Opinion
Plaintiffs Max and Harry Holtz seek a writ of mandate to compel the Superior Court of the City and County of San Francisco to reinstate certain allegations stricken from their complaint upon motion of defendants San Francisco Bay Area Rapid Transit District (BART) and the City and County of San Francisco. Plaintiffs own improved real property fronting on Market Street in San Francisco, and in their first amended complaint in the underlying action they allege that, as a result of the extensive excavation of Market Street undertake® by defendant BART in connection with its construction of an underground rapid transit system, their land and buildings have been substantially damaged.
Specifically, plaintiffs claim that the excavation of the land adjacent to the northern boundary of their property, reaching a depth of 80 feet, caused the lateral support of their land to be withdrawn, with the consequence that portions of their land moved downward and laterally onto the defendant city’s property, so that plaintiffs’ buildings and other improvements settled and cracked. Plaintiffs sought recovery for the damage incurred on two distinct theories: (1) In count one of their complaint plaintiffs claimed that defendants were “strictly liable,” i.e., Hable without negligence, on a theory of inverse condemnation for the physical injuries proximately resulting from the construction of the public improvement as *300deliberately planned and designed; (2) In the second count plaintiffs alternatively claimed that defendants had been negligent in the excavation activities and were thus liable for damages which were proximately caused by this negligence. Plaintiffs prayed for $30,000 damages to both the land and the improvements in each of the two counts of the complaint.
After the court overruled defendants’ general demurrer to both causes of action, defendants moved to strike those allegations of the complaint alleging damage to the building and improvements. In support of this motion, defendants relied on section 832 of the Civil Code, which sets out the general mutual rights and duties of coterminous owners with respect to lateral and subjacent support. 1 Defendants argued that section 832 rendered an excavating coterminous owner hable for damages to a neighbor’s improvements only if the foundation of the neighbor’s improvement equalled or exceeded the “standard depth,” then defined as 12 feet;2 since the complaint revealed that the depth of the foundations of *301plaintiffs’ buildings were only six feet, defendants claimed that they could not be liable for damages to the buildings or improvements and requested that such allegations be stricken. The trial court correctly concluded that section 832 does not absolve a negligent excavator from liability even if his neighbor’s foundation does not reach “standard depth” and thus it denied the motion to strike with respect to the negligence count. The court granted the motion to strike with respect to the initial “strict liability” inverse condemnation count, however, apparently concluding that section 832 establishes the limits of liability for damages resulting from the withdrawal of lateral support when such damage is caused by public entities as well as when it is caused by private coterminous owners.3
(See fn. 4) Plaintiffs now seek a writ of mandate to compel the trial court to reinstate the stricken allegations,4 contending that the trial court’s order conflicts with prevailing inverse condemnation principles.5 *302For the reasons discussed below, we conclude that defendant public entities may be liable on an inverse condemnation theory for the alleged physical damage to plaintiffs’ property proximately caused by the excavation as deliberately planned and designed without a showing of negligence.
Defendants’ primary contention, as we understand it, is that since under section 832 a private excavating coterminous owner would not be liable, absent negligence, for the damage incurred by plaintiffs in this case, defendants, though public agencies, should likewise not be liable unless negligent. In thus equating the liability of public and private entities, defendants ignore, however, the distinct constitutional source of a public entity’s responsibility to compensate for damages resulting from the construction of a public improvement and overlook the unique purpose of the inverse condemnation duty. Article I, section 14, of the California Constitution, provides that: “Private property shall not be taken or damaged for public use without just compensation. . . .” and it is this provision, rather than section 832, in which plaintiffs’ inverse condemnation claim is fundamentally rooted. (See Rose v. State of California (1942) 19 Cal.2d 713, 724 [123 P.2d 505].) In such cases the purposes of the constitutional clause, rather than the limits established by a rule of statutory or common law allocating rights and responsibilities between private parties, must fix the extent of a public entity’s responsibility.
In Albers v. County of Los Angeles (1965) 62 Cal.2d 250 [42 Cal. Rptr. 89, 398 P.2d 129], this court explicitly rejected the notion that there need be a congruence between public and private liability in inverse condemnation actions. Considerable physical damage to plaintiffs’ homes had resulted in Albers from a landslide caused by the county’s construction of a road; the landslide was completely unforeseeable, however, and the trial court explicitly found that the county had not been negligent in the construction of the road. The county, relying on a rather substantial body of cases,6 argued that since a private party would not be liable for unforeseeable damages, the county, on these facts should likewise be free from a duty to compensate.
After undertaking an extensive review of all of our inverse condemnation cases, we concluded in Albers that the decisions declaring that “[i]f *303the property owner would have no cause of action were a private person to inflict the damage, he can have no claim of compensation from the state” (Archer v. City of Los Angeles (1941) 19 Cal.2d 19, 24 [119 P.2d 1]), had stated “the rule . . . much more broadly than required. . . .” (62 Cal.2d at p. 260); we reaffirmed the vitality of earlier precedent which stated that “the right assured to the owner by this provision of the constitution is not restricted to the case where he is entitled to recover as for a tort at common law. If he is consequently damaged by the work done, whether it is done carefully and with skill or not, he is still entitled to compensation under this provision.” (62 Cal.2d at p. 257, quoting Reardon v. City & County of San.Francisco (1885) 66 Cal. 492, 505 [6 P. 317].)7 On the facts of Albers itself we proceeded to affirm a judgment rendering the county liable for the actual physical damage proximately caused by its construction, and we generalized our holding by establishing that, with only two exceptions (to be discussed below) “any actual physical injury to real property proximately caused by the improvement as deliberately designed and constructed is compensable under article I, section 14, of our Constitution whether foreseeable or not.” (62 Cal.2d at pp. 263-264.) (Italics added.)
As the Albers opinion carefully made clear, its general rule of compensability did not derive from statutory or common law tort doctrine, but instead rested on the construction, “as a matter of interpretation and policy” (62 Cal.2d at p. 262), of our constitutional provision. The relevant “policy” basis of article I, section 14, was succinctly defined in Clement v. State Reclamation Board (1950) 35 Cal.2d 628, 642 [220 P.2d 897]: “The decisive consideration is whether the owner of the damaged property if uncompensated would contribute more than his proper share to the public undertaking.” In other words, the underlying purpose of our constitutional provision in inverse—as well as ordinary—condemnation is “to distribute throughout the community the loss inflicted upon the individual by the making of public improvements” (Bacich v. Board of Control (1943) 23 Cal.2d 343, 350 [144 P.2d 818]): “to socialize the burden . . . —to afford relief to the landowner in cases in which it is unfair to ask him to bear a burden that should be assumed by society” (Mandelker, Inverse Condemnation: The Constitutional Limits of Public Responsibility, 1966 Wis.L.Rev. 3, 8).
In announcing our holding in Albers in the generalized form quoted *304above, while of course most fundamentally influenced by this “loss distribution” premise,8 we did not overlook the competing considerations which caution against an open-ended, “absolute liability” rule of inverse condemnation. Recognizing that “fears have been expressed that compensation, allowed too liberally, will seriously impede, if not stop, beneficial public improvements because of the greatly increased cost” (Bacich v. Board of Control (1943) 23 Cal.2d 343, 350 [144 P.2d 818]), we deemed it prudent to focus our policy inquiry.on situations which shared a general factual similarity with that present in Albers. Thus we limited our holding of inverse condemnation liability, absent fault, to “physical injuries of real property” that were “proximately caused” by the improvement as deliberately constructed and planned. We have no occasion in the instant case to analyze the operation of article I, section 14, beyond the limits suggested by the facts of Albers; here plaintiffs clearly allege that they have suffered “actual physical injuries of real property” and that such injuries “were proximately caused by the excavation and construction work . . . [as] deliberately desigried and constructed by defendants. . . .”9
Thus, under Albeds interpretation of article I, section 14, the present plaintiffs clearly should be compensated for the damage to their land and improvements resulting from the BART excavation, notwithstanding the limits section 832 may place on a private party’s liability, unless the instant case falls within either of two doctrinal categories which were expressly excepted from Alber’s generalized strict liability rule. In attempting to reconcile earlier inverse condemnation cases in Albers, we identified two strains of decisions in which the urgency or particular importance of the governmental conduct involved was so overriding that considerations of public policy inveighed against a rule rendering the acting public *305entity liable absent fault. The first exception, the Gray exception (Gray v. Reclamation Dist. No. 1500 (1917) 174 Cal. 622 [163 P. 1024]), involved noncompensable damages “inflicted in the proper exercise of the police power”; the second exception, the Archer exception (Archer v. City of Los Angeles (1941) 19 Cal.2d 19, 24 [119 P.2d 1]), encompassed those cases in which the state at common law “had the right to inflict the damage.” (Albers v. County of Los Angeles (1965) 62 Cal.2d 250, 262 [42 Cal.Rptr. 89, 398 P.2d 129].) (Italics in original.)
Defendants do not, and could not, properly contend that their excavation and construction activity in the instant case falls within the “police power” exception referred to in Albers. As we explained fully in Rose v. State of California (1942) 19 Cal.2d 713, 730-731 [123 P.2d 505], the “police power” doctrine “[generally . . . operates in the field of regulation,” rendering “damages” occasioned by the adoption of administrative or legislative provisions noncompensable (e.g., Hadacheck v. Sebastian (1915) 239 U.S. 394 [60 L.Ed. 348, 36 S.Ct. 143] (reduction in property value resulting from zoning ordinance need not be compensated); Chicago & Alton R.R. Co. v. Tranbarger (1915) 238 U.S. 67 [59 L.Ed. 1204, 35 S.Ct. 678] (statute requiring railroads to construct drainage ditches along their tracks at their own expense does hot constitute a compensable taking)); this doctrine of noncompensable loss comes into play in connection with more direct “taking” or “damaging” of property only under “emergency” conditions; i.e., when damage to private property is inflicted by government “under the pressure of public necessity and to avert impending peril.” (House v. Los Angeles Flood Control Dist. (1944) 25 Cal.2d 384, 391 [153 P.2d 950].) Recognizing that a broad interpretation of this doctrine of noncompensable loss would completely vitiate the constitutional requirement of just compensation (Rose v. State of California (1942) 19 Cal.2d 713, 731 [123 P.2d 505]), the courts have narrowly circumscribed the types of emergency that will exempt the public entity from liability.10 From the present pleadings we find no indication that the “police power” exception could possibly be applicable in the instant case (Cf. Youngblood v. Los Angeles Flood Control Dist. (1961) 56 Cal.2d 603 [15 Cal.Rptr. 908, 364 P.2d 840]; Bauer v. Ventura County (1955) 45 Cal.2d 276 [289 P.2d 1]).
Defendants do contend, however, that the instant litigation falls within *306the second exception referred to in Albers, the “Archer exception.” In analyzing the Archer decision in Albers we found that “the [Archer] court held that a private riparian owner would have had a right to collect the surface waters on his land and channel them into the stream into which they would naturally drain even though this resulted in the flooding of lower lands. Based on this fundamental premise, the court was not required to go further than to hold that article I, section 14, did not require the state to pay for damages which it had a right at common law to cause.” (62 Cal.2d at pp. 260-251.) (Italics in original.)
Defendants argue that since under the circumstances of the instant case, section 832 permits a private coterminous owner to excavate on his own property without incurring liability as long as he is not negligent, he has a “right” to inflict damages-within the meaning of the Archer exception, and by analogy a governmental agency has a similiar “right” to inflict such damage. That interpretation of the “right” referred to in the Archer exception, however, would so expand the exception as to consume the general Albers rule. Under such an interpretation, whenever damage was caused by a nonnegligent act for which a private individual would not be liable, the private party could be designated as having a “right” to inflict such injury. If we held that the public entity possessed such a parallel “right,” the doctrine that public responsibility is to be equated with private liability, which Albers explicitly disapproved, would be resurrected through the Archer exception. Indeed, our holding in Albers itself refutes the defendants’ broad reading of the “right to inflict damage” concept. In Albers we assumed that a private party would not have been liable for the resulting unforseeable damages (in defendants’ terminology, a private person had a “right” to inflict such damages) (see 62 Cal.2d at p. 262, fn. 3), but we still found the public agency responsible under the constitutional provision.
The fulfillment of the broad “cost spreading” purpose of the constitutional provision, as clarified in Albers, requires a limited application of the Archer exception rather than defendants’ proposed expansive one. The doctrine of the common law “right to inflict damage,” emanating from the complex and unique province of water law, has been employed in only a few restricted situations, generally for the purpose of permitting a landowner to take reasonable action 'to protect his own property from external hazards such as floodwaters. (E.g., Clement v. State Reclamation Board (1950) 35 Cal.2d 628, 635-636 [220 P.2d 897]; Lamb v. Reclamation Dist. No. 108 (1887) 73 Cal. 125, 129-131 [14 P. 625].) In some ways the language of the “right to inflict damage” projects a misleading concept, because the essential common characteristic of this category of cases is not *307that they all involve the infliction of injury on others, but rather that they all involve injury resulting from the landowner’s efforts to protect his own property from damage. In recognition of the generally perceived reasonableness of such action and, as a policy matter, to encourage protective measures to preserve land resources,11 certain types of protective measures were cloaked in a legal “privilege.”12 (Lamb. v. Reclamation District No. 108 (1887) 73 Cal. 125, 129-130 [14 P. 625]; Gray v. Reclamation Dist. No. 1500 (1917) 174 Cal. 622, 651 [163 P. 1024]; San Gabriel Valley Country Club v. County of Los Angeles (1920) 182 Cal. 392 [188 P. 554, 9 A.L.R. 1200]; Archer v. City of Los Angeles (1941) 19 Cal.2d 19 [119 P.2d 1].) We need neither examine the continued validity of any of these long-lived doctrines, nor question the applicability of the policies supporting the “privileged” status of a particular private activity in the context of public improvements,13 for we know of no case, and have *308been directed to none,14 in which the activity involved in the instant action—the excavation of land to construct an improvement—has ever been conceived of as privileged activity.
On the contrary, courts in jurisdictions which have a “just compensation” clause comparable to California’s have held that damages inflicted by street excavations upon property of abutting landowners are the kind of damages which most appropriately should be borne by the governmental entity, whether or not it engaged in negligent excavation. The discussions of two textwriters, which the Alberts opinion quoted at length (62 Cal.2d at pp. 259-260), make this point rather lucidly. Thus Nichols, in his treatise on Eminent Domain, concludes: “Common law liability is undoubtedly an indication of damage; but lack of liability at common law should not conclusively prove that there is no damage under the constitutional provision. Accordingly, courts are inclined to allow compensation for actual physical injury to land regardless of the fact that it was actionable at common law, and in the case of injury to abutting property arising from a particular use of the street in front of it to disregard the test of common law liability altogether.” (Italics added.) (2 Nichols on Eminent Domain (3d ed. 1963) § 6.441 [2], p. 494.) The discussion in American Jurisprudence reiterates this conclusion: “In cases of special and peculiar damage arising out of physical injury to property, courts are inclined to allow compensation although the injury is one that would not be actionable *309at common law if inflicted by an adjoining owner. In cases arising out of injury to abutting property by alterations or erections in a street, the question whether a private owner might lawfully make similar alterations or erections on his own land without liability to his neighbors is never even considered.” (Italics added.) (10 Am.Jur., Eminent Domain, § 138, pp. 764-765.)
A careful review of the case law of our sister states reveals the accuracy of the textwriters’ general observations. (See Cuneo v. City of Chicago (1942) 379 Ill. 488 [41 N.E.2d 473] (damage resulting from non-negligent excavation of street compensable under constitutional compensation clause); City of Covington v. Parsons (1935) 258 Ky. 22 [79 S.W.2d 353] (same); Bator v. Ford Motor Co. (1934) 269 Mich. 648 [257 N.W. 906] (same); Siemers v. St. Louis Elec. Terminal Ry. Co. (1938) 343 Mo. 1201 [125 S.W.2d 865] (same); In re Mill Creek Sewer (1953) 374 Pa. 120 [97 A.2d 11, 12] (same); Kunst v. City of Grafton (1910) 67 W.Va. 20 [67 S.E. 74] (same); Farnandis v. Great Northern Ry. Co. (1906) 41 Wash. 486 [84 P. 18, 20] (same); cf. In re Board of Rapid Transit R.R. Comrs. of City of New York (1909) 197 N.Y. 81 [90 N.E. 456, 464] (same result reached under “just compensation” statute).)
Indeed Reardon v. City & County of San Francisco (1885) 66 Cal. 492 [6 P. 317], the seminal California decision construing the current “or damaged” wording of article I, section 14, as imposing liability for compensation absent fault, involved public activity and private damage closely analogous to that present in the instant case. In Reardon, the state, in the process of constructing a sewer and grading a street, piled heavy rocks, stones, and earth on the street; as a result of the increased pressure exerted by the weight of this heavy material, “the subjacent earth was squeezed and pressed downward and outwards, causing the displacement and the destruction of the foundation” of the plaintiffs’ buildings located on the abutting property (66 Cal. at p. 495). The court held that plaintiffs could recover for the damages so sustained, notwithstanding the fact that they could not have prevailed against a private party under common law principles.
The damages allegedly incurred by the instant plaintiffs are of precisely the same nature as those at issue in Reardon. 15 Although the government action precipitating the damage in Reardon is factually distinguishable *310from the excavation undertaken by the present defendants, defendants have suggested no persuasive basis for attributing any legal significance to this factual distinction.16 We can perceive of no policy considerations that would justify differentiating, for purposes of our constitutional “just compensation” clause, damages inflicted in tunnel excavations from those caused by sewer construction.
Our decision in the instant case, and the Albers decision more generally, in effect recognize that, under article I, section 14, physical damages proximately resulting from a public improvement must be considered as direct a “cost” as the property actually condemned or the materials actually utilized in its construction. Indeed, in most instances a public entity may be able to forestall unintended physical damage by initially employing more protective measures in the actual construction of the project; in the instant case, for example, defendants could probably have prevented the damage to plaintiffs’ property by expending additional funds in shoring up its excavation. This comment does not imply, however, that defendants would necessarily be negligent in not expending such funds; the likelihood of the damage may have been so remote and the expense of the additional protection so great that it was reasonable (hence, non-negligent) for defendants to forego supplemental measures initially. Nevertheless, since the undertaking of the excavation at this lower cost created some risk, however slight, of damage to plaintiffs’ property, it is proper to re*311quire the public entity to bear the loss when damage does occur.17 “[I]n the generality of cases, the governmental entity with its superior resources is in a better position to evaluate the nature and extent of the risks of public improvement than are potentially affected property owners, and ordinarily [the governmental entity] is the more capable locus of responsibility for striking the best bargain between efficiency and cost (including inverse liability costs) in the planning of such improvements.” (Van Alstyne, Inverse Condemnation: Unintended Physical Damage (1969) 20 Hastings L.J. 431, 495.)
In sum, we conclude that, in accordance with the general inverse condemnation principles set out in Albers, the instant plaintiffs will be entitled to compensation under article I, section 14, for “any physical injury to real property proximately caused by the improvement as deliberately designed and constructed.” Thus the trial court erred in striking allegations of such physical injury from the initial count of their complaint.
The peremptory writ of mandate shall issue.
Wright, C. J., McComb, J., Peters, J., Mosk, J., Burke, J., and Sullivan, J., concurred.