This is an appeal from a preliminary injunction which enjoined construction of the Libby Additional Units and Reregulation Dam (hereinafter LAURD) on the Kootenai River in Montana.1
The project was authorized by the Flood Control Act of 1950 (the Act), Pub.L. 516, 64 Stat. 170 (May 17, 1950). Construction began on the main dam in 1966, and was completed in 1973. The Act authorized ten generators for the Libby Dam. Four were installed originally in the dam, and the Corps of Engineers (the Corps) intends to add four more as part of the LAURD project.
The additional units cannot be fully utilized without the construction of a reregulating dam downstream to modify river fluctuations resulting from the release of water from the main dam. The Corps, on the assumption that the 1950 Flood Control Act authorized a reregulating dam as well as the main Libby Dam, developed plans for building the reregulating facility. Funds were requested and Congress appropriated money specifically for the reregulating dam.
An Environmental Impact Statement (EIS), fashioned as a final supplement to the impact statement written for the main Libby Dam, was prepared in 1974. Apparently no objections were expressed when the draft EIS was circulated prior to the adoption of the final EIS..
Plaintiffs-Appellees Libby Rod and Gun Club, Montana Wildlife Federation, and Montana Wilderness Association (hereinafter Rod and Gun Club) sued in the district court, for a preliminary injunction enjoining construction of the reregulating facility. The Rod and Gun Club argued that the Corps: (1) violated 33 U.S.C. § 401 by proceeding with construction of the reregulating dam without Congressional approval; (2) violated the Endangered Species Act of 1973, 16 U.S.C. § 1531 et seq.; (3) failed to conduct a valid cost-benefit analysis of the project as required by the Flood Control Act of 1936, 33 U.S.C. §§ 701-09a; (4) violated the National Environmental Policy Act of 1969 (NEPA), 42 U.S.C. § 4331 et seq.; and (5) failed to comply with the National Historic Preservation Act of 1966, 16 U.S.C. §§ 470-470t.
The district court entered a preliminary injunction enjoining all construction on the LAURD project, including the addition of generators to the main Libby Dam. The court based its ruling on two grounds: (1) that the Rod and Gun Club would prevail because Congress had not authorized the LAURD project; and (2) that the Rod and *744Gun Club similarly had demonstrated that the Corps had not complied with NEPA, in that it had failed adequately to consider alternatives to the LAURD project.
The Corps appealed and moved for a stay of the injunction pending appeal. A motions panel of this court denied the motion, but allowed the Corps to continue expansion on the main Libby Dam pending appeal.
I.
AUTHORIZATION
Although this is an appeal from the granting of a preliminary injunction, the parties suggest that, because no further evidence is to be presented on the authorization question, the district court’s holding on that issue should be treated as a final decision. We conclude that the public interest can be served best by reviewing this aspect of the case as an appeal on the merits.
Congressional authorization is required before a dam may be constructed on a navigable river. 33 U.S.C. § 401 (1976). Section 401 provides in relevant part:
It shall not be lawful to construct or commence the construction of any bridge, dam, dike, or causeway over or in any . navigable river . . until the consent of Congress to the building of such structures shall have been obtained
The section has been interpreted to apply to federal dam construction projects. United States v. Arizona, 295 U.S. 174, 183-84, 55 S.Ct. 666, 79 L.Ed. 1371 (1935); Atchison, Topeka and Santa Fe Railway Co. v. Callaway, 382 F.Supp. 610, 616 (D.D.C.1974), vacated 431 F.Supp. 722 (D.D.C.1977).2
A. THE FLOOD CONTROL ACT OF 1950.
The Corps contends that the Act of 1950, which authorized the construction of the main Libby Dam, also authorized a reregulating dam. The Act contains no reference to a reregulation facility. It does incorporate by reference H.R.Doc.No.531, 81st Cong., 2d Sess. (1950), which sets forth the Corps’ recommended plans for construction of the Libby Dam. Paragraph 165 of the document states:
165. Reregulation. — A sudden increase of flow from no load at minimum release to full load would raise the river stage at the dam about 15 feet. This sudden rise in stage partly would be absorbed by channel storage, decreasing in amount as its front traveled downstream. It is estimated that the maximum rise would amount to about 5 feet at the city of Libby, less than 3 feet at Troy, and less than 2 feet at Bonners Ferry. Just what effect this stage variation might have along the river is unknown at this time. However, the probable operation of the Libby generating station calls for this wide variation of load very seldom. If it becomes necessary to reduce this fluctuation, reregulation will be considered when the need arises.
(Emphasis added.)
The Corps argues that because 1| 165 placed Congress on notice of the possible need for a reregulating dam if additional turbines were placed in the main Libby Dam, the authorization of the general Libby Dam project contained in the Flood Control Act included explicit authorization of a reregulating facility.
We do not read H 165 to support the conclusion that Congress intended explicitly to authorize a reregulating dam. To the contrary, the paragraph indicates that the need *745for a reregulating facility was unclear when the main Libby Dam was authorized, and that the necessity of such a reregulating facility was to be evaluated if and when “the need arises.”3 We agree with the district court that such tentative reference to reregulation cannot be construed as explicit authorization of a reregulating dam.
The Corps further argues that, even if the Flood Control Act cannot be read explicitly to authorize a reregulating dam, it nonetheless authorized the addition of turbines to the main Libby Dam. Because these additional turbines cannot be fully utilized without a second dam, the Corps contends that by authorizing them Congress necessarily authorized the reregulation dam by implication.
We decline to adopt this proposition for two reasons. First, § 401 mandates that the consent of Congress be obtained before beginning construction of a dam. Assuming arguendo that certain aspects of the Libby Dam project not specifically referred to by Congress in the Flood Control Act may have been authorized by implication because they are necessary to the effective functioning of the main Libby Dam, we cannot extend such implied authorization to a second dam in light of the requirement that Congress explicitly authorize dam projects. The Corps fails to present this court with applicable authority to support the view that the necessity of a dam will allow a court to infer its authorization, and we feel constrained in this case to follow the clearer dictates of § 401.
Second, the very language of 1165 militates against implying authorization of a second dam. As we have noted, that paragraph indicates that the need for reregulation was uncertain when Congress passed the Flood Control Act, and that the necessity of a reregulation facility would be examined “when the need arises.’’ To conclude that a reregulating dam was authorized by necessity would frustrate the congressional intent to examine the need for a reregulating dam expressed in 1165.
We therefore reject the Corps’ first argument that the Flood Control Act of 1950 authorized the reregulating dam, either explicitly or by implication.
B. CONGRESSIONAL APPROPRIATIONS AND AUTHORIZATION.
Congress has on a number of occasions appropriated funds specifically for the construction of the reregulating dam.4 The Corps contends that such appropriations are equivalent to authorization of the second dam. The Rod and Gun Club conversely argues, and the district court agreed, that the recent Supreme Court ruling in T. V. A. v. Hill, 437 U.S. 153, 98 S.Ct. 2279, 57 L.Ed.2d 117 (1978), holds directly that the appropriation of funds should not be construed to represent authorization of a project.
The Rod and Gun Club further buttresses this argument by referring this court to a number of cases where congressional funding of a project has not been viewed as representing implicit authorization of that project. See e. g. Greene v. McElroy, 360 U.S. 474, 505, 79 S.Ct. 1400, 3 L.Ed.2d 1377 (1959); D. C. Federation of Civic Associations v. Airis, 129 U.S.App.D.C. 125, 128-29, 391 F.2d 478, 481-82 (1968).
We are not convinced that these cases address issues that are necessarily analogous to those presented by this appeal, nor that they mandate the conclusion that courts can never construe appropriations as congressional authorization. However, we *746do conclude that T. V. A. v. Hill, although clearly distinguishable on the facts, nonetheless creates serious questions as to the Corps’ claim that the appropriation of funds for a project should generally be regarded as project authorization. Id. 437 U.S. at 190-92, 98 S.Ct. 2279.5
Reviewing the facts of this case, we find no evidence in the record that Congress intended the appropriations for the reregulating dam to be regarded as the authorization required by § 401, or that Congress as a whole believed that the reregulating dam had been authorized.
Admittedly, there is some evidence that when the Corps approached Congress for funds for the reregulating dam it asserted without challenge by congressional committee members that the dam had been authorized. Moreover, at least one report of the Senate Committee on Public Works refers to the reregulating dam as if it had been authorized. S.Rep.No.93-615, 93rd Cong., 1st Sess. 64 (1973).
We are hesitant, as was the Supreme Court in T. V. A. v. Hill, to interpret isolated remarks in committee hearings or reports as expressions of the intent or knowledge of Congress. T. V. A. v. Hill, supra, 437 U.S. at 191-92, 98 S.Ct. 2279; see S. E. C. v. Sloan, 436 U.S. 103, 121, 98 S.Ct. 1702, 56 L.Ed.2d 148 (1978).
We are confronted in this case with a specific statute that requires congressional authorization of dam projects. We find no evidence that the remarks contained in the committee reports, which asserted that such authorization had been obtained, were the product of a considered review of the issue.
We similarly find no indication that the appropriations for the reregulating dam were intended to satisfy the mandate of § 401,6 and in fact there is some indication that Congress might have mistakenly relied upon assertions by the Corps that the LAURD project had been specifically authorized when it appropriated funds for the project. See, e. g., Public Works for Water, Pollution Control, and Power Development and Atomic Energy Commission Appropriations, Hearings on H.R.No.18127 Before the Senate Appropriations Committee, 91st Cong., 2d Sess. 1779 (1971).
Without expressly reaching the general question whether appropriations as a rule constitute authorization, we find in this case that the congressional authorization required under § 401 was not conferred by appropriations alone. See Atchison, Topeka and Santa Fe Railway Co. v. Callaway, supra, at 620.
C. THE WATER RESOURCES DEVELOPMENT ACT.
The Corps finally argues that the Water Resources Development Act of 1974 authorized the construction of generators in the reregulating dam, and that the reregu*747lation dam was therefore authorized by necessity.
The Water Resources Development Act provides in relevant part:
Sec. 1. (a) The Secretary of the Army, acting through the Chief of Engineers, is hereby authorized to undertake the phase 1 design memorandum stage of advanced engineering and design of the following multi-purpose water resources development projects, substantially in accordance with, and subject to the conditions recommended by the Chief of Engineers in, the reports hereinafter designated. . .
The project for installation of power generating facilities at the Libby Reregulating - Dam, Kootenai River, Montana: Senate Document Numbered 93-29, at an estimated cost of $75,000.
88 Stat. 12-13. (Emphasis added.)
We agree with the Rod and Gun Club that that Act on its face authorizes only advance design studies, and not the construction of generators for the reregulating dam. Although explicit authorization of generators for the reregulating dam would create a strong inference that Congress intended to authorize the facility in which they were to be placed, we do not find that the authorization only of design studies is equally persuasive. We conclude that the Water Resources Development Act did not authorize the reregulating dam by necessity.
D. CONCLUSION.
Because the reregulating dam has not been authorized by Congress as required by § 401, this court need not look further at the equities employed by the district court to support the injunction. United States v. City and County of San Francisco, 310 U.S. 16, 30-31, 60 S.Ct. 749, 84 L.Ed. 1050 (1940). Our conclusion that the reregulating dam was not authorized bars its continued construction.
II.
THE ENVIRONMENTAL IMPACT STATEMENT
In light of our conclusion that the reregulating dam was not authorized by Congress, we do not reach the issue of the adequacy of the Environmental Impact Statement. If the Corps approaches Congress for authorization of the LAURD Project, it may well find it necessary either to prepare a new EIS or update the one adopted in 1974 to reflect recent developments noted by the district court. In any event, the environmental issues presented when and if the reregulation dam is authorized will likely turn on facts substantially different than those presented here, and are best left to the district court’s determination.
III.
THE DISTRICT COURT’S ENJOINING OF THE ADDITION OF TURBINES TO THE LIBBY DAM
There is no dispute that the addition of four turbines to the main Libby Dam was authorized by the Flood Control Act of 1950. Although such turbines may not be fully utilized without a reregulating dam, we feel that the court erred in enjoining their installation. Because the turbines have been authorized, the decision whether to proceed with their installation in light of our holding as to the reregulation dam is one for the Corps and Congress, not for us. We see no adverse environmental' impact resulting from the addition of the turbines alone, and therefore reverse the district court’s order as it pertains to the continued construction and installation of the turbines authorized for the main Libby Dam.
Presently pending are motions by the Corps for'reconsideration of our earlier order denying the Corps’ request for a stay of the injunction pending appeal, a motion by the Corps for summary reversal, and a motion by the Rod and Gun Club for clarification of our order allowing for continued expansion on the main Libby Dam.
Consistent with our holding on the authorization question, the Corps’ motion for reconsideration and for summary reversal are denied. The Rod and Gun Club’s motion *748for clarification relates to the issue whether the Corps should be allowed to construct additional turbines in the main Libby Dam, and is addressed by Section III of this opinion.
The Corps is enjoined from awarding contracts for the construction of the reregulating dam until authorization therefor is obtained from Congress.
Reversed in part and affirmed in part.
. At appellant’s request these appeals were expedited, argued on February 8, 1979 before a special panel, and considered on the appendix submitted by appellants. We deem that the appeal in 78-3297 has not been perfected, briefed or argued and that appeal is dismissed. Our opinion herein disposes of any issues that might have been raised in that appeal.
. Judge Kennedy suggests in his dissent that this court should not inquire into whether “internal procedures of Congress were correctly followed, precedent to the enactment of a law. Field v. Clark, 143 U.S. 649, 672, 676-77, 12 S.Ct. 495, 36 L.Ed. 294 (1892).” We make no such inquiry in this case. Rather, we are confronted with a duly enacted statute that requires Congress as a whole to authorize dam projects, including federally funded projects. It is the duty of the courts, when they must, to inquire whether Congress has satisfied the mandate of 33 U.S.C. § 401. See United States v. Arizona, 295 U.S. 174, 55 S.Ct. 666, 79 L.Ed. 1371 (1935). We therefore do not view § 401 as merely an “internal procedure of Congress.”
. We note in this regard that H.R.Doc.No.531 contains an extended and detailed discussion of several aspects of the Libby Dam. However, the document’s sole reference to reregulation is in paragraph 165.
. The record is unclear as to exactly how much of the estimated $250,000,000 cost of the LAURD project has been appropriated. Counsel at oral argument indicated that Congress has appropriated approximately $35,000,000 to date.
The LAURD project, however, includes both installation of additional generators on the main dam and construction of the reregulating dam. The Corps has not indicated what portion of the $35,000,000 was appropriated for the reregulating dam alone.
. The cases relied upon by the dissent to reach a contrary conclusion involve the limited issue of land condemnation. In such a context, this court and others have held that when a government officer has been given broad congressional authorization to acquire land for public uses, statutory authorization to procure specific real estate “may be evidenced by the making of an appropriation as well as by a specific authorization to acquire.” See, e. g., United States v. Kennedy, 278 F.2d 121, 122 (9th Cir. 1960); Polson Logging Co. v. United States, 160 F.2d 712, 714 (9th Cir. 1947).
In light of more recent decisions, we hesitate to apply these land condemnation cases to the question whether appropriations alone will satisfy the specific consent requirement of § 401.
Similarly, neither United States v. Arizona, 295 U.S. 174, 55 S.Ct. 666, 79 L.Ed. 1371 (1935), nor Wisconsin v. Duluth, 96 U.S. 379, 24 L.Ed. 668 (1877), is factually analogous to this case. Neither decision holds explicitly that appropriations constitute congressional authorization for dam construction.
. In T. V. A. v. Hill, the Supreme Court was confronted with a record showing that various congressional committees had specifically opined that continued construction of the Tellico Dam was proper notwithstanding the Endangered Species Act. 437 U.S. at 170-71, 98 S.Ct. 2279. The Court nonetheless held that such statements were not persuasive evidence that Congress as a whole intended to repeal that Act. Id. at 191, 98 S.Ct. 2279. In this case, the Corps has offered no evidence that the various appropriations committees ever considered the authorization issue. Thus, we find even less direct evidence than existed in T. V. A. v. Hill that Congress intended appropriations to be equated with authorization.