At common law, a municipality was, under certain circumstances, immune from liability for the torts it committed. See, e.g., Abbot v. Bristol, 167 Conn. 143, 150 and n. 2, 355 A.2d 68 (1974); Carta v. Norwalk, supra, 108 Conn. 701-702; Hourigan v. Norwich, 77 Conn. 358, 364-65, 59 A. 487 (1904). The source of this municipal immunity was the state's sovereign immunity.

In addition, we observe that the defendant appears to have adopted the plaintiff's dual characterization of its functions—those in relation to its supply of water being proprietary and those in relation to its provision of recreational space being governmental—although it disagrees as to which function the plaintiff's allegations of negligence relate. The defendant therefore has neither challenged this court's prior decisions that the supply of water is proprietary whenever revenues are generated thereby; see Martel v. Metropolitan District Commission, supra, 275 Conn. at 53, 881 A.2d 194;Abbott v. Bristol, 167 Conn. 143, 150, 355 A.2d 68 (1974); Hourigan v. Norwich, 77 Conn. 358, 364–66, 59 A. 487 (1904); nor asserted that the allegations in the present case relate to its statutory duty to construct and maintain public roads under the special act that chartered the defendant. See 20 Spec. Acts 1204, No. 511, § 2 (1929).

The municipal operation of a water utility for corporate profit is a proprietary function. See Abbott v. Bristol, 167 Conn. 143, 150, 355 A.2d 68 (1974); Richmond v. Norwich, supra, 588; Hourigan v. Norwich, 77 Conn. 358, 364-66, 59 A. 487 (1904). A municipal entity is subject to liability pursuant to § 52-557n (a) (1) (B), however, only if its allegedly tortious conduct was inextricably linked to a proprietary function.

The plaintiff's claim, rather, is that the alleged conduct did not constitute governmental acts because it concerned a proprietary, as opposed to a public activity, namely, the operation of a water utility. In support of her claim, the plaintiff relies upon three cases involving negligence actions arising out of a municipality's operation of a water utility: Hourigan v. Norwich, 77 Conn. 358, 59 A. 487 (1904); Richmond v. Norwich, 96 Conn. 582, 115 A. 11 (1921); and Abbot v. Bristol, 167 Conn. 143, 355 A.2d 68 (1974). In each of those cases, this court concluded that the municipal defendants could not avail themselves of immunity because the municipalities engaged in the allegedly tortious actions for the sake of corporate gain rather than for the administration of government.

Unlike the present case, in each of those cases, the allegedly tortious conduct of the municipalities was inextricably linked to the operation of the water utility for corporate gain.Elliott, at 413, citing Hourigan v. Norwich, 77 Conn. 358 (1904); Richmond v. Norwich, 96 Conn. 582 (1921); and Abbott v. Bristol, 167 Conn. 143 (1974). There must be a direct link, then, between the municipal authority and the pecuniary benefit.

Other courts have found the relationship between quasi-independent boards and the municipality sufficient to support the municipality's liability for a board's torts. Hourigan vs. Norwich, 59 A. 487 (Conn. 1904); Fine vs. Mayor Council of Wilmington, 94 A.2d 393 (Del. 1953); St. Germain vs. Fall River, 59 N.E. 447 (Mass. 1901); Reed vs Syracuse, 120 N.W. 180 (Neb. 1909); Seeley vs. Amsterdam, 66 N.Y.S. 221 (N Y App. Div. 1900).

At such a proceeding the burden of proof is on the defendant to disprove those allegations of the complaint which he contests. Hourigan v. Norwich, 77 Conn. 358, 367-68, 59 A. 487 (1904). If the defendant simply claims that he is not liable, he assumes the burden of proving that fact. Bernhard v. Curtis, 75 Conn. 476, 481, 54 A. 213 (1903). If the defendant sustains his burden, the plaintiff is entitled to nominal damages only. Cardona v. Valentin, supra, 26." DeBlasio v. Aetna Life Casualty Co., supra, 401-402.

These facts the defendant must prove, and in the absence of any proof, or of sufficient proof to legally satisfy the court, judgment for substantial damages must follow. Hourigan v. Norwich, 77 Conn. 358, 362, 367; Brennan v. Berlin Iron Bridge Co., 74 id. 382, 387; Finken v. Elm City Brass Co., 73 id. 423, 427; Ockershausen v. New York, N. H. H.R. Co., 71 id. 617, 621. In this case the complaint alleges (1) that the plaintiff was a passenger riding in the smoking-car of a train which left South Norwalk at 11:15 P. M., which train stopped near the Main Street crossing in Bridgeport, and the plaintiff, believing the train had reached the Bridgeport station where he had intended to alight, rose from his seat and started toward the rear of the car, and when within a few feet of the rear door the train was violently started and the plaintiff thereby was thrown from the door, striking the outside platform, from which he fell through an open gateway which ordinarily encloses the platform while the train is in motion and at other times except when the train is at a station, and fell under and was run over by the wheels of one of the cars of said train; (2) that by being thus thrown from the car the

Id., 850. In the course of distinguishing between governmental and proprietary acts, the court stated: "This court explained in Hourigan v. Norwich [ 77 Conn. 358, 364, 59 A. 487 (1904)], that when the state performs its governmental function through an agent, `the agent cannot be sued for injuries resulting from a strict performance of the agency. In such case the act is regarded as the act of the [s]tate and not that of the agent, who is the mere instrument of the [s]tate and nothing more. . . .' Similarly, a municipality is the agent of the state `in the exercise of certain governmental powers . . . [and when] the [s]tate imposes upon an incorporated city the absolute duty of performing some act which the [s]tate may lawfully perform and pertaining to the administration of government, the city in the performance of that duty may be clothed with the immunities belonging to the mere agent of the [s]tate. . . . '" Considine v. Water-bury, supra, 279 Conn. 841.

The source of this municipal immunity was the state's sovereign immunity. Hourigan v. Norwich, 77 Conn. 358, 364-65, 59 A. 487 (1904); see 18 E. McQuillin, Municipal Corporations (3d Ed. Rev. 2003) § 53.23, p. 380 ("rule of immunity for governmental acts and liability for corporate or proprietary acts is grounded in common-law sovereign immunity"). The state may, however, abrogate common-law municipal immunity by statute, which it has done, to some extent, by passing § 7-465.