Justice Rehnquist
delivered the opinion of the Court.
When this litigation was first before us we recognized the existence of a federal “common law” which could give rise to a claim for abatement of a nuisance caused by interstate water pollution. Illinois v. Milwaukee, 406 U. S. 91 (1972). Subsequent to our decision, Congress enacted the Federal Water Pollution Control Act Amendments of 1972. We granted cer-tiorari to consider the effect of this legislation on the previously recognized cause of action. 445 U. S. 926.
I
Petitioners, the city of Milwaukee, the Sewerage Commission of the city of Milwaukee, and the Metropolitan Sewerage Commission of the County of Milwaukee, are municipal corporations organized under the laws of Wisconsin. Together they construct, operate, and maintain sewer facilities serving Milwaukee County, an area of some 420 square miles with a population of over one million people. The facilities consist of a series of sewer systems and two sewage treatment plants located on the shores of Lake Michigan 25 and 39 miles from the Illinois border, respectively. The sewer systems are of both the “separated” and “combined” variety. A separated sewer system carries only sewage for treatment; a combined sewer system gathers both sewage and storm water runoff and transports them in the same conduits for treatment. On occasion, particularly after a spell of wet weather, overflows occur in the system which result in the discharge of sewage directly into Lake Michigan or tributaries leading into Lake Michigan. The overflows occur at discrete discharge points throughout the system.
Respondent Illinois complains that these discharges, as well as the inadequate treatment of sewage at the two treatment plants, constitute a threat to the health of its citizens. Pathogens, disease-causing viruses and bacteria, are allegedly discharged into the lake with the overflows and inadequately treated sewage and then transported by lake currents to Illinois waters. Illinois also alleges that nutrients in the sewage accelerate the eutrophication, or aging, of the lake. Respondent Michigan intervened on this issue only.
Illinois’ claim was first brought to this Court when Illinois sought leave to file a complaint under our original jurisdiction. Illinois v. Milwaukee, supra. We declined to exercise original jurisdiction because the dispute was not between two States, and Illinois had available an action in federal district court. The Court reasoned that federal law applied to the dispute, one between a sovereign State and political subdivisions of another State concerning pollution of interstate waters, but that the various laws which Congress had enacted “touching interstate waters” were “not necessarily the only federal remedies available.” Id., at 101, 103. Illinois could appeal to federal common law to abate a public nuisance in interstate or navigable waters. The Court recognized, however, that:
“It may happen that new federal laws and new federal regulations may in time pre-empt the field of federal common law of nuisance. But until that time comes to pass, federal courts will be empowered to appraise the equities of the suits alleging creation of a public nuisance by water pollution.” Id., at 107.
On May 19, 1972, Illinois filed a complaint in the United States District Court for the Northern District of Illinois, seeking abatement, under federal common law, of the pub-blic nuisance petitioners were allegedly creating by their discharges.
Five months later Congress, recognizing that “the Federal water pollution control program . . . has been inadequate in every vital aspect,” S. Rep. No. 92-414, p. 7 (1971), 2 Legislative History of the Water Pollution Control Act Amendments of 1972 (Committee Print compiled for the Senate Committee on Public Works by the Library of Congress), Ser. No. 93-1, p. 1425 (1973) (hereinafter Leg. Hist.), passed the Federal Water Pollution Control Act Amendments of 1972, Pub. L. 92-500, 86 Stat. 816. The Amendments established a new system of regulation under which it is illegal for anyone to discharge pollutants into the Nation’s waters except pursuant to a permit. §§ 301, 402 of the Act, 33 U. S. C. §§ 1311, 1342 (1976 ed. and Supp. III). To the extent that the Environmental Protection Agency, charged with administering the Act, has promulgated regulations establishing specific effluent limitations, those limitations are incorporated as conditions of the permit. See generally EPA v. State Water Resources Control Board, 426 U. S. 200 (1976). Permits are issued either by the EPA or a qualifying state agency. Petitioners operated their sewer systems and discharged effluent under permits issued by the Wisconsin Department of Natural Resources (DNR), which had duly qualified under § 402 (b) of the Act, 33 U. S. C. § 1342 (b) (1976 ed. and Supp. Ill), as a permit-granting agency under the superintendence of the EPA. See EPA v. State Water Resources Control Board, supra, at 208. Petitioners did not fully comply with the requirements of the permits and, as contemplated by the Act, §402 (b)(7), 33 U. S. C. § 1342 (b)(7), see Wis. Stat. Ann. § 147.29 (West 1974), the state agency brought an enforcement action in state court. On May 25,1977, the state court entered a judgment requiring discharges from the treatment plants to meet the effluent limitations set forth in the permits and establishing a detailed timetable for the completion of planning and additional construction to control sewage overflows.
Trial on Illinois’ claim commenced on January 11, 1977. On July 29 the District Court rendered a decision finding that respondents had proved the existence of a nuisance under federal common law, both in the discharge of inadequately treated sewage from petitioners’ plants and in the discharge of untreated sewage from sewer overflows, The court ordered petitioners to eliminate all overflows and to achieve specified effluent limitations on treated sewage. App. to Pet. for Cert. F-25 — F-26. A judgment order entered on November 15 specified a construction timetable for the completion of detention facilities to eliminate overflows. Separated sewer overflows are to be completely eliminated by 1986; combined sewer overflows by 1989. The detention facilities to be constructed must be large enough to permit full treatment of water from any storm up to the largest storm on record for the Milwaukee area. Id., at D-l. Both the aspects of the decision concerning overflows and concerning effluent limitations, with the exception of the effluent limitation for phosphorus, went considerably beyond the terms of petitioners’ previously issued permits and the enforcement order of the state court.
On appeal, the Court of Appeals for the Seventh Circuit affirmed in part and reversed in part. 599 F. 2d 151. The court ruled that the 1972 Amendments had not pre-empted the federal common law of nuisance, but that “[i]n applying the federal common law of nuisance in a water pollution case, a court should not ignore the Act but should look to its policies and principles for guidance.” Id., at 164. The court reversed the District Court insofar as the effluent limitations it imposed on treated sewage were more stringent than those in the permits and applicable EPA regulations. The order to eliminate all overflows, however, and the construction schedule designed to achieve this goal, were upheld.
II
Federal courts, unlike state courts, are not general common-law courts and do not possess a general power to develop and apply their own rules of decision. Erie R. Co. v. Tompkins, 304 U. S. 64, 78 (1938); United States v. Hudson & Goodwin, 7 Cranch 32 (1812). The enactment of a federal rule in an area of national concern, and the decision whether to displace state law in doing so, is generally made not by the federal judiciary, purposefully insulated from democratic pressures, but by the people through their elected representatives in Congress. Wallis v. Pan American Petroleum Corp., 384 U. S. 63, 68 (1966). Erie recognized as much in ruling that a federal court could not generally apply a federal rule of decision, despite -the existence of jurisdiction, in the absence of an applicable Act of Congress.
When Congress has not spoken to a particular issue, however, and when there exists a “significant conflict between some federal policy or interest and the use of state law,” Wallis, supra, at 68, the Court has found it necessary, in a “few and restricted” instances, Wheeldin v. Wheeler, 373 U. S. 647, 651 (1963), to develop federal common law. See, e. g., Clearfield Trust Co. v. United States, 318 U. S. 363, 367 (1943). Nothing in this process suggests that courts are better suited to develop national policy in areas governed by federal common law than they are in other areas, or that the usual and important concerns of an appropriate division of functions between the Congress and the federal judiciary are inapplicable. See TV A v. Hill, 437 U. S. 153, 194 (1978); Diamond v. Chakrabarty, 447 U. S. 303, 317 (1980); United States v. Gilman, 347 U. S. 507, 511-513 (1954). We have always recognized that federal common law is “subject to the paramount authority of Congress.” New Jersey v. New York, 283 U. S. 336, 348 (1931). It is resorted to “[i]n absence of an applicable Act of Congress,” Clearfield Trust, supra, at 367, and because the Court is compelled to consider federal questions “which cannot be answered from federal statutes alone,” D’Oench, Duhme Co. v. FDIC, 315 U. S. 447, 469 (1942) (Jackson, J., concurring). See also Board of Commissioners v. United States, 308 U. S. 343, 349 (1939); United States v. Little Lake Misere Land Co., 412 U. S. 580, 594 (1973); Miree v. DeKalb County, 433 U. S. 25, 35 (1977) (Burger, C. J., concurring in judgment). Federal common law is a “necessary expedient^” Committee for Consideration of Jones Falls Sewage System v. Train, 539 F. 2d 1006, 1008 (CA4 1976) (en banc), and when Congress addresses a question previously governed by a decision, rested on federal common law the need for such an unusual exercise of lawmaking by federal courts disappears. This was pointedly recognized in Illinois v. Milwaukee itself, 406 U. S., at 107 (“new federal laws and new federal regulations may in time pre-empt the field of federal common law of nuisance”), and in the lower court decision extensively relied upon in that case, Texas v. Pankey, 441 F. 2d 236, 241 (CA10 1971) (federal common law applies “[u]ntil the field has been made the subject of comprehensive legislation or authorized administrative standards”) (quoted in Illinois v. Milwaukee, supra, at 107, n. 9).
In Arizona v. California, 373 U. S. 546 (1963), for example, the Court declined to apply the federal common-law doctrine of equitable apportionment it had developed in dealing with interstate water disputes because Congress, in the view of a majority, had addressed the question:
“It is true that the Court has used the doctrine of equitable apportionment to decide river controversies between States. But in those cases Congress had not made any statutory apportionment. In this case, we have decided that Congress has provided its own method for allocating among the Lower Basin States the mainstream water to which they are entitled under the Compact. Where Congress has so exercised its constitutional power over waters, courts have no power to substitute their own notions of an ‘equitable apportionment’ for the apportionment chosen by Congress.” Id., at 565-566.
In Mobil Oil Corp. v. Higginbotham, 436 U. S. 618 (1978), the Court refused to provide damages for “loss of society” under the general maritime law when Congress had not provided such damages in the Death on the High Seas Act:
“We realize that, because Congress has never enacted a comprehensive maritime code, admiralty courts have often been called upon to supplement maritime statutes. The Death on the High Seas Act, however, announces Congress’ considered judgment on such issues as the beneficiaries, the limitations period, contributory negligence, survival, and damages. . . . The Act does not address every issue of wrongful-death law, . . . but when it does speak directly to a question, the courts are not free to ‘supplement’ Congress’ answer so thoroughly that the Act becomes meaningless.” Id., at 625.
Thus the question was whether the legislative scheme “spoke directly to a question” — in that case the question of damages — not whether Congress had affirmatively proscribed the use of federal common law. Our “commitment to the separation of powers is too fundamental” to continue to rely on federal common law “by judicially decreeing what accords with ‘common sense • and the public weal’ ” when Congress has addressed the problem. TV A v. Hill, supra, at 195.
Contrary to the suggestions of respondents, the appropriate analysis in determining if federal statutory law governs a question previously the subject of federal common law is not the same as that employed in deciding if federal law pre-empts state law. In considering the latter question “ 'we start with the assumption that the historic police powers of the States were not to be superseded by the Federal Act unless that was the clear and manifest purpose of Congress.’ ” Jones v. Rath Packing Co., 430 U. S. 519, 525 (1977) (quoting Rice v. Santa Fe Elevator Corp., 331 U. S. 218, 230 (1947)). While we have not hesitated to find pre-emption of state law, whether express or implied, when Congress has so indicated, see Ray v. Atlantic Richfield Co., 435 U. S. 151, 157 (1978), or when enforcement of state regulations would impair “federal superintendence of the field,” Florida Lime & Avocado Growers, Inc. v. Paul, 373 U. S. 132, 142 (1963), our analysis has included “due regard for the presuppositions of our embracing federal system, including the principle of diffusion of power not as a matter of doctrinaire localism but as a promoter of democracy.” San Diego Building Trades Council v. Garmon, 359 U. S. 236, 243 (1959). Such concerns are not implicated in the same fashion when the question is whether federal statutory or federal common law governs, and accordingly the same sort of evidence of a clear and manifest purpose is not required. Indeed, as noted, in cases such as the present “we start with the assumption” that it is for Congress, not federal courts, to articulate the appropriate standards to be applied as a matter of federal law.
Ill
We conclude that, at least so far as concerns the claims of respondents, Congress has not left the formulation of appropriate federal standards to the courts through application of often vague and indeterminate nuisance concepts and maxims of equity jurisprudence, but rather has occupied the field through the establishment of a comprehensive regulatory program supervised by an expert administrative agency. The 1972 Amendments to the Federal Water Pollution Control Act were not merely another law “touching interstate waters” of the sort surveyed in Illinois v. Milwaukee, 406 U. S., at 101-103, and found inadequate to supplant federal common law. Rather, the Amendments were viewed by Congress as a “total restructuring” and “complete rewriting” of the existing water pollution legislation considered in that case. 1 Leg. Hist. 350-351 (remarks of Chairman Blatnik of the House Committee which drafted the House version of the Amendments) ; id., at 359-360 (remarks of Rep. Jones). See S. Rep. No. 92-414, p. 95 (.1971), 2 Leg. Hist. 1511; id., at 1271 (remarks of Chairman Randolph of the Senate Committee which drafted the Senate version of the Amendments); see also EPA v. State Water Resources Control Board, 426 U. S., at 202-203. Congress’ intent in enacting the Amendments was clearly to establish an all-encompassing program of water pollution regulation. Every point source discharge is prohibited unless covered by a permit, which directly subjects the discharger to the administrative apparatus established by Congress to achieve its goals. The “major purpose” of the Amendments was “to establish a comprehensive long-range policy for the elimination of water pollution.” S. Rep. No. 92-414, at 95, 2 Leg. Hist. 1511 (emphasis supplied). No Congressman’s remarks on the legislation were complete without reference to the “comprehensive” nature of the Amendments. A House sponsor described the bill as “the most comprehensive and far-reaching water pollution bill we have ever drafted,” 1 Leg. Hist. 369 (Rep. Mizell), and Senator Randolph, Chairman of the responsible Committee in the Senate, stated: “It is perhaps the most comprehensive legislation ever developed in its field. It is perhaps the most comprehensive legislation that the Congress of the United States has ever developed in this particular field of the environment.” 2 id., at 1269. This Court was obviously correct when it described the 1972 Amendments as establishing “a comprehensive program for controlling and abating water pollution.” Train v. City of New York, 420 U. S. 35, 37 (1975). The establishment of such a self-consciously comprehensive program by Congress, which certainly did not exist when Illinois v. Milwaukee was decided, strongly suggests that there is no room for courts to attempt to improve on that program with federal common law. See Texas v. Pankey, 441 F. 2d, at 241.
Turning to the particular claims involved in this case, the action of Congress in supplanting the federal common law is perhaps clearest when the question of effluent limitations for discharges from the two treatment plants is considered. The duly issued permits under which the city Commission discharges treated sewage from the Jones Island and South Shore treatment plants incorporate, as required by the Act, see § 402 (b)(1), 33 U. S. C. § 1342 (b)(1) (1976 ed. and Supp. Ill), the specific effluent limitations established by EPA regulations pursuant to § 301 of the Act, 33 U. S. C. § 1311 (1976 ed. and Supp. III). App. 371-394, 395-424; see 40 CFR § 133.102 (1980). There is thus no question that the problem of effluent limitations has been thoroughly addressed through the administrative scheme established by Congress, as contemplated by Congress. This being so there is no basis for a federal court to impose more stringent limitations than those imposed under the regulatory regime by reference to federal common law, as the District Court did in this case. The Court of Appeals, we believe, also erred in stating:
“Neither the minimum effluent limitations prescribed by EPA pursuant to the provisions of the Act nor the effluent limitations imposed by the Wisconsin agency under the National Pollutant Discharge Elimination System limit a federal court’s authority to require compliance with more stringent limitations under the federal common law.” 599 F. 2d, at 173.
Federal courts lack authority to impose more stringent effluent limitations under federal common law than those imposed by the agency charged by Congress with administering this comprehensive scheme.
The overflows do not present a different case. They are point source discharges and, under the Act, are prohibited unless subject to a duly issued permit. As with the discharge of treated sewage, the overflows, through the permit procedure of the Act, are referred to expert administrative agencies for control. All three of the permits issued to petitioners explicitly address the problem of overflows. The Jones Island and South Shore permits, in addition to covering discharges from the treatment plants, also cover overflows from various lines leading to the plants. As issued on December 24, 1974, these permits require the city Commission “to initiate a program leading to the elimination or control of all discharge overflow and/or bypass points in the [Jones Island or South Shore, respectively] Collector System ... to assure attainment of all applicable Water Quality Standards.” App. 378-379, 416. The specific discharge points are identified. The Commission was required to submit a detailed plan to DNR designed to achieve these objectives, including alternative engineering solutions and cost estimates, file a report on an attached form for all overflows that do occur, install monitoring devices on selected overflows discharge points, and file more detailed quarterly reports on the overflows from those points. The Commission was also required to complete “facilities planning” for the combined sewer area. “The facilities planning elements include a feasibility study, cost-effectiveness analysis and environmental assessment for elimination or control of the discharges from the combined sewers.” Quarterly progress reports on this planning are required. Id., at 379. A permit issued to the city on December 18, 1974, covers discharges “from sanitary sewer crossovers, combined sewer crossovers and combined sewer overflows.” Id., at 425. Again the discharge points are specifically identified. As to separated sewers, the city “is required to initiate a program leading to the elimination of the sanitary sewer crossovers (gravity) and the electrically operated relief pumps . . . .” Id., at 438. A detailed plan to achieve this objective must be submitted, again with alternative engineering solutions and cost estimates, any overflows must be reported to DNR on a specified form, and monitoring devices are required to be installed on selected points to provide more detailed quarterly reports. As to the combined sewers, the city “is required to initiate a program leading to the attainment of control of overflows from the city’s combined sewer system . . . .” Id., at 443. The city is required to cooperate with and assist the city Commission in facilities planning for combined sewers, see supra, this page, submit quarterly progress reports to DNR, file reports on all discharges, and install monitoring devices on selected discharge points to provide more detailed quarterly reports “until the discharges are eliminated or controlled.” App. 444.
The enforcement action brought by the DNR in state court resulted in a judgment requiring “ [elimination of any bypassing or overflowing which occurs within the sewerage systems under dry weather by not later than July 1, 1982.” Id., at 465. Wet weather overflows from separated sewers were to be subject to a coordinated effort by the Commissions resulting in correction of the problem by July 1, 1986, pursuant to a plan submitted to the DNR. Id., at 469-471. As to the combined sewer overflows, the Commissions were required to accomplish an abatement project, with design work completed by July 1, 1981, and construction by July 1, 1993. Annual progress reports were required to be submitted to the DNR. Id., at 471-472.
It is quite clear from the foregoing that the state agency duly authorized by the EPA to issue discharge permits under ^the Act has addressed the problem of overflows from petitioners’ sewer system. The agency imposed the conditions it considered best suited to further the goals of the Act, and provided for detailed progress reports so that it could continually monitor the situation. Enforcement action considered appropriate by the state agency was brought, as contemplated by the Act, again specifically addressed to the overflow problem. There is no “interstice” here to be filled by federal common law: overflows are covered by the Act and have been addressed by the regulatory regime established by the Act. Although a federal court may disagree with the regulatory approach taken by the agency with responsibility for issuing permits under the Act, such disagreement alone is no basis for the creation of federal common law.
Respondents strenuously argue that federal common law continues to be available, stressing that neither in the permits nor the enforcement order are there any effluent limitations on overflows. This argument, we think, is something of a red herring. The difference in treatment between overflows and treated effluent by the agencies is due to differences in the nature of the problems, not the extent to which the problems have been addressed. The relevant question with overflow discharges is not, as with discharges of treated sewage, what concentration of various pollutants will be permitted. Rather the question is what degree of control will be required in preventing overflows and ensuring that the sewage undergoes treatment. This question is answered by construction plans designed to accommodate a certain amount of sewage that would otherwise be discharged on overflow occasions. The EPA has not promulgated regulations mandating specific control guidelines because of a recognition that the problem is “site specific.” See, e. g., EPA Program Requirements Memorandum PRM No. 75-34 (Dec. 16, 1975):
“The costs and benefits of control of various portions of pollution due to combined sewer overflows and bypasses vary greatly with the characteristics of the sewer and treatment system, the duration, intensity, frequency, and aerial extent of precipitation, the type and extent of development in the service area, and the characteristics, uses and water quality standards of the receiving waters. Decisions on grants for control of combined sewer overflows, therefore, must be made on a case-by-case basis after detailed planning at the local level.”
See also EPA, Report to Congress on Control of Combined Sewer Overflow in the United States 7-1, 7-13 (MCD-50, 1978). Decision is made on a case-by-case basis, through the permit procedure, as was. done here. Demanding specific regulations of general applicability before concluding that Congress has addressed the problem to the exclusion of federal common law asks the wrong question. The question is whether the field has been occupied, not whether it has been occupied in a particular manner.
The invocation of federal common law by the District Court and the Court of Appeals in the face of congressional legislation supplanting it is peculiarly inappropriate in areas as complex as water pollution control. As the District Court noted:
“It is well known to all of us that the arcane subject matter of some of the expert testimony in this case was sometimes over the heads of all of us to one height or another. I would certainly be less than candid if I did not acknowledge that my grasp of some of the testimony was less complete than I would like it to be . . . .” App. to Pet. for Cert. P-4.
Not only are the technical problems difficult — doubtless the reason Congress vested authority to administer the Act in administrative agencies possessing the necessary expertise— but the general area is particularly unsuited to the approach inevitable under a regime of federal common law. Congress criticized past approaches to water pollution control as being “sporadic” and “ad hoc,” S. Rep. No. 92-414, p. 95 (1971), 2 Leg. Hist. 1511, apt characterizations of any judicial approach applying federal common law, see Wilburn Boat Co. v. Fireman’s Fund Ins. Co., 348 U. S. 310, 319 (1955).
It is also significant that Congress addressed in the 1972 Amendments one of the major concerns underlying the recognition of federal common law in Illinois v. Milwaukee. We were concerned in that ease that Illinois did not have any forum in which to protect its interests unless federal common law were created. See 406 U. S., at 104, 107. In the 1972 Amendments Congress provided ample opportunity for a State affected by decisions of a neighboring State’s permit-granting agency to seek redress. Under §402 (b)(3), 33 U. S. C. § 1342 (b)(3), a state permit-granting agency must ensure that any State whose waters may be affected by the issuance of a permit receives notice of the permit application and the opportunity to participate in a public hearing. Wisconsin law accordingly guarantees such notice and hearing, see Wis. Stat. Ann. §§ 147.11, 147.13 (West Supp. 1980-1981). Respondents received notice of each of the permits involved here, and public hearings were held, but they did not participate in them in any way. Section 402 (b) (5), 33 U. S. C. § 1342 (b) (5), provides that state permit-granting agencies must ensure that affected States have an opportunity to submit written recommendations concerning the permit applications to the issuing State and the EPA, and both the affected State and the EPA must receive notice and a statement of reasons if any part of the recommendations of the affected State are not accepted. Again respondents did not avail themselves of this statutory opportunity. Under § 402 (d) (2) (A), 33 U. S. C. § 1342 (d)(2)(A) (1976 ed., Supp. Ill), the EPA may veto any permit issued by a State when waters of another State may be affected. Respondents did not request such action. Under § 402 (d) (4) of the Act, 33 U. S. C. § 1342 (d) (4) (1976 ed., Supp. Ill), added in .1977, the EPA itself may issue permits if a stalemate between an issuing and objecting State develops. The basic grievance of respondents is that the permits issued to petitioners pursuant to the Act do not impose stringent enough controls on petitioners’ discharges. The statutory scheme established by Congress provides a forum for the pursuit of such claims before expert agencies by means of the permit-granting process. It would be quite inconsistent with this scheme if federal courts were in effect to “write their own ticket” under the guise of federal common law after permits have already been issued and permittees have been planning and operating in reliance on them.
Respondents argue that congressional intent to preserve the federal common-law remedy recognized in Illinois v. Milwaukee is evident in §§ 510 and 505 (e) of the statute, 33 U. S. C. §§ 1370, 1365 (e). Section 510 provides that nothing in the Act shall preclude States from adopting and enforcing limitations on the discharge of pollutants more stringent than those adopted under the Act. It is one thing, however, to say that States may adopt more stringent limitations through state administrative processes, or even that States may establish such limitations through state nuisance law, and apply them to in-state dischargers. It is quite another to say that the States may call upon federal courts to employ federal common law to establish more stringent standards applicable to out-of-state dischargers. Any standards established under federal common law are federal standards, and so the authority of States to impose more stringent standards under § 510 would not seem relevant. Section 510 clearly contemplates state authority to establish more stringent pollution limitations; nothing in it, however, suggests that this was to be done by federal-court actions premised on federal common law.
Subsection 505 (e) provides:
“Nothing in this section shall restrict any right which any person (or class of persons) may have under any statute or common law to seek enforcement of any effluent standard or limitation or to seek any other relief (including relief against the Administrator or a State agency)” (emphasis supplied).
Respondents argue that this evinces an intent to preserve the federal common law of nuisance. We, however, are inclined to view the quoted provision as meaning what it says: that nothing in § 505, the citizen-suit provision, should be read as limiting any other remedies which might exist.
Subsection 505 (e) is virtually identical to subsections in the citizen-suit provisions of several environmental statutes. The subsection is common language accompanying citizen-suit provisions and we think that it means only that the provision of such suit does not revoke other remedies. It most assuredly cannot be read to mean that the Act as a whole does not supplant formerly available federal common-law actions but only that the particular section authorizing citizen suits does not do so. No one, however, maintains that the citizen-suit provision pre-empts federal common law.
We are thus not persuaded that § 505 (e) aids respondents in this case, even indulging the unlikely assumption that the reference to “common law” in § 505 (e) includes the limited federal common law as opposed to the more routine state common law. See Committee for Consideration of Jones Falls Sewage System v. Train, 539 F. 2d, at 1009, n. 9.
The dissent considers “particularly revealing,” post, at 343, a colloquy involving Senators Griffin, Muskie, and Hart, concerning the pendency of an action by the EPA against Reserve Mining Co. Senator Griffin expressed concern that “one provision in the conference agreement might adversely affect a number of pending lawsuits brought under the Refuse Act of 1899,” including the Reserve Mining litigation. 1 Leg. Hist. 190. The provision which concerned Senator Griffin, enacted as § 402 (k), 86 Stat. 883, 33 U. S. C. § 1342 (k), provides, in pertinent part:
“Until December 31, 1974, in any case where a permit for discharge has been applied for pursuant to this section, but final administrative disposition of such application has not been made, such discharge shall not be a violation of (1) section 301, 306, or 402 of this Act, or (2) section 13 of the Act of March 3, 1899, unless the Administrator or other plaintiff proves that final administrative disposition of such application has not been made because of the failure of the applicant to furnish information reasonably required or requested in order to process the application.”
Senator Griffin was concerned about the relation between this provision and § 4 (a) of the bill, which provided that “[n]o suit, action or other proceeding lawfully commenced by or against the Administrator or any other officer or employee of the United States in his official capacity or in relation to the discharge of his official duties under the Federal Water Pollution Control Act as in effect immediately prior to the date of enactment of the Act shall abate by reason of the taking effect of the amendment made by section 2 of this Act.” Senator Griffin stated that “when these provisions are read together, it is not altogether clear what effect is intended with respect to pending Federal court suits against polluters violating the Refuse Act of 1899.”
Senator Muskie responded to Senator Griffin’s concerns by quoting § 4 («•) and stating that “[w]ithout any question it was the intent of the conferees that this provision include enforcement actions brought under the Refuse Act, the Federal Water Pollution Control Act, and any other acts of Congress.” 1 Leg. Hist. 193. Later Senator Hart stated: “It is my understanding, . . . after the explanation of the Senator from Maine, that the suit now pending against the Reserve Mining Co., under the Refuse Act of 1899 will in no way be affected nor will any of the other counts under the existing Federal Water Pollution Control Act or other law.” Id., at 211. When Senator Muskie’s and Hart’s remarks are viewed in this context it is clear that they do not bear on the issue now before the Court. In the first place, although there was a federal common-law claim in the Reserve Mining litigation, Senator Griffin focused on the Refuse Act of 1899— not federal common law. Senator Muskie, with his reference to “other acts of Congress,” rather clearly was not discussing federal common law. Most importantly, however, Senator Muskie based his response to Senator Griffin — that the Re^ serve Mining suit would not be affected — on a specific section of the bill, § 4 (a), which is not applicable to suits other than those brought by or against the Federal Government and pending when the Amendments were enacted. Senator Hart based his response on the explanation given by Senator Muskie. Even if we assumed that the legislators were focusing on the federal common-law aspects of the Reserve Mining litigation (and we do not think they were), Senators Muskie and Hart informed Senator Griffin that the Reserve Mining suit was not affected because of § 4 (a), and not at all because the Act did not displace the federal common law of nuisance. Senator Griffin’s question focused on § 4 (a); understandably, so did the assurances he received. Nothing about the colloquy suggests any intent concerning the continued validity of federal common law. The issue simply did not come up because Senator Griffin’s concerns were fully answered by a particular section not applicable in the case before us.
We therefore conclude that no federal common-law remedy was available to respondents in this case. The judgment of the Court of Appeals is therefore vacated, and the case is remanded for proceedings consistent with this opinion.
It is so ordered.
It is the statutory responsibility of the city Commission to “project, plan, construct, maintain and establish a sewerage system for the collection, transmission, and disposal of all sewage and drainage of the city.” Wis. Stat. Ann. §62.61 (1) (West Supp. 1980-1981). The city Commission is specifically given the authority to “plan, construct, and establish all local, district, lateral, intercepting, outfall or other sewers, and all conduits, drains and pumping or other plants, and all buildings, structures, works, apparatus, or agencies, and to lay all mains and pipes, and to create or use all such instrumentalities and means ... as it deems expedient or necessary for carrying the sewerage system . . . into full effect.” § 62.61 (l)(d). The county Commission is responsible for the construction of sewers within the metropolitan area but outside city limits. § 59.96 (6) (a). The city operates some sewers within the city, although the powers of the city Commission include the use and alteration, in its discretion, of “any or all existing public sewers or drains, including storm-water sewers and drains, in the city.” § 62.61 (1) (e). Any construction by the city of local or sanitary sewers is subject to the prior written approval of the city Commission. § 62.67.
Combined sewers are obviously more susceptible to overflows after storms because the storm water is transported in the same conduits as the sewage. Since ground water and water from storm sewers occasionally enter separated sewers, overflows in those systems are also more likely during wet weather. When the system is about to exceed its inherent capacity at given points, overflow devices, either mechanical or gravity, are activated, resulting in the discharge of the effluent. See 599 E. 2d 151, 167-168.
Eutrophication is the natural process by which the nutrient concentration in a body of water gradually increases. The process is allegedly accelerated when nutrients in sewage, particularly phosphorus, are discharged into the water. See id.., at 169, n. 39.
The complaint also sought relief, in counts II and III, under Illinois statutory and common law. See App. 29-32. The District Court stated that “the case should be decided under the principles of the federal common law of nuisance,” App. to Pet. for Cert. F-2, but went on to find liability on all three counts of the complaint, id., at F-24. The Court of Appeals ruled that “it is federal common law and not state statutory or common law that controls in this ease, Illinois v. Milwaukee, supra, 406 U. S., at 107, & n. 9, . . . and therefore we do not address the state law claims.” 599 F. 2d, at 177, n. 53. Although respondent Illinois argues this point in its brief, the issue before us is simply whether federal legislation has supplanted federal common law. The question whether state law is also available is the subject of Illinois’ petition for certiorari, No. 79-571.
The Court of Appeals also rejected petitioners' contentions that there was no in personam jurisdiction under the Illinois long-arm statute, that any exercise of in personam jurisdiction failed to meet the minimum-contacts test of International Shoe Co. v. Washington, 326 U. S. 310 (1945), and that venue was improper. 599 F. 2d, at 155-157. We agree that, given the existence of a federal common-law claim at 'the commencement of the suit, prior to the enactment of the 1972 Amendments, personal jurisdiction was properly exercised and venue was also proper.
See Hart, The Relations Between State and Federal Law, 54 Colum. L. Rev. 489, 497 (1954) (“[f]ederal intervention has been thought of as requiring special justification, and the decision that such justification has been shown, being essentially discretionary, has belonged in most cases to Congress”) (footnote omitted).
In this regard we note the inconsistency in Illinois’ argument and the decision of the District Court that both federal and state nuisance law apply to this case. If state law can be applied, there is no need for federal common law; if federal common law exists, it is because state law cannot be used.
The dissent errs in labeling our approach “automatic displacement,” post, at 334. As evident infra, at 317-323, the question whether a previously available federal common-law action has been displaced by federal statutory law involves an assessment of the scope of the legislation and whether the scheme established by Congress addresses the problem formerly governed by federal common law. Our “detailed review of respondents’ claims,” post, at 348, is such an assessment and not, as the dissent suggests, a consideration of whether the particular common law applied below was reasonable.
The dissent’s reference to “the unique role federal common law plays in resolving disputes between one State and the citizens or government of another,” post, at 334, does not advance its argument. Whether interstate in nature or not, if a dispute implicates “Commerce . . . among the several States” Congress is authorized to enact the substantive federal law governing the dispute. Although the Court has formulated “interstate common law,” Kansas v. Colorado, 206 U. S. 46, 98 (1907), it has done so not because the usual separation-of-powers principles do not apply, but rather because interstate disputes frequently call for the application of a federal rule when Congress has not spoken. When Congress has spoken its decision controls, even in the context of interstate disputes. See Arizona v. California, 373 U. S. 546 (1963).
Since the States are represented in Congress but not in the federal courts, the very concerns about displacing state law which counsel against, finding pre-emption of state law in the absence of clear intent actually suggest a willingness to find congressional displacement of federal common law. Simply because the opinion in Illinois v. Milwaukee used the term “pre-emption,” usually employed in determining if federal law 'displaces! state law, is no reason to assume the analysis used to decide the usual,' federal-state questions is appropriate here.
The dissent considers the Water Pollution Control Act of 1948 “broad and systematic,” post, at 338, and emphasizes that the Court in Illinois v. Milwaukee did not view then-existing federal statutes as a barrier to the recognition of federal common law, post, at 337. The suggestion is that the present legislation similarly should be no barrier. This ignores Congress’ view that the previous legislation was “inadequate in every vital aspect,” 2 Leg. Hist. 1425, and Congress’ clear intent, witnessed by the statements and citations in the text, to do something quite different with the 1972 Amendments.
“Point source” is defined in § 502 (14) of the Act, 33 U. S. C. § 1362 (14) (1976 ed., Supp. Ill), as “any discernible, confined and discrete conveyance . . . from which pollutants are or may be discharged.” There is no question that all of the discharges involved in this case are point source discharges.
The most casual perusal of the legislative history demonstrates that these views on the comprehensive nature of the legislation were practically universal. See, e. g., 1 Leg. Hist. 343 (Rep. Young); id., at 350 (Rep. Blatnik); id., at 374 (Rep. Clausen); id., at 380 (Rep. Roberts); id., at 425 (Rep. Roe); id., at 450 (Rep. Reuss); id., at 467 (Rep. Dingell); id., at 481 (Rep. Caffery); 2 id., at 1302 (Sen. Cooper); id., at 1408 (Sen. Hart).
The Court of Appeals itself recognized that Congress in the 1972 Amendments “established a comprehensive and detailed system for the regulation and eventual elimination of pollutant discharges into the nation’s waters.” 599 F. 2d, at 162.
This conclusion is not undermined by Congress’ decision to permit States to establish more stringent standards, see § 510, 33 U. S. C. § 1370. While Congress recognized a role for the States, the comprehensive nature of its action suggests that it was the exclusive source of federal law. Cases recognizing that the comprehensive character of a federal program is an insufficient basis to find pre-emption of state law are not in point, since we are considering which branch of the Fedéral Government is the source of federal law, not whether that law pre-empts state law, see supra, at 316-317. Since federal courts create federal common law only as a necessary expedient when problems requiring federal answers are not addressed by federal statutory law, see supra, at 312-315, the comprehensive character of a federal statute is quite relevant to the present question, while it would not be were the question whether state law, which of course does not depend upon the absence of an applicable Act of Congress, still applied.
The regulatory approach of the DNR to overflows reflected in these permit conditions was not plucked out of thin air but rather followed the approach in EPA regulations, issued pursuant to the Act, governing the availability of federal funds for treatment works construction, including construction of facilities to control sewer overflows. The regulations provide, as do the permits, for detailed evaluation of feasibility, engineering alternatives, and costs prior to the commencement of a particular construction project. See 40 CFR §§35.903, 35.917 (1980). The “facilities planning” referred to in the permits for control of combined sewer overflows is a term of art defined in exhaustive detail in the EPA regulations, see §§ 35.917-35.917-9. Such facilities planning constitutes the first step in qualifying for federal financial assistance for construction projects. It was the statutorily articulated intent of Congress to make funds available, subject to certain conditions, for projects to control overflows, see §§ 201 (g)(1), 212 (2) (A), (B), 33'U. S. C. §§ 1281 (g) (1), 1292 (2) (A), (B) (1976 ed. and Supp. Ill); see also S. Rep. No. 92-414, pp. 40-41 (1971), 2 Leg. Hist. 1458-1459; 1 id., at 165 (Sen. Muskie); 2 id., at 1379 (Sen. Magnuson). We are not impressed with arguments that more in the way of immediate solutions should have been required of the dischargers when such requirements may have had the effect, under EPA regulations requiring exhaustive planning and examination of alternatives, of foreclosing recourse to funds Congress intended to be available.
In light of this conclusion we need not consider petitioners’ argument that, assuming the availability of a cause of action, the lower courts erred in concluding that respondents’ evidence sufficed to establish the existence of a nuisance.
See EPA, Benefit Analysis for Combined Sewer Overflow Control 4 (1979) (“regulations governing combined sewer overflows require permits for each outfall . . . they differ from the . . . permits for treatment plants, which specify effluent limitations based on technology or water quality standards. NPDES permits for combined sewer overflows contain no effluent limitations, though they do usually require monitoring and data collection”).
The point is perhaps made most clear if one asks what inadequacy in the treatment by Congress the courts below rectified through creation of federal common law. In imposing stricter effluent limitations the District Court was not “filling a gap” in the regulatory scheme, it was simply providing a different regulatory scheme. The same is true with overflows. The District Court simply ordered planning and construction designed to achieve more stringent control of overflows than the planning and construction undertaken pursuant to the permits. The same point is evident in examining respondents’ arguments. The basic complaint is that the permits issued to petitioners under the Act do not control overflows or treated discharges in a sufficiently stringent manner, not that permits under the Act cannot deal with these subjects or that the instant permits do not do so. At most respondents argue not that the Act is inadequate, as was the legislation considered in Illinois v. Milwaukee, but that these particular permits issued under it are. This does not suffice to create an “interstice” to be filled by federal common law.
It must be noted that the legislative activity resulting in the 19-72 Amendments largely occurred prior to this Court’s decision in Illinois v. Milwaukee. Drafting, filing of Committee Reports, and debate in both Houses took place prior to the decision. Only conference activity occurred after. It is therefore difficult to argue that particular provisions were designed to preserve a federal common-law remedy not yet recognized by this Court.
The dissent cites several cases for the proposition that the federal common-law nuisance remedy existed “[l]ong before” Illinois v. Milwaukee. Post, at 335. During the legislative activity resulting in the 1972 Amendments, however, this Court’s decision in Ohio v. Wyandotte Chemicals Corp., 401 U. S. 493 (1971), indicated that state common law would control a claim such as Illinois’. Wyandotte, like the present suit, was brought by a State to abate a pollution nuisance created by out-of-state defendants. The Court ruled that “an action such as this, if otherwise cognizable in federal district court, would have to be adjudicated under state law. Erie R. Co. v. Tompkins, 304 U. S. 64 (1938).” Id., at 498-499, n. 3. The Court in Illinois v. Milwaukee found it necessary to overrule this statement, see 406 U. S., at 102, n. 3.
In full, § 510, as set forth in 33 U. S. C. § 1370, provides:
“Except as expressly provided in this chapter, nothing in this chapter shall (1) preclude or deny the right of any State or political subdivision thereof or interstate agency to adopt or enforce (A) any standard or limitation respecting discharges of pollutants, or (B) any requirement respecting control or abatement of pollution; except that if any effluent limitation, or other limitation, effluent standard, prohibition, pretreatment standard, or standard of performance is in effect under this chapter, such State or political subdivision or interstate agency may not adopt or enforce any effluent limitation, or other limitation, effluent standard, prohibition, pretreatment standard, or standard of performance which is less stringent than the effluent limitation, or other limitation, effluent standard, prohibition, pretreatment standard, or standard of performance under this chapter; or (2) be construed as impairing or in any manner affecting any right or jurisdiction of the States with respect to the waters (including boundary waters) of such States.”
See, e. g., § 304 (e) of the Clean Air Act, 42 U. S. C. § 7604 (e) (1976 ed., Supp. III); § 16 (e) of the Deepwater Port Act of 1974, 33 U. S. C. § 1515 (e); § 105 (g) (5) of the Marine Protection, Research, and Sanctuaries Act of 1972, 33 U. S. C. § 1415 (g) (5); § 12 (e) of the Noise Control Act of 1972, 42 U. S. C. § 4911 (e); § 7002 (f) of the Solid Waste Disposal Act, 42 17. S. C. § 6972 (f); § 1449 (e) of the Safe Drinking Water Act, 42 U. S. C. § 300j — 8 (e) (1976 ed., Supp. III); § 520 (e) of the Surface Mining Control and Reclamation Act of 1977, 30 U. S. C. § 1270 (e) (1976 ed., Supp. III); and § 20 (c) (3) of the Toxic Substances Control Act, 15 U. S. C. §2619 (c)(3).
The dissent’s criticism of our reading of § 505 (e), post, at 341-342, is misplaced. There is nothing unusual about Congress enacting a particular provision, and taking care that this enactment by itself not disturb other remedies, without considering whether the rest of the Act does so or what other remedies may be available. The fact that the language of § 505 (e) is repeated in haec verba in the citizen-suit provisions of a vast array of environmental legislation, see n. 21, supra, indicates that it does not reflect any considered judgment about what other remedies were previously available or continue to be available under any particular statute. The dissent refers to our reading as “extremely strained,” but the dissent, in relying on § 505 (e) as evidence of Congress’ intent to preserve the federal common-law nuisance remedy, must read “nothing in this section” to mean “nothing in this Act.” We prefer to read the statute as written. Congress knows how to say “nothing in this Act” when it means to, see, e. g., Pub. L. 96-510, § 114 (a), 94 Stat. 2795.
The dissent states that “Senators Muskie and Hart each responded” as Senator Hart is quoted in the text. Post, at 344. This is not strictly accurate. Senator Muskie never responded as Senator Hart did, but rather as quoted in the text above, with the clear reference to § 4 (a). He did not, like Senator Hart, use the phrase “other law” but rather, and of particular significance in the present context, the phrase “any other acts of Congress." This inaccuracy in the dissent appears to be of no little importance, since the dissent attaches great weight to the views of Senator Muskie, see post, at 344, n. 16.
In the similar colloquy in the House, also relied upon by the dissent, Representative Wright responded to a question from Representative Dingell in precisely the same manner as Senator Muskie responded to Senator Griffin, relying on §4 (a), and referring to “other acts of Congress.” 1 Leg. Hist. 248. Representative Dingell never mentioned federal common law in his question.
The dissent also relies on the failure of Congress to enact, in 1977, an amendment “proposed” by Representative Aspin. Post, at 345-346. This reliance ignores not only the fact that “unsuccessful attempts at legislation are not the best of guides to legislative intent,” Bed Lion Broadcasting Co. v. FCC, 395 U. S. 367, 381-382, n. 11 (1969), but also, even assuming the failure to enact the Aspin “proposal” is some indication of Congress’ intent in 1977, the “oft-repeated warning” that “the views of a subsequent Congress form a hazardous basis for inferring the intent of an earlier one.” Consumer Product Safety Comm’n v. GTE Sylvania, Inc., 447 U. S. 102, 117-118 (1980). These admonitions do not even come into play, however, since the Aspin proposal was never introduced in either House of Congress; it does not even appear in the Congressional Record. The fate of the Aspin “proposal” has under our precedents dealing with statutory interpretation nothing whatever to do with Congress’ intent concerning federal common law when it enacted the 1972 Amendments.