maintained a storm drainage system which included those portions of Reliez Creek that adjoined plaintiffs’ real property.
Plaintiffs’ inverse condemnation cause of action, brought under the authority of article I, section 19 of the California Constitution,
Trial of the liability and damages issues was bifurcated. At the close of plaintiffs’ case-in-chief on liability, the trial court granted defendants’ motions for judgment on the inverse condemnation cause of action (Code Civ. Proc., § 631.8) and nonsuit on thе tort causes of action (Code Civ. Proc., § 581c), except insofar as plaintiffs claimed City’s liability arose from the maintenance of two structures, the Sizeler outfall and the sheet pile structure within Reliez Creek. Judgment for City was then granted at the close of defendants’ evidence when the trial court found that plaintiffs had not proved that either structure was a substantial concurring cause of the damage to any plaintiff’s property.
In granting defendants’ motions the trial court ruled: (1) there was insufficient evidence to establish that Reliez Creek was a storm drainage public improvement;
II
Plaintiffs’ Appeal
Plaintiffs’ appeal was directed principally to the disposition of their inverse condemnation claim. They argued, however, that the trial court erred in applying the Archer natural watercourse rule to give defendants absolute immunity from liability on both the inverse condemnation and the tort claims. With respect to the inverse condemnation claims, plaintiffs also argued that they were entitled to relief under Belair v. Riverside County Flood Control Dist. (1988)
The Court of Appeal affirmed the judgment of the trial court in all respects, holding that it was bound by Auto Equity Sales, Inc. v. Superior Court (1962)
Ill
The Archer Decision
The Court of Appeal based its ruling on this court’s statement in Archer that “there is no diversion [for which liability would exist] if surface waters, flowing in no defined channel, are for a reasonable purpose gathered together and discharged into the stream that is their natural means of drainage even though the stream channel is inadequate to accommodate the increased flow.” (Archer, supra,
The Court of Appeal also concluded that decisions subsequent to Archer had reaffirmed, not repudiated, the holding in Archer that governmental entities are immune from liability under article I, section 19 of the California Constitution insofar as that holding was applicable to damages for which a private owner would be shielded from liability by the natural watercourse rule. That “Archer exception” to inverse condemnation liability held that “[i]f the property owner would have no cause of action were a private person to inflict the damage, he can have no claim for compensation from the state.” (Archer, supra,
To put in perspective our examination of public and private landowner responsibility for damage to downstream property caused by discharge of “surface waters” into a “natural watercourse,” it is therefore appropriate to define these terms and to describe in more detail the Archer decision.
A. Surface Waters.
, In the arcane area of water law under consideration in this case, the rights and liabilities of private property owners for property damage or
B. Natural Watercourse.
A natural watercourse “is a channel with defined bed and banks made аnd habitually used by water passing down as a collected body or stream in those seasons of the year and at those times when the streams in the region are accustomed to flow. It is wholly different from a swale, hollow, or depression through which may pass surface waters in time of storm not collected into a defined stream.” (San Gabriel V.C. Club v. Los Angeles (1920)
C. Archer.
Archer, supra,
The plaintiffs in Archer were owners of property near La Ballona Lagoon. La Ballona Creek, a natural watercourse, drained surface waters from an area of about 134 square miles into the lagoon, from which the waters emptied into the Pacific Ocean. As residential and commercial development occurred in the hills at the upper reaches of the creek, surface waters that had not followed a defined course were diverted into ditches and channels which emptied into the creek. Defendants, the City of Los Angeles and the Los Angeles County Flood Control District, straightened, widened and deepened the creek. They constructed concrete stоrm drains to improve drainage. As a result of these changes less water was absorbed into the ground and the flow of waters from the creek into the lagoon was accelerated. Defendants did not improve the outlet from the lagoon to the ocean, however, and after a heavy rain the water in the lagoon backed up, flooding plaintiffs’ property. They sued on a theory of inverse condemnation under former section 14 (now section 19) of article I of the California Constitution. Nonsuit was granted and plaintiffs appealed.
Under what was then this court’s view of article I, section 14, the predecessor to present section 19, the Constitution did not create a cause of action. It did no more than waive the state’s sovereign immunity if a cause of action would otherwise exist. Therefore, plaintiffs could recover only if a private landowner would be responsible for the damage suffered by plaintiffs. If a private party had the right to inflict the damage without incurring liability, the governmental defendants would not be liable. The court therefore analyzed the claim as it would one involving the rights of private landowners to drain surface waters from their property into a natural watercourse.
The court stated the applicable rules as:
1. A lower owner may not recover for injury to his land caused by improvements made in the stream for the purpose of draining or protecting the land above, even though the channel is inadequate to accommodate the increased flow of water resulting from the improvements. It is immaterial that the improvements increase the volume and velocity of the water, that the lower owner’s burden of protecting his property is increased, or that his land is damaged.
2. Improvements must follow the natural drainage and may not divert water into a different channel, but straightening, widening, and deepening the channel does not constitute a diversion.
*347 3. There is no diversion if, for a reasonable purpose, diffused surface waters are gathered and discharged into a stream that is their natural means of drainage even if the watercourse is inadequate to accommodate the increased flow. An upper riparian landowner may gather surface waters for a reasonable purpose and discharge them into a natural watercourse without liability to a lower owner for damage caused by the increased flow.
Possibly because there was no claim that the defendants had acted unreasonably in their upstream improvements, however, the Archer holding omitted reference to an important qualification on the rights of the upper riparian owner implied in San Gabriel V.C. Club v. Los Angeles, supra,
This qualification was implied repeatedly in San Gabriel V.C. Club v. Los Angeles, supra,
Certainly the San Gabriel V.C. Club decision did not hold that any surface water drainage into a natural watercourse was immunized in this state. It implied the contrary, and made it clear that this question was not before the court. “[Decisions in other states go further than it is necessary to go in this case, and hold that a riparian owner has no right to complain because the volume of water in the stream is increased by artificially draining surface waters into it above, provided only the stream is the natural drainage channel for the lands so drained.” (182 Cal. at pp. 401-402.)
Since there was no issue involving unreasonable conduct in draining surface waters into the stream bed in Archer, supra,
Moreover, the principal focus of both Archer, supra,
IV
Rights and Liabilities of Private Property Owners
Defendants are both property owners and governmental entities. Their potential liability as governmental entities for damage caused by discharge of surface waters into a natural watercourse is no longer limited, as it was at the time of Archer, supra,
A. The California Civil Law Rule.
At common law the “common enemy doctrine” gave an owner of land over which surface water flowed from a higher elevation the right to obstruct the flow of that water, turning it back or diverting it onto the land of another owner, without liability for any damage that might result. (Keys v. Romley, supra,
By contrast, the civil law rule adopted for California more than a century ago (see Ogburn v. Connor (1873)
B. The Natural Watercourse Rule..
The rule differed with respect to discharge of surface waters into a natural watercourse. As we noted in Archer (supra,
Thus, a riparian owner might be the ultimate “beneficiary” of the civil law rule subjecting lower parcels of property to the burden of surface water runoff from parcels at a higher elevation. The owner had the right, in turn, however, to discharge the surface waters into a natural watercourse without liability for damage that the addition of these waters to the stream might do to downstream riparian property. The downstream riparian owner is also deemed to take the property subject to an easement or servitude, one burdening the downstream property with accepting the flow of whatever water is thereby carried onto or through it in a natural watercourse.
“[A] riparian owner has no right to complain because the volume of water in the stream is increased by artificially draining surface waters into it above, provided only the stream is the natural drainage channel for the lands so drained. Furthermore, this rule is adopted regardless of whether the so-called common-law rule concerning surface waters prevails in the particular jurisdiction or, as here, the civil-law rule, which forbids the gathering together of surface waters and discharging them as a stream upon adjoining lands. If the surface waters are gathered and discharged into the stream which is their natural means of drainage, so that they come to the land below only as a part of the stream, it is held that no action lies because of their being added.” (San Gabriel V.C. Club v. Los Angeles, supra,
The immunity of the upper riparian owner for downstream damage caused by his discharge of surface water runoff into a natural watercourse through improvements was initially for improvements undertaken to drain and/or protect the upper riparian owner’s land. “[A]n improvement for the purposes of the drainage and protection of lands above does not give a lower riparian owner on the stream a cause of action merely because such improvement increases the volume of water in the stream as it comes to his land, even though the burden he is necessarily under of protecting his land against the stream is thereby increased and his land is injured because of his failure to meet such increased burden; and, further ... the rule is not subject to the limitation that the increased volume must not be such as to make the stream exceed the capacity of its channel.” (San Gabriel V.C. Club v. Los Angeles, supra,
We again recognized that this immunity was for damage to downstream land caused by improvements made in the stream for the purpose of draining or protecting the land above in Archer. (Supra,
The California rules applicable to runoff of surface waters onto adjacent property and into natural watercourses have accommodated progression from a rural, agricultural society to gradual urbanization. Although immunity of upper landowners was limited to “natural” runoff of surface waters, it was broad enough to encompass surface water runoff from fields cultivated in a natural way, even though cultivation altered the runoff from that which occurred from unfilled fields. (Coombs v. Reynolds (1919)
As suggested above, the natural watercourse rule has two aspects. The first permits the riparian landowner to gather surface waters and discharge them into the watercourse at a location other than that at which natural drainage would occur. The second permits the owner to make improvements in the bed of the stream to improve drainage and to protect the land from erosion by constructing dikes or embankments even though the result mаy be increased flow and velocity which might damage the property of lower riparian owners. Both aspects of the rule have as their purpose facilitating the development of upstream properties..“Not to permit an upper land owner to protect his land against the stream would be in many instances to destroy the possibility of making the land available for improvement or settlement and condemn it to sterility and vacancy.” (San Gabriel V.C. Club v. Los Angeles, supra,
C. The Contemporary Rule of Reasonableness.
The modern rule governing landowner liability for surface water runoff and drainage is no longer simply a rule of property law dependent upon the existence of rights, servitudes, or easements. The civil law rule was modified more than a quarter of a century ago by the landmark decision in Keys v. Romley, supra,
“If the actions of both the upper and lower landowners are reasonable, necessary, and generally in accord with the foregoing, then the injury must necessarily be borne by the upper landowner who changes a natural system of drainage, in accordance with our traditional civil law rule.” (Keys v. Romley, supra,
At least with respect to surface water runoff onto adjacent lands, the California rule is that stated in Keys v. Romley, supra,
It has been suggested that with the adoption of the reasonable use test for surface waters “there is no longer any valid reason for distinguishing between surfaсe waters and those that flow through a natural watercourse with respect to the rights and obligations of the respective property owners.” (5 Miller & Starr, Cal. Real Estate (2d ed. 1989) § 14:24, p. 357; see also Hall v. Wood (Miss. 1983)
Defendants argue that the natural watercourse rule does not include a reasonableness element and should remain the law. They contend that the rationale on which the rule is based remains valid, and that application of the Keys v. Romley rule of reasonableness would create a virtual strict liability for public entities owning streets, storm drains, or other water-impervious improvements. Public entities, they claim, would bear extraordinary liability solely because storm waters falling on their thoroughfares ultimately reach a natural watercourse. The natural watercourse rule, they argue, properly permits the natural and intended usage of the creeks and waterways as a means of discharging the waters which would normally be conveyed therein.
The argument both misstates the issue and exaggerates the potential liability. Draining surface waters from impermeable surfaces and channeling the flow into a waterway in culverts and storm drains is not the manner in which surface water would naturally be discharged into a waterway. Both
Nor is the reasonable use rule one of strict liability. It requires consideration of all of the relevant circumstances, and anticipates that both the upstream riparian owner and the downstream owners will act reasonably. It does not, however, give defendants what they ask—an unqualified right to discharge surface water runoff in a manner that will cause downstream damage, and even destroy downstream property, without attempting reasonаble measures to prevent or minimize downstream damage.
Defendants offer no justification for a rule that would distinguish between the discharge of surface waters directly onto another owner’s property and the discharge into a natural waterway that ultimately has the same injurious effect. They seek instead absolute immunity for the discharge of surface water runoff into a natural watercourse whether or not they have reduced or eliminated the capacity of the ground to absorb normal rainfall, channeled the runoff into a single destructive outlet, or otherwise altered the volume and velocity of the waters discharged into the watercourse, and regardless of whether the watercourse is capable of carrying the increased flow of waters. In short, they seek to avoid the conclusion of Keys v. Romley (supra,
Defendants, who assume that Keys v. Romley, supra,
This court has restated the natural watercourse rule in several cases since Keys v. Romley, each of which involved an action against a municipal corporation or other governmental entity. In those cases, however, we have not considered whether that rule, as applied in this state, does include an element of reasonableness, or whether the rule of Keys v. Romley, supra,
Although this court has not considered the latter question, the Court of Appeal has done so in a series of decisions in whiсh,the court either assumed that the rule of reasonableness is applicable or expressly held it to be applicable to discharges into natural watercourses or flood control improvements in a watercourse. In Ektelon v. City of San Diego (1988)
In Martinson v. Hughey (1988)
In Weaver v. Bishop (1988)
The Court of Appeal reasoned in Weaver v. Bishop that neither the rule which gave a riparian owner absolute immunity for alteration in stream flow tо protect his property, nor the “common enemy doctrine” which permits an owner to protect himself against floodwaters, even by turning them onto another’s land, should apply. “The common enemy doctrine is one form of the ‘right to inflict damage,’ which was traditionally referred to under the [rubric] ‘damnum absque injuria’ (harm without legal injury). This notion, peculiar to water law, rested on the ‘generally perceived reasonableness’ of actions taken to protect one’s property and on a policy of encouraging the preservation of land resources. [Citation.] However the nearly unanimous trend has been away from per se rules based on categorical judgments of ‘generally perceived reasonableness,’ and toward fact-based determinations of reasonableness in the particular circumstances of each case.” (Weaver v. Bishop, supra,
“[A]s Keys acknowledges and illustrates, the general trend in water-damage cases is to replace the rigidities of property law with the more flexible, conduct-oriented principles of tort. (See
The Court of Appeal in this case reasoned that important policy reasons had initially supported the immunity doctrine and saw no compelling reason to: reject it, noting that it was bound in any case to follow the precedent established in Archer. The court observed that the Archer rule had been followed in Deckert v. County of Riverside (1981)
The Deckert opinion followed what that court believed to be the rule established in Archer and our subsequent decision in Bauer v. County of Ventura, supra,
By contrast, Weaver v. Bishop, supra,
We need not decide whether the natural watercourse rule applicable at the time of Archer, supra,
Although Keys v. Romley was decided in the context of damage caused to adjacent land by the discharge of surface waters, the reasoning of the court has broader applicability. The decision rests on the broad principle that a landowner may not act “arbitrarily and unreasonably in his relations with other landowners and still be immunized from all liability, [f] It is therefore incumbent upon every person to take reasonable care in using his property to avoid injury to [other] property . . . .” (Keys v. Romley, supra,
Defendants’ argument that Keys v. Romley is not and should not be applicable to discharge of surface waters into a natural watercourse overlooks the authority on which Keys v. Romley relied for the rule of reasonableness that it enunciated. That rule is derived from Armstrong v. Francis Corp. (1956)
The facts which gave rise to the New Jersey Supreme Court’s decision to abandon the common enemy/immunity rule in Armstrong v. Francis Corp., supra, 20 N.J. 320 [
The suggestion that the court would find the reasoning of Armstrong v. Francis Corp., supra,
In Swett v. Cutts (1870)
Most recently, the Missouri Supreme Court has brought all types of water within the rule of reasonableness. In Heins Implement Co. v. Hwy. & Transp. Com’n, supra,
Defendants have offered no persuasive reason to limit the requirement that landowners act reasonably with regard to one another to their treatment of surface water discharge onto adjacent property while permitting unreasonable conduct when the waters are discharged into a natural watercourse. Indeed, defendants appear to overlook the impact on their own interests of a rule which would afford them no recourse if a private developer discharged surface water runoff into a natural watercourse adjoining publicly owned property in a manner which undercut and washed away a portion of that property. We agree with plaintiffs, therefore, that the rule of Keys v. Romley applies to this dispute.
Under that rule: “The issue of reasonableness becomes a question of fact to be determined in each case upon a consideration of all the relevant circumstances, including such factors as the amount of harm caused, the foreseeability of the harm which results, the purpose or motive with which the possessor acted, and all other relevant matter. (Armstrong v. Francis Corp. (1956) supra, 20 N.J. 320.) It is properly a consideration in land development problems whether the utility of the possessor’s use of his land outweighs the gravity of the harm which results frоm his alteration of the flow of surface waters. [Citation.] The gravity of harm is its seriousness from an objective viewpoint, while the utility of conduct is meritoriousness from the same viewpoint. (Rest., Torts, § 826.) If the weight is on the side of him who alters the natural watercourse, then he has acted reasonably and
As we have shown above, however, the “well-settled civil law rule” dictates a different result for riparian owners than that applicable to upland owners. Under the Keys v. Romley rule, if both parties act reasonably with respect to draining surface waters onto adjacent property the upper owner will be liable for damage caused by the alteration of the natural flow of the water. The result will differ in disputes between riparian owners, each of whom acts reasonably. The civil law rule with respect to natural watercourses, unlike that applicable to draining surface waters onto adjacent property, immunizes the upper riparian owner for damage caused by the alteration of the natural discharge of surface water into a watercourse and by improvements in the stream bed. Therefore, if the upper owner acts reasonably, or if the lower owner has not acted reasonably to protect the property, the lower riparian owner must continue to accept the burden of damage caused by the stream water.
As we noted earlier, however, the reasonableness of a landowner’s action in discharging surface water runoff into a natural watercourse or in altering the watercourse itself cannot be determined in isolation. An owner in the lower reaches of a natural watercourse whose conduct has a relatively minor impact on the stream flow in comparison with the combined effect of actions by owners in the upper reaches of the watercourse may not be held liable for any damage caused by the stream flow beyond the proportion attributable to such conduct. If the rule were otherwise, owners at thе lowest reaches of a watercourse could preclude development of upstream property by imposing on a single upstream owner the cost of all damage caused by the addition of surface water runoff if that addition combined with the existing stream flow damaged the lowest properties. The purpose of both the civil law rule creating immunity for damage caused by surface water runoff onto adjacent property and the natural watercourse rule which imposed the burden of damage caused by upstream development on the downstream owner was to ensure that development of property would not be foreclosed by imposition of liability for damage caused by changes in the treatment of surface water occasioned by that development. Keys v. Romley and the application of the rule of reasonableness to natural watercourses further that purpose. The rules applicable to surface water runoff onto adjacent property or into a natural watercourse have been modified only by limiting the immunity created by the civil and common law rules to conduct that is reasonable.
V
Inverse Condemnation
The Court of Appeal held that substantial evidence supported the trial court’s conclusion that Reliez Creek was not a public improvement because respondents had not exercised control over the creek, had not erected structures other than the Sizeler outfall and sheet pile structure in it, and had not accepted the dedicated storm drainage easements. Therefore, the court held, notwithstanding the increased runoff into Reliez Creek caused by defendants’ streets, roads, and other public works, the natural watercourse rule also immunized respondents from liability in inverse condemnation for the damage to plaintiffs’ property. It did so because at common law a governmental entity, like a private party, had a right to collect surface waters on its land and discharge them into a natural watercourse.
Plaintiffs dispute both the conclusion that defendants could not be liable in inverse condemnation even if defendants’ use of Reliez Creek to drain their roads and other public works was unreasonable, and the conclusion that defendants’ actions with respect to the creek did not cause it to become a public work. Moreover, they argue, the question of public use is one to be decided as a matter of law by the appellate court, and the Court of Appeal erred in applying a substantial evidence standard of review. Finally, they argue that the Court of Appeal erred in holding that there can be no recovery against a public entity whose conduct contributed to the damage unless the plaintiff establishes the proportionate share of damage caused by that entity.
We agree with the Court of Appeal that plaintiffs’ evidence did not establish that Reliez Creek had become a public work. We also agree that none of the defendants is liable in inverse condemnation for the damage to
A. Conditional Privilege.
Article I, section 19 of the California Constitution permits private property to be “taken or damaged for public use only when just compensation . . . has first been paid to, or into court for, thе owner.” When there is incidental damage to private property caused by governmental action, but the governmental entity has not reimbursed the owner, a suit in “inverse condemnation” may be brought to recover monetary damages for any “special injury,” i.e., one not shared in common by the general public. When adopted as section 14 of article I of the 1879 Constitution this provision was construed as providing a broader right of recovery against a governmental entity for damage to private property than that available in an action against a private party. It was not necessary to prove negligence or the commission of another tort by the government. (Reardon v. City & County of San Francisco (1885)
In the arcane world of water law, however, the theory prevailed that if a private party had the right to inflict the damage, the government could assert the same immunity. Thus, notwithstanding article I, section 14 (now section 19), there could be no recovery against a governmental agency for damage caused by draining surface water onto adjacent property or into a natural watercourse in circumstances in which a private property owner had the right to do so. If the injury was damnum absque injuria as between private parties,
The injury was also considered damnum absque injuria if the governmental entity was acting in the proper exercise of its police powers, as when it acted to prevent future flood damage. “Where the police power is legitimately exercised, uncompensated submission is exacted of the property owner if his property be either damaged, taken, or destroyed. In the exercise of the power of eminent domain, compensated obedience for the taking or damaging of his property is the owner’s constitutional right. [][]... But while it is unquestionably true that the addition of the word ‘damaged’ to our constitutional law governing the exercise of the right of eminent domain gives in many instances a right to compensation which did not formerly exist, it did not, touching the exercise of the police power, give a right of action for damages which theretofore were damnum absque injuria." (Gray v. Reclamation District No. 1500 (1917)
This understanding of former section 14 of article I of our Constitution prevailed at the time Archer reached this court. There the court invoked the damnum absque injuria rule to relieve defendants from liability for the flooding caused by their alterations in the upstream drainage pattern and improvements in the watercourse. The court did so on the ground that a lower owner had no right to recover for damage caused by improvements construсted in a natural watercourse for the purpose of draining and protecting upper lands, and on the ground that defendants’ conduct was a proper exercise of the police power. The court unnecessarily and inexplicably also held that former section 14 of article I: “[P]ermits an action against the state, which cannot be sued without its consent. It is designed, not to create new causes of action, but to give a remedy for a cause of action that would otherwise exist.” (Archer, supra,
Reardon v. City & County of San Francisco, supra,
The Court of Appeal, and defendants, conclude that Albers, supra,
The general rule of Albers and the policy underlying former section 14 of article I were reaffirmed in Holtz v. Superior Court, supra,
Like Albers, Holtz did not involve the natural watercourse rule. Therefore, while we noted the recognition in past cases of an exception for exercise of the police power and the Archer exception for activities which were damnum absque injuria at common law (Holtz v. Superior Court, supra, 3 Cal.3d at pp. 305-306), we had no occasion in Holtz to consider the application of former section 14 of article I of the California Constitution beyond the facts of the case before us which involved excavations that withdraw lateral support from adjacent property. (
If anything, Holtz v. Superior Court, supra,
More recently we acknowledged the Archer exception in Belair v. Riverside County Flood Control Dist., supra,
Belair thus signalled not the continuation of the Archer exception, but its demise. It survived only vestigally in the limitation of inverse condemnation liability for public flood control projects in natural watercourses to damage resulting from a public entity’s unreasonable conduct. Thereafter, a public agency that acted unreasonably in regard to its use or alteration of a natural watercourse might be liable in inverse condemnation for downstream damage.
Because Belair involved only flood control projects, however, and we had acknowledged in Holtz v. Superior Court, supra,
While we did not decide in Holtz v. Superior Court, supra,
The Court of Appeal erred, therefore, in holding that a public entity may not be found liable in inverse condemnation for damage to private property caused by the manner in which surface water runoff from its property is discharged into a natural watercourse. Today neither a private owner nor a public entity has the right to act unreasonably with respect to other property owners. Neither may disregard the interests of downstream property owners, and a public entity may no longer claim immunity in tort or inverse condemnation actions.
This is not to say that public entities incur absolute liability for any damage caused by the runoff of surface water from improvements on its property into a natural watercourse or from public improvements constructed in or on a watercourse. Again, as we held in Belair v. Riverside County Flood Control Dist., supra,
Because a public agency, like any riparian property owner, engages in a privileged activity when it drains surface water into a natural watercourse or makes alterations to the watercourse, article I, section 19 of the California Constitution mandates compensation only if the agency exceeds the privilege by acting unreasonably with regard to other riparian owners.
B. Reasonable Conduct Standards.
The reasonableness of the public agency’s conduct must be determined on the facts of each case, taking into consideration the public benefit and the private damages in each instance. (Keys v. Romley, supra, 64 Cal.2d at pp. 409-410.) We note initially that runoff which would occur regardless of improvements on publicly owned property is not a basis for liability unless by collecting and discharging that runoff in an unreasonable manner, the improvement causes downstream property damage. Inverse condemnation liability ultimately rests on the notion that the private individual should not be required to bear a disproportionate share of the costs of a public improvement. Moreover, whether compensation must be paid for damages caused by
The factors which the court identified as important in imposing liability in Albers, supra,
As in Belair v. Riverside County Flood Control Dist, supra,
Keys v. Romley, supra,
(1) The overall public purpose being served by the improvement project; (2) the degree to which the plaintiff’s loss is offset by reciprocal benefits; (3)
Reasonableness in this context also considers the historic responsibility of riparian owners to protect their property from damage caused by the stream flow and to anticipate upstream development that may increase that flow. Keeping in mind the purpose of the constitutional right to compensation for damage caused by public works and improvements—that property owners contribute no more than their proper share to the public undertaking— plaintiff must demonstrate that the efforts of the public entity to prevent downstream damage were not reasonable in light of the potential for damage posed by the entity’s conduct, the cost to the public entity of reasonable measures to avoid downstrеam damage, and the availability of and the cost to the downstream owner of means of protecting that property from damage.
VI
Liability of Defendants
A. Status of Reliez Creek as Public Work.
Plaintiffs contend that the evidence they presented established that Reliez Creek has itself become a public work and, for that reason, City is liable in inverse condemnation for any damage it inflicts on their property. They argue that the Court of Appeal erred both in analyzing this claim under a substantial evidence standard of review, failing to recognize that public use is a question of law, and in concluding that City had not exercised control over the creek.
When trial is to the court, Code of Civil Procedure section 631.8 permits the court to grant a motion for judgment made by the defendant after plaintiff has completed presenting evidence. Since the trial court must weigh the evidence and may draw reasonable inferences from that evidence, such rulings are normally reviewed under the substantial evidence standard, with the evidence viewed most favorably to the prevailing party. However, if the facts are undisputed the reviewing court may make its own conclusions of law based on those facts. It is not bound by the trial court’s interpretation. (Torrey Pines Bank v. Hoffman (1991)
The Court of Appeal stated the standard as simply one according deference to the findings of the trial court, which are to be upheld if supported by substantial evidence. Nonetheless, we agree with the conclusion that plaintiffs did not establish that defendants, or any of them, exercised control over Reliez Creek and thereby transformed it into a public work or improvement. The evidence did not establish either an express or an implied acceptance of the drainage easements.
The evidence did not establish an exercise of control by any of the remaining defendants. County and District assisted the private riparian owners in obtaining federal financing and in design of the sheet pile structure, but those owners acknowledged responsibility for the structure. The public entities’ sponsorship was required to obtain financing, but no intent to exercise control or to incorporate the creek into a unified public drainage system is reflected by that involvement. The evidence that CalTrans constructed a box culvert in the creekbed viewed in light of the purpose for which it was constructed—to support the roadbed for Highway 24, which would otherwise have collapsed into the creekbed—and the effort to dissipate any increase in volume and velocity of the stream water demonstrate an intent to avoid interference with the creek, not to exercise control over it.
Utilizing an existing natural watercourse for drainage of surface water runoff and requiring other riparian owners to continue to do so does not transform the watercourse into a public storm drainage system. A governmental entity must exert control over and assume responsibility for maintenance of the watercourse if it is to be liable for damage caused by the streamflow on a theory that the watercourse has become a public work. (See, e.g., Souza v. Silver Development Co. (1985)
B. Liability of City, CalTrans, and BART.
The Court of Appeal held that, assuming the natural watercourse rule did not shield defendants, plaintiffs could not prevail insofar as they sought recovery from CalTrans and BART (which was a defendant only in the inverse condemnation cause of action) because they failed to establish that the facilities of these defendants were a substantial concurring cause of the downstream property damage and did not negate the possibility that urbanization generally would have resulted in the damage suffered by plaintiffs regardless of the actions of these defendants.
The trial court also found, and the Court of Appeal agreed, that plaintiffs’ evidence was insufficient to establish that, assuming those defendants could be held liable for damage caused by discharge of surface water runoff into Reliez Creek, either CalTrans or BART was a substantial concurring cause of the damage suffered by plaintiffs.
The evidence showed that BART owns only 3.5 acres in the Reliez Creek watershed. CalTrans occupies 22.4 acres. Together these entities occupy 25.9 acres or 1.1 percent of the watershed, and accounted for approximately 9.2 percent of the increase in surface water runoff over that which would have occurred even absent development or improvement of the property. The combined contribution of BART and CalTrans to the increased runoff due to urbanization in a 100-year storm, however, would be 6.7 percent of the total increase attributable to urbanization, and in a 2-year storm would be 7.2 percent. Those defendants would contribute less than 1 percent of the peak flow in a 100-year storm. The trial court concluded, based on these figures, that BART was responsible for only 0.02 percent of the runoff.
The expert was less positive as to whether the damage would have occurred without the contribution of both BART and CalTrans to the stream flow, but plaintiffs аlso failed to establish the proportion of damage attributable to CalTrans runoff from CalTrans property. Therefore, the Court of Appeal held, even assuming that together the BART/CalTrans runoff caused part of the damage,
Plaintiffs argue that the failure to apportion responsibility for the damage is irrelevant because defendants are subject to joint and several liability. We have held otherwise, however, with respect to apportionment of liability for damage caused by drainage of surface waters. In Mehl v. People ex rel. Dept. Pub. Wks. (1975)
Moreover, even were we to assume that the evidence was sufficient to establish that increased runoff from the property of either of these defendants was a substantial cause of plaintiffs’ damage and to permit an apportionment, plaintiffs’ failure to demonstrate that these defendants acted unreasonably, or that plaintiffs themselves acted reasonably to protect their property, precludes recovery.
That being so, we need not consider here whether a riparian property owner who has altered the natural drainage has a continuing obligation to monitor the impact of the runoff from the property as urbanization occurs, and, if necessary, to take steps to avoid damage if the changed conditions indicate that the runoff may be a substantial cause of future damage.
C. Liability of County and District.
Plaintiffs claim that the Court of Appeal also erred in upholding the nonsuit granted County and District by the trial court on the ground that neither owned or exercised control over any of the public works that may have contributed to plaintiffs’ damage. They note that there was evidence that County maintained at least one road in the watershed that drained into Reliez Creek as late as 1980, and argue further that ownership and control are not essential to their nuisance and trespass causes of action.
There is no error. Since the claim that Reliez Creek was part of a public drainage system fails, plaintiffs’ alternative theory that discharge of surface water runoff into Reliez Creek caused their damage must be considered. Plaintiffs point to no evidence that county owned property abutting Reliez Creek at the time plaintiffs suffered damage, however, and District never owned any of the properties which drain into Reliez Creek. These defendants are not liable for damage caused by runoff from property owned by others (see Preston v. Goldman (1986)
Therefore, while the Court of Appeal did not refer to the nuisance and trespass causes of action, it did not err in affirming the judgment for County and District. Giving plaintiffs’ evidence all the weight to which it is entitled, and drawing all legitimate inferences favorable to plaintiffs from that evidence, it is not sufficiently substantial to support a verdict for plaintiffs on those causes of action. (See Ewing v. Cloverleaf Bowl (1978)
The same is true with regard to the theory urged in this court, that by enforcing a City ordinance governing drainage and contracting with City to undertake and/or advise on erosion control, District became responsible for plaintiffs’ damage. Plaintiffs direct us to no evidence that tied any act of enforcement or performance of District’s contract with City to the damages suffered by plaintiffs in 1981-1982.
We also reject plaintiffs’ argument that the Court of Appeal erred in holding that County is not subject to tort liability as a party exercising ownership and control of the creekbed. County’s participation in sponsoring the application for federal funding of the sheet pile structure had no effect on ownership of the creekbed for purposes of establishing the tort liability of an owner of real property.
Finally, we note with regard to both tort and, inverse condemnation liability that the evidence reflects no efforts by plaintiffs themselves to protect their properties once it became apparent that erosion of the creek bank was occurring.
Costs
The trial court denied defendants’ motion for an award of costs made pursuant to Code of Civil Procedure section 1032
The Court of Appeal, relying on cases decided subsequent to Blau v. City of Los Angeles, supra,
Plaintiffs reason that, since the right to bring an inverse condemnation action is subsumed within the right to just compensation (Rose v. State (1942)
A property owner’s right to the costs of defending an eminent domain action is well established. “To require the defendants ... to pay any portion of their costs necessarily incidental to the trial of the issues on their part, or any part of the costs of the plaintiff, would reduce the just compensation awarded by the jury, by a sum equal to that paid by them for such costs.” (San Francisco v. Collins (1893)
More recently this court confirmed the right of a partially successful inverse condemnation plaintiff to costs in City of Los Angeles v. Ricards, supra,
Under the rules established by these cases it is clear that defendants’ costs may not be imposed on an inverse condemnation plaintiff in any case in which the plaintiff demonstrates that the actions of a governmental entity damaged the plaintiff’s property. Plaintiffs here do not fall within the rules of City of Los Angeles v. Ricards, supra,
Faced with a similar issue, the Court of Appeal applied the rule proposed in City of Los Angeles v. Ricards, supra,
We agree with the conclusion of the Court of Appeal in Smith v. County of Los Angeles, supra,
An inverse condemnation plaintiff must establish a compensable taking or damage before article I, section 19 of the California Constitutition may be invoked to shield the unsuccessful plaintiff from assessment of costs under Code of Civil Procedure section 1032. Nothing in the constitutional provision or our past cases suggests that a governmental entity must bear the expense of all litigation by property owners who in good faith, but without sufficient evidentiary or legal support, claim damаge to their property.
The statutory power of a court to impose costs of litigation on an unsuccessful party in a civil action is limited by article I, section 19 (San Francisco v. Collins, supra,
Lucas, C. J., Kennard, J., Arabian, J. and George, J., concurred. Panelli, J.,
Notes
Article I, section 19: “Private property may be taken or damaged for public use only when just compensation, ascertained by a jury unless waived, has first been paid to, or into court for, the owner. . . .”
Plaintiffs have not sought recovery under the Fifth Amendment to the United States Constitution in this action.
Less than 7 percent of the property in the watershed is owned by defendants. Numerous other public and private entities are owners of riparian property upstream from plaintiffs.
In support of a claim that defendants were aware that development in the watershed posed a danger to downstream properties, plaintiffs introduced a 1952 study prepared by the Contra Costa County Flood Control and Water Conservation District, a study authorized by the Board of Supervisors of Contra Costa County. The study predicted increased flood hazard as
The “storm drainage system in and about the City of Lafayette” was alleged to be comprised of “pipelines, culverts, trenches, sewers, runouts, and waterways, including those portions of Reliez Creek adjoining Plaintiffs’ real property.”
Negligence claims against the private parties were settled before trial.
Article I, section 19: “Private property may be taken or damaged for public use only when just compensation, ascertained by a jury unless waived, has first been paid to, or into court for, the owner. . . .”
A 920-foot concrete box culvert had been constructed beneath the BART/CalTrans roadway in place of the original stream bed; a 100-foot long “sheet pile” structure had been placed in the channel in an attempt to control erosion; the “Sizeler outfall” structure, an apron of boulders bound together by concrete, was placed below the outfall of a City-owned storm drain which extended into the creek; and channel armoring had been placed at the location of the Sizeler outfall. Repairs bn the Sizeler outfall were performed by a City contractor.
District acted on behalf of plaintiffs in seeking federal funds from the Soil Conservation Service (SCS) to make repairs to the creek. SCS does not accept applications directly from affected property owners. It requires a local sponsor. District acted as such, and assisted in designing the sheet pile structure, a structure consisting of steel sheet pilings lining both sides of the creek for a distance of 100 feet. SCS funded 80 percent of the cost, the affected homeowners the remaining 20 percent; and City funded a portion of the structure within the right-of-way of Condit Road, a City-owned street. District solicited construction bids, awarded the contract, made all field inspections during construction and performed the final inspection as part of its responsibility to assist County and local entities in planning drainage matters. It did not own the sheet pile structure, however. The homeowners assumed future maintenance responsibility for the structure on their portion of the creek and acknowledged in their agreement with District that the structure did not belong to County or District.
A city or county must require the dedication of drainage easements as a condition precedent to the approval of either a tentative or a final subdivision map. (Gov. Code, § 66478.5.) Basements on two parcels owned by plaintiffs were dedicated to County on final subdivision maps, but were not accepted by County. City took no action to accept or reject the easements dedicated to it. (See Gov. Code, § 66477.1.) They claim on that basis that those drainage easements are not public property. A storm drainage easement on the property of plaintiff Sizeler was originally accepted by County, which maintained the storm drain on that easement until it passed to City upon incorporation in 1968. City has cleared fallen trees and other obstructions in the creek, actions which plaintiffs argued reflected implied acceptance of the easements through the exercise of control and dominion over the easements and the creek.
One final subdivision map described the easements it created as follows; “The areas marked SDB, storm drain easement and PUB are storm drain easements and are dedicated to the City of Lafayette or its designee and to the public for public use for storm, flood and surface water drainage, including construction access or maintenance of works, improvements and structures whether covered or open for the clearing of obstructions and vegetation and the exercise of the rights provided for within said storm drain easements areas shall be considered prior in time and paramount to any rights exercised by the homeowners of this subdivision
See Government Code sections 815, 830, and 810.8. Under the California Tort Claims Act, of which these sections are a part, the tort liability of a governmental entity is statutory. Under these sections liability may exist if the condition of publicly owned property “creates a substantial (as distinguished from a minor, trivial or insignificant) risk of injury when such property or adjacent property is used with due care in a manner in which it is reasonably foreseeable that it will be used.” (Gov. Code, § 830, subd. (a).) Property damage is an “injury” within the meaning of that section. (Gov. Code, § 810.8.)
Because plaintiffs failed to comply with the claims requirements of the Governmental Tort Liability Act (see Gov. Code, § 900 et seq.), the trial court ruled that plaintiffs could not pursue this cause of action against BART.
Trial was to the court on the inverse condemnation cause of action. Special and directed verdicts in favor of City were returned by the jury on the tort causes of action insofar as these structures were involved.
Plaintiffs did not dispute this ruling on appeal, but did contend that the existence of the structures was evidence relevant to whether Reliez Creek had become a public improvement.
The court acceptеd plaintiffs’ theory that if a public entity transforms a natural creek channel into a storm drainage system the creek is no longer a natural watercourse, but is an artificial public improvement.
As to County, the court found that as of 1968 only 28 percent of the watershed had been developed. There were dedicated easements from subdivisions in the area, but those easements had not been formally accepted. The evidence did not establish that County had exerted
The court conceded that the question was closer with respect to City, but found that the evidence did not establish that City had impliedly accepted easements or exercised dominion and control to the extent that the creek had become a part of a storm drainage system.
The combined CalTrans and BART contribution to the increased flow into Reliez Creek was 9.2 percent. BART’s acreage constituted only .01 percent of the watershed, and its improvements contributed only .02 percent to the increased flow of surface waters into Reliez Creek.
The expert testimony did not differentiate BART responsibility for plaintiffs’ damage from that attributed to CalTrans. The trial court ruled that evidence of the amount of damage each caused was necessary at the liability phase in order to establish that a public entity’s actions satisfied the “substantial concurring cause” element of an inverse condemnation cause of action, and for that reason also found the evidence insufficient as to BART and CalTrans.
While recognizing that the Court of Appeal was bound by Belair, plaintiffs also argued that if they were not entitled to recover on grounds that defendants’ conduct was unreasonable within the meaning of that decision, Belair was incorrectly decided to the extent that it relied on Archer. Archer, they argued, had been overruled by subsequent cases and conflicted with the language and policy of article I, section 19 of the California Constitution.
As described in one treatise, “The natural flow rule, or as it is sometimes called, the ‘civil law’ rule, originated in Louisiana and Pennsylvania. It ‘places a natural easement or servitude upon the lower land for the drainage of surface water in its natural course and the natural flow of the water cannot be obstructed by the servient owner.’
“The way the civil law rule works is that an upper landowner has a right as landowner to the natural drainage of diffused surface waters onto the lower property in the form of a ‘natural’ servitude. This means the lower owner has a duty to respect that right and if the lower owner interferes, the upper owner has a claim against the lower owner. But, in turn, the upper owner may be a lower owner in relation to someone else. Furthermore, if the scope of the servitude is exceeded, that is, surcharged, the lower neighbor will have a claim against the upper owner. The fact that flow creates a ‘natural’ easement refers only to the way in which the ‘easement’ arose. The treatment of natural flow as a servitude invokes the entire body of easement law and gives the natural flow right stature as an interest in real property; therefore, a legislative body may be more restricted by the constitution in dealing with it.” (5 Waters and Water Rights (Beck ed. 1991) § 59.02(b)(2), p. 505, fns. omitted.)
We need not decide if this statement of the rule was consistent with the generally applicable civil law rule governing natural watercourses, and with prior California law. That rule, too, may have been limited to discharges which did not increase the volume or accelerate the flow of water in a watercourse beyond that produced by natural runoff of surface waters. (See LeBrun v. Richards, supra,
Several cities and counties, appearing as amici curiae in support of defendants, also urge retention of the natural watercourse rule. Among their concerns is fear that liability may be imposed for downstream damage that is alleged to be a product of discretionary approval of development. While the issue of liability solely for approving development of private property is not before us in this case, we note that public entities enjoy broad statutory immunity for such acts. (See, e.g., Gov. Code, §§ 818.2, 818.4, 821.)
Contrary to the argument of defendants, we did not cite Archer with approval in Holtz v. Superior Court (1970)
And, far from reaffirming the Archer rule in Belair v. Riverside County Flood Control Dist., supra,
As we pointed out in Keys v. Romley, supra,
One need not abandon concepts of property law to reach the result of Keys v. Romley, supra,
The extent of the upper landowner’s easement for drainage and protection is that which the parties might reasonably expect from the future normal development of the dominant tenement. (Camp Meeker Water System, Inc. v. Public Utilities Com. (1990)
These considerations are relevant to whether a landowner’s conduct is reasonable.
The Court of Appeal also held that City had statutory immunity under Government Code section 818.4 for approving permits which allowed upstream development to occur. Plaintiffs argue that the holding overlooks exceptions to that immunity for dangerous conditions on public property. We understand their argument to be that, because upstream development permitted by City has resulted in a dangerous condition of public property, the public entity is not immune for damage caused by that dangerous condition. The Court of Appeal did not hold otherwise. It cоrrectly stated the statutory rule that a public entity is not liable for injury caused by the issuance of a permit.
The Court of Appeal did not address plaintiffs’ argument that public roads and surfaces impervious to water, which increased surface water runoff into a natural watercourse, were a “dangerous condition” which contributed to plaintiffs damage. Our conclusion that plaintiffs failed to establish damage caused by unreasonable conduct of defendants in permitting the increased runoff makes it unnecessary to address that argument here.
Gray v. Reclamation District No. 1500, supra,
The Albers view of former section 14 of article I, and our conclusion here that public entities may be liable for downstream damage under present section 19, are wholly consistent with, and carry out the intent of, the delegates to the 1878-1879 constitutional convention.
The initial draft of former section 14 did not include the “or damaged” provision. That provision was added by an amendment offered by delegate Hager who, like delegate Estee who spoke in support of the amendment, believed that “a man should not be damaged without compensation.” (3 Debates & Proceedings, Cal. Const. Convention 1878-1879, p. 1190.) The example of damage relied on in support of the amendment was an incident in San Francisco when, pursuant to legislative authorization, Second Street was cut, leaving adjacent homes “high in the air, and wholly inaccessible.” (Ibid.)
The only argument in opposition to the amendment was that the measure was untried and might be construed to compel compensation of lost profits if a road were moved. There is no suggestion in the debate on the measure that the delegates anticipated that immunity would exist for damage inflicted in any exercise of the police power or that a damnum absque injuria doctrine would immunize a governmental entity.
We question, moreover, whether requiring and/or accepting drainage easements across private property to a privately owned natural watercourse is evidence of an exercise of control over the watercourse itself. The requirement may reflect nothing more than a precaution necessary to ensure that drainage of surface waters into the watercourse is not cut off by the improvements.
The Court of Appeal reached a similar conclusion with respect to City, County, and District, reasoning that there was no evidence that City maintained any structures which were a substantial concurring cause of the damage.
This expert testified that in a 100-year storm, the combined CalTrans/BART contribution to the stream flow would be less than 1 percent (.93 percent). Its impact on stream velocity was “small.”
This conclusion makes it unnecessary to address plaintiffs’ argument that the Court of Appeal failed to consider Government Code section 895.2, which imposes joint and several liability on governmental entities that cause injury for which they would incur liability under any other law while performing under an agreement between or among the governmental entities.
Furthermore, the relevance, if any, of Government Code section 895.5 was not raised by plaintiffs in the briefs they filed in the Court of Appeal.
Code of Civil Procedure section 1032, subdivision (b), provides that “[ejxcept as otherwise expressly provided by statute, a prevailing party is entitled as a matter of right to recover costs in any action or proceeding.”
Retired Associate Justice of the Supreme Court sitting under assignment by the Chairperson of the Judicial Council.
Concurrence Opinion
I concur in the holding and much of the reasoning of the majority. The majority correctly adopt the requirement that upstream and downstream riparian owners act reasonably, in the same manner in which the reasonableness requirement for the discharge of surface waters was explicitly recognized in Keys v. Romley (1966)
In this case, plaintiffs offered expert testimony that runoff from City streets, and from Highway 24 operated by Caltrans, was a substantial cause of increased flow of Reliez Creek and of the resultant flooding. Such evidence would ordinarily be significant enough for us to remand the case to the trial court for a full adjudication of the causation issue. However, as the majority rightly conclude, plaintiffs failed to prove the other elements necessary for making their case: that the public entities acted unreasonably, and that plaintiffs took reasonable measures to protect their own property.
The lack of such evidence of reasonableness in this particular case, however, should not mislead public entities. Today’s opinion, in adopting a reasonableness requirement for upstream riparian owners, and in reaffirming the cost-spreading rationale behind inverse condemnation liability, clearly puts public entities on notice that they are responsible for monitoring and mitigating the effects of the cumulative development of streets and highways on downstream riparian owners.
According to the principles enunciated by the majority today, downstream property owners would be able to prevail against a public entity in inverse condemnation liability if they are able to show: (1) that runoff from public streets and highways substantially contributed to the damage of the downstream owners’ property; (2) that the owners took reasonable measures to protect their own property; and (3) that the public entities responsible for the streets and highways failed to adopt reasonable measures to mitigate the foreseeable effects of such development. The precise meaning of “reasonable” mitigation measures in this context remains to be delineated on a case-by-case basis.
Appellants’ petition for a rehearing was denied April 13, 1994.