dissenting: The City of Lancaster and the Lancaster City Sewer Authority, referred to jointly herein as appellants, in early December 1977, filed a timely appeal from a letter of the Department of Environmental Resources dated November 23, 1977, notifying appellants that the North Sewage Treatment Plant was determined by the DER to be hydraulically overloaded and as a result appellants were required to comply with the requirements of section 94.21 of the DER’s rules and regulations, 25 Pa. Code §94.21. On December 30, 1977, the Home Builders Association (intervenor) was granted permission to intervene.
*170A motion for summary judgment was filed by appellants on January 10, 1978, wherein they requested this board to declare the November 23, 1977, action of the DER to be null and void for the following two reasons:
1. The hydraulic load on the sewage treatment plant is within the limits permitted by the plant’s National Pollution Discharge Elimination System (NPDES) permit and thus the plant is not overloaded; and
2. Section 94.21 is unlawful and unreasonable.10
Intervenor joined in the motion for summary judgment and alleged as a further basis for granting the motion that the action was violative of the due process clauses of the United States and Pennsylvania Constitutions because the action was taken by the DER without prior notice and hearing.
For the purpose of deciding the motion for summary judgment, the factual basis of the DER’s November 23,1977, letter and all reasonable inferences to be drawn therefrom must be accepted as true. Cf. Schacter v. Albert, 212 Pa. Superior Ct. 58, 239 A. 2d 841 (1968). Thus, the DER’s contention that the North Sewage Treatment Plant is hydraulically overloaded is accepted as true. A hydraulic overload is defined by §94.1, 25 Pa. Code §94.1, as follows: “Hydraulic Overload — The condition that occurs when the hydraulic portion of the load, as measured by the average daily flow entering a sewage treatment plant, exceeds the average *171daily flow upon which the permit and the plant design are based or when the flow in any portion of the system exceeds its hydraulic carrying capacity [during a recent 3-month period].”
Initially, appellants’ contention that the NPDES permit allows the existing flow should be summarily dismissed as a basis for summary judgment. It is apparent from a review of the documents filed with the board and from oral argument on the motion that there are material issues of fact in dispute on, inter alia, the requirements of the NPDES permit and the requirements of the permit required by section 202 of The Clean Streams Law of June 22, 1937, P.L. 1987, as amended, 35 P.S. §691.1 et seq. If genuine issues as to material facts exist, then a case must go to trial: Rose v. Food Fair Stores Inc., 437 Pa. 117, 262 A. 2d 851 (1970).
In challenging the validity of section 94.1 appellants are faced with the same burden as challenging the validity of a statute. The Commonwealth Court in Com. v. Metzger, 22 Pa. Commonwealth Ct. 70, 347 A. 2d 743 (1975), expressed the pertinent principles:
“The regulations challenged here, of course, are legislative in character, for they were issued pursuant to a grant of legislative power contained in Section 9 of the Sewage Facilities Act, 35 P.S. §750.9. Thus, they are subject to the same test with reference to their validity as in an act of the Legislature, Uniontown Area School District v. Pennsylvania Human Relations Commission, 455 Pa. 52, 313 A. 2d 156 (1973), and a heavy burden, therefore, rests upon the person asserting their unconstitutionality: Bilbar Construction Company v. Easttown Township Board of Adjustment, 393 Pa. *17262, 141 A. 2d 851 (1958). As our Supreme Court has said:
“ ‘A court, in reviewing such a regulation, “is not at liberty to substitute its own discretion for that of administrative officers who have kept within the bounds of their administrative powers .... Error or unwisdom is not equivalent to abuse. What has been ordered must appear to be ‘so entirely at odds with fundamental principles ... as to be the expression of a whim rather than an exercise of judgment.’ ” American Telephone & Telegraph Co. v. United States, 299 U.S. 232, 236-37 [57 S. Ct. 170, 172], 81 L. Ed. 142 (1936).’ Uniontown Area School District, supra, 455 Pa. at 77, 313 A. 2d at 169 Id. 22 Pa. Commonwealth Ct. at 73, 347 A. 2d 746.”
The Pa. Supreme Court in Water and Power Resources Board v. Green Springs Co., 394 Pa. 1, 145 A. 2d 178 (1958), stated the test to which the validity of a statute is subjected: “ ‘Nothing but a clear violation of the Constitution will justify the judiciary in nullifying a legislative enactment. Every presumption must be indulged in its favor, and one who claims an Act is unconstitutional has a very heavy burden of proof . . . ’ if the statutory language be of doubtful import the statute in its entirety and all its provisions must be considered.” Id. 394 Pa. at 6, 145 A. 2d at 181. See also Com. v. Delenick, 24 Pa. Commonwealth Ct. 577, 357 A. 2d 736 (1976).
Appellants focus their objections on the third paragraph of the requirements imposed by section 94.21, which prohibits new extensions of, or connections to, a sewer system tributary to the overloaded treatment plant except as approved by the DER.
*173The regulation does not affect the appellants’ right to construct an extension to the sewer system. Whether or not a hydraulic overload exists at the treatment plant, the construction of an extension of the sewage system is prohibited by section 207 of The Clean Streams Law11, supra, without the approval of the DER. Thus, even prior to the November 23, 1977, action of the DER, appellants were prohibited from the construction of an extension of the sewage system without the DER approval.
The issue before this board therefore is the validity of a regulation requiring a person to seek the DER approval prior to connecting to a sewer system.
The legislature has given the DER the authority to prohibit connections to sewer systems without the DER’s prior approval. Section 202 of The Clean Streams Law, supra, states as follows:
“No municipality or person shall discharge or permit the discharge of sewage in any manner, directly or indirectly, into the waters of this Commonwealth unless such discharge is authorized by *174the rules and regulations of the board or such person or municipality has first obtained a permit from the department. . . For the purposes of this section, a discharge of sewage into the waters of the Commonwealth shall include a discharge of sewage by a person or municipality into a sewer system or other facility owned, operated or maintained by another person or municipality and which then flows into the waters of the Commonwealth. A discharge of sewage without a permit or contrary to the terms and conditions of a permit or contrary to the rules and regulations of the board is hereby declared to be a nuisance.” (Emphasis supplied.)
Under section 202, therefore, the DER has the authority to prohibit all connections without the DER approval. In F. & T. Construction Co. v. DER, 6 Pa. Commonwealth Ct. 59, 293 A.ad 138 (1972), the Commonwealth Court stated: “The Department has clearly been given the power to prevent the discharge of sewage into a sewer system by the Clean Streams Law. . .” Section 94.21, which only requires the DER approval if an overload exists, is, therefore, less restrictive than permitted by Section 202 of The Clean Streams Law.
As appellants have chosen to attack the regulation by means of a motion for summary judgment, there is no evidence of record that this requirement is unduly oppressive or burdensome nor is there any evidence of record that the requirement constitutes an unreasonable exercise of the police power as apphed to appellants. Notwithstanding the want of such critical evidence to support the heavy burden of proof required of one who challenges the validity of a regulation issued pursuant to a grant of legislative power, appellants would have us declare section 94.21 invalid because it constitutes “the dele*175gation of unlimited discretion to an administrative agency.” Appellants contend that section 94.21 allows the DER unbridled discretion to ban all connections to their sewer system as long as the hydraulic overload exists. DER could, appellants argue, use section 94.21 to circumvent the requirements of sections 94.31, 94.3212, and 94.3313 of the DER’s regulations, 25 Pa. Code 94.31, 94.32 and 94.33, which set forth the conditions which must exist before the DER can impose a ban on connections to a sewage system and which require the DER to publish notice of the imposition of aban.
The DER does not have unlimited discretion to prohibit connections to a sewer system under section 94.21. The existence of ahydraulic overload, as defined by section 94.1, requires property owners to seek the DER approval prior to installing a connection to the sewage system. However, the DER’s approval or denial of connections to the sewer system under 94.21(3) does involve the DER’s discretion. See East Pennsboro Twp. Authority v. DER, 18 Pa. Commonwealth Ct. 58, 334 A. 2d 798 (1975). Where the DER has discretion to act, its *176discretion is limited by the policies and requirements of The Clean Streams Law, including the limitations imposed on the DER by section 4, Declaration of Policy and section 5, Powers and Duties, of The Clean Streams Law, supra. DER’s “exercise of discretion” when it approves or denies a connection to a sewer system is reviewable by this board on appeal by an aggrieved party.
There is nothing in this record which would allow us to conclude that the DER will use section 94.21 to circumvent the requirements imposed on the DER prior to imposing a ban under sections 94.31, 94.32, and 94.33.14
A regulation cannot be declared invalid because of the mere possibility of abuse by the DER. The Commonwealth Court in Bortz Coal Co. v. Com., 2 Pa. Commonwealth Ct. 441, 279 A. 2d 388 (1971), stated in answer to the contention that the Pennsylvania Air Pollution Control Act of January 8, 1960, P.L. (1959) 2119, as amended, 35 P.S. §4001 et seq., constituted an unlawful delegation of legislative authority to the Air Pollution Commission that:
“One of the discretionary determinations to be made by the Commission is the scientific or technical rules and regulations which determine that *177amount of air pollution which should be prohibited in carrying out the legislative intent. If the regulatory agency sets forth unreasonable standards or fails to establish any standards of air pollution, the citizens are protected through the appeal provisions of the Act. Certainly the possibility of such an unreasonable determination should not be the basis for a holding that there has been an unlawful delegation of power. As stated before, we hold that there is not an unlawful delegation of powers in the Air Pollution Control Act.” Id. 2 Pa. Commonwealth Ct. at 449, 279 A. 2d at 394. (Emphasis in original.)
In summary, section 94.21(3) does not, by itself, prohibit connections to a hydraulically overloaded sewage system; rather it requires prior DER approval of the connection. It is, of course, true that the power to approve is the power to deny. However, I don’t believe we should assume that the DER will act unreasonably in reviewing requests for approval to connect. Certainly, an unreasonable action by the DER is reviewable by this board and reversible as an abuse of discretion.
Therefore since: (1) DER has the authority to require a party to seek its approval before connecting to a sewage system; (2) There are no facts of record on which to base a finding that DER will employ section 94.21 in an unreasonable manner; (3) Appellants have not met the heavy burden required by DER v. Metzger, supra, to declare a regulation invalid; and (4) This board cannot declare a regulation invalid on the mere possibility it will be abused by the DER, I would dismiss appellants’ motion for summary judgment.
. An amicus curiae brief has been filed in support of appellants’ motion for summary judgment by the Williamsport Sanitary Authority.
. Section 207 of The Clean Streams Law states:
“All plans, designs, and relevant data for the construction of any new sewer system, or for the extension of any existing sewer system, by a municipality, or for the erection, construction, and location of any treatment works or intercepting sewers by a person or municipality, shall be submitted to the board for its approval before the same are constructed or erected or acquired. Any such construction or erection which has not been approved by the board by written permit, or any treatment works not operated or maintained in accordance with the rules and regulations of the board, is hereby also declared to be a nuisance and abatable as herein provided.”
. §94.32 states:
“A ban may be imposed by the Department whenever the Department finds that such a ban is needed in order to prevent or ehminate public health hazards or pollution resulting from violations of the Clean Streams Law not otherwise covered by the provisions of this Chapter.”
. §94.33 states:
“(a) A ban imposed by order of the Department will be addressed to the person or municipality who authorizes connection to the sanitary sewer system and who operates the sanitary sewer system and plant. The ban shall be effective immediately upon receipt of the order imposing the ban. ...”
. In fact, counsel for DER asserts in his brief on this matter that the DER has not yet prohibited any person from connecting to the system, since no property owner has petitioned for approval to connect to the system. See appellee’s supplemental brief in opposition to appellants’ motion for summary judgment, p. 6.