dissenting.
I must respectfully dissent to the Majority’s conclusion that this Court must assume original jurisdiction over certain claims asserted by Pastore and transfer his remaining claims to the Court of Common Pleas of Erie County. In so concluding, the Majority mischaracterizes the nature of Pastore’s action thereby resulting in a misapplication of Section 761 of the Judicial Code, as amended, 42 Pa.C.S. § 761. The Majority states that this action is primarily one in equity based upon alleged violations of a statutory duty under the Storm Water Management Act (Storm Act), Act of October 4, 1978, P.L. 864, 32 P.S. §§ 680.1-680.17 and that this Court shall assume jurisdiction over all claims set forth in Counts I, II and III of the complaint, except those claims based upon common law negligence or nuisance.
Pastore sets forth three possible theories of recovery. Count I is based upon Edinboro’s status as a successor in interest to Porreco and negligence committed by Porreco before Edinboro acquired his property; County II is based upon Edinboro’s negligence in altering the land acquired from Porreco increasing the surface water runoff; and Count III sets forth Edinboro’s alleged violation of the storm water management agreement between Maleno and Porreco which, according to Pastore, runs with the land. In.each count, Pastore demands damages and injunctive relief. Pastore’s allegations clearly demonstrate that he is primarily seeking damages caused by flooding of his property due to an increase and alteration of storm and surface water runoff.1
*128The fact that Pastore seeks injunctive relief, in addition to his claims for damages, does not provide a basis for this Court’s assumption of original jurisdiction because this action constitutes an action conducted pursuant to provisions govern- ' ing the waiver of sovereign immunity under Section 761(a)(1)(iii) and “an action or proceeding in the nature of trespass” as to which the Commonwealth government formerly enjoyed sovereign or other immunity under Section 761(a)(1)(v). The Majority concludes, however, that to the extent Pastore bases his claims upon violation of the Storm Act, this Court has original jurisdiction because those claims are not founded upon common law negligence and therefore are not in the nature of trespass.
The Majority’s conclusion is contrary to the principle established in Balshy v. Rank, 507 Pa. 384, 490 A.2d 415 (1985), in which the Pennsylvania Supreme Court rejected the argument that an action brought under 42 U.S.C. §§ 1983, 1985 are not actions in the nature of trespass under Section 751(a)(1)(v) because they are based upon statutory and not common law remedies. After explaining the historical basis for Section 761(a)(1)(v), the Court held that Sections 1983 and 1985 created a species of tort liability and provided remedies available to plaintiffs “in an action for damages” and that actions against the Commonwealth or its officers for money damages, whether based upon statutory or common law liability, are outside this Court’s original jurisdiction.
Section 16(b) of the Storm Act, 32 P.S. § 680.16(b), provides that “[i]t is hereby declared to be the purpose of this act to provide additional and cumulative remedies to abate nuisances.” Section 13, 32 P.S. § 680.13, sets forth obligations of landowners engaged in the alteration of land to implement measures reasonably and necessary to prevent injury to health, safety or other property; and under Section 15, 32 P.S. § 680.15, any person injured due to violations of the Storm Act can recover damages in an action at law and may further seek injunctive relief in an action in equity. At common law, *129property owners have a cause of action for damages to their property resulting from the increased flow of surface water caused by an artificial use of adjoining land. Westbury Realty Corp. v. Lancaster Shopping Center, Inc., 396 Pa. 383, 152 A.2d 669 (1959). Therefore, Pastore’s action, whether based upon provisions of the Storm Act or common law negligence, constitutes an action in the nature of trespass under Section 761(a)(1)(v) and consequently deprives this Court of original jurisdiction over Pastore’s claims.
Moreover, where an action turns on the same legal question, an action in equity may be joined with an action at law. Meara v. Hewitt, 455 Pa. 132, 314 A.2d 263 (1974). Where an adequate legal remedy exists, it is appropriate for a court in equity to transfer the case to the law side of the court for disposition. Fawber v. Cohen, 516 Pa. 352, 532 A.2d 429 (1987). Also, an action in equity is inappropriate where the measure of damages in trespass actions is flexible enough to properly recompense the plaintiffs. Id. Thus, this Court may properly transfer the entire case sub judice to the trial court for its disposition.2
In addition, Pa.R.C.P. No. 1020(d) provides that if a transaction or occurrence gives rise to more than one cause of action against the same person, they shall be joined in separate counts in the action against any such person. Failure to assert a cause of action under this mandatory joinder rule *130results in a waiver of that claim. Hineline v. Stroudsburg Electric Supply Co., 402 Pa.Superior Ct. 178, 586 A.2d 455, appeal denied, 528 Pa. 630, 598 A.2d 284 (1991). The purpose of this rule is to insure that a cause of action arising out of the same transaction or occurrence be tried together in the same action to prevent piecemeal litigation. Id. Pastore complied with this mandatory joinder rule and set forth three theories of recovery in the complaint. However, the Majority splits the causes of action and creates a result which is inimical to the purposes of Rule 1020.
A clear example of the anomaly presented by splitting the causes of action for trial purposes is shown by this Court’s decision to transfer to the trial court all claims based upon common law negligence and to assume jurisdiction over those claims based upon violation of the storm water management agreement, although Pastore is seeking damages caused by a single harm, i.e., flooding from the increased storm and surface water flow. In this situation, evidence for assessing damages under either theory of tort or breach of contract, would be duplicative; it therefore becomes evident that two separate trial proceedings required by this Court’s decision would neither serve judicial economy nor otherwise comply with mandates of the Judicial Code. I would therefore transfer the entire case to the trial court for its disposition.
KELLEY, J., joins in this dissent.. An action at law and an action in equity are merely forms of actions, and a choice of form does not determine the question of jurisdiction. West Homestead Borough School Dist. v. Allegheny County Board of School Directors, 440 Pa. 113, 269 A.2d 904 (1970). See also Gedekoh v. Peoples Natural Gas Co., 183 Pa.Superior Ct. 511, 133 A.2d 283 (1957).
. The term "action or proceeding” under Section 761 of the Judicial Code includes the entire case arising out of a single or series of transactions or occurrences, and judicial economy is advanced by permitting a comprehensive disposition of litigation in one proceeding. Department of General Services v. Frank Briscoe Co., 502 Pa. 449, 466 A.2d 1336 (1983). Section 931(a) of the Judicial Code, 42 Pa.C.S. § 931(a), provides that "[ejxcept where exclusive original jurisdiction of an action or proceeding’ is ... vested in another court of this Commonwealth, the courts of common pleas shall have unlimited jurisdiction of ‘all actions and proceedings,’ including all actions and proceedings heretofore cognizable by law or usage in the courts of common pleas.” Applying the definition of "action or proceeding” to this case, the trial court inevitably has original jurisdiction over the entire case whether arising out of a single or a series of transactions or occurrences.