opinion: Mr. JusticeDouglas
  delivered the opinion of the
  This is a suit for condemnation of land instituted by the United States against respondent power company. A single question of valuation is presented. It is whether the just compensation which the United States must pay by force of the Fifth Amendment includes the value of the land as a site for hydroelectric power operations. The Fourth Circuit Court of Appeals held that it does. 215 2d 592. The Court of Appeals for the Fifth Circuit reached the same result in litigation involving other lands the same hydroelectric project. United States v. Twin. City Power Co., 221 F. 2d 299. We granted the petition certiorari in the former case because of the importance the issue presented. 348 U. S. 910.
  The condemnation proceedings are part of the procedure for completion of the Clark Hill project on the Savannah River, a navigable stream in southeastern United States. The Clark Hill project is the first in series of steps recommended by the Chief of Army Engineers for the improvement of the basin of that river. R. Doc. No. 657, 78th Cong., 2d Sess. That Report conceives of the Clark Hill project as serving multiple purposes — hydroelectric, flood control, and navigation. It states that the Clark Hill project, “if suitably constructed operated primarily for hydroelectric-power develop-would incidentally reduce downstream flood dam- and improve low-water flows for navigation.” Id., p. 3. Congress approved this project as part of “the comprehensive development of the Savannah River Basin for flood control and other purposes.” Section 10 of the Flood Control Act of 1944, 58 Stat. 887. And see United States ex rel. Chapman v. Federal Power Commission, 345 U. S. 153, 170.
  The Court of Appeals concluded that the improvement of navigation was not the purpose of the taking but that the Clark Hill project was designed to serve flood control and water-power development. 215 F. 2d, at 597. It is not for courts, however, to substitute their judgments for congressional decisions on what is or is not necessary for the improvement or protection of navigation. See Arizona v. California, 283 U. S. 423, 455-457. The role of the judiciary in reviewing the legislative judgment is a narrow one in any case. See Berman v. Parker, 348 U. S. 26, 32; United States ex rel. TV A v. Welch, 327 U. S. 546, 552. The decision of Congress that this project will serve the interests of navigation involves engineering and policy considerations for Congress and Congress alone to evaluate. Courts should respect that decision until and unless it is shown “to involve an impossibility,” as Mr. Justice Holmes expressed it in Old Dominion Co. v. United States, 269 U. S. 55, 66. If the interests of navigation are served, it is constitutionally irrelevant that other purposes may also be advanced. United States v. Appalachian Power Co., 311 U. S. 377, 426; Oklahoma ex rel. Phillips v. Atkinson Co., 313 U. S. 508, 525, 533-534. As we said in the Appalachian Power Co. case, “Flood protection, watershed development, recovery of the cost of improvements through utilization of power are likewise parts of commerce control.” 311 U. S., at 426.
  The interest of the United States in the flow of a navigable stream originates in the Commerce Clause. That Clause speaks in terms of power, not of property. But the power is a dominant one which can be asserted to the any competing or conflicting one. The power is a privilege which we have called “a dominant servitude” (see United States v. Commodore Park, Inc., 324 U. S. 386, 391; Federal Power Commission v. Niagara Mohawk Power Corp., 347 U. S. 239, 249) or “a superior navigation easement.” United States v. Oerlach Live Stock Co., 339 U. S. 725, 736. The legislative history and construction of particular enactments may lead to the conclusion that Congress exercised less than its constitutional power, fell short of appropriating the flow of the river to the public domain, and provided that private rights existing under state law should be compensable or otherwise recognized. Such were United States v. Gerlach Live Stock Co., supra, and Federal Power Commission v. Niagara Mohawk Power Corp., supra. We have a different situation here, one where the United States displaces all competing interests and appropriates the entire flow of the river for the declared public purpose.
  We can also put aside such cases as United States v. Kansas City Life Ins. Co., 339 U. S. 799, where assertion of the dominant servitude in the navigable river injured property beyond the bed of the stream. Here we are dealing with the. stream itself, for it is in the water power that respondents have been granted a compensable interest.
  however, that the special water-rights value should be awarded the owners of this land since it lies not in the bed of the river nor below high water but above and beyond the ordinary high-water mark. An effort is made by this argument to establish that this private land is not burdened with the Government’s servitude. The flaw in that reasoning is that the landowner here seeks a value in the flow of the stream, a value inheres in the Government’s servitude and one that under our decisions the Government can grant or with-as it chooses. It is no answer to say that payment is sought only for the location value of the fast lands. That special location value is due to the flow of the stream; and if the United States were required to pay the judgments below, it would be compensating the landowner for the increment of value added to the fast lands if the flow of the stream were taken into account.
  That is illustrated by United States v. Chandler-Dunbar Co., 229 U. S. 53, the case that controls this one. In that case a private company installed a power project in St. Mary's River under a permit from the Government, revocable at will. The permit was revoked, Congress appropriating the entire flow of the stream for navigation purposes. The Court unanimously held that the riparian owner had no compensable interest in the water power of which it had been deprived. Mr. Justice Lurton, speaking for the Court, said, “Ownership of a private stream wholly upon the lands of an individual is conceivable; but that the running water in a great navigable stream is capable of private ownership is inconceivable.” Id., at 69. The Court accordingly reversed a judgment that awarded the riparian owner what respondents have obtained in this case, viz., “the present money value of the rapids and falls to the Chandler-Dunbar Company as riparian owners of the shore and appurtenant submerged land.” Id., at 74. The Court said, “The Government had dominion over the water power of the rapids and falls and cannot be required to pay any hypothetical additional value to a riparian owner who had no right to appropriate the current to his own commercial use.” Id., at 76. Some of the land owned by the private company was in the bed of the stream, some above ordinary high water. But the location of the land was not determinative. It was the dominion of the Government over the water power that controlled the decision. Both in Chandler-Dunbar and in this case it is the water power that creates the special value, whether the lands are above or below ordinary high water. The holding in Chandler-Dunbar led us to say in United States v. Appalachian Power Co., supra, at 424, that the “exclusion of riparian owners” from the benefits of the power in a navigable stream “without compensation is entirely within the Government’s discretion.” And again, “If the Government were now to build the dam, it would have to pay the fair value, judicially determined, for the fast land; nothing for the water power.” Id., at 427.
  The power company in the present case is certainly in no stronger position than the owner of the hydroelectric site in the Chandler-Dunbar case. While the latter was deprived of a going private power project by the Government, the present private owners never had a power project on the Savannah and as a result of the Government’s pre-emption never can have one.
  It is no answer to say that these private owners had interests in the water that were recognized by state law. We deal here with the federal domain, an area which Congress can completely pre-empt, leaving no vested private claims that constitute “private property” within the meaning of the Fifth Amendment. Location of the lands might under some circumstances give them special value, as our cases have illustrated. But to attach a value of water power of the Savannah River due to location and to enforce that value against the United States would go contra to the teaching of Chandler-Dunbar — “that the running water in a great navigable stream is capable of private ownership is inconceivable.” 229 U. S., at 69.
  The holding of the Chandler-Dunbar case that water power in a navigable stream is not by force of the Fifth Amendment a compensable interest when the United States asserts its easement of navigation is in harmony with another rule of law expressed in United States v. Miller, 317 U. S. 369, 375.
  “Since the owner is to receive no more than indemnity for his loss, his award cannot be enhanced by any gain to the taker. Thus, although the market value of the property is to be fixed with due consideration of all its available uses, its special value to the condemnor as distinguished from others who may or may not possess the power to condemn, must be excluded as an element of market value.”
  The Court in the Chandler-Dunbar case emphasized that it was only loss to the owner, not gain to the taker, that is compensable. 229 U. S., at 76. If the owner of the fast lands can demand water-power value as part of his compensation, he gets the value of a right that the Government in the exercise of its dominant servitude can grant or withhold as it chooses. The right has value or is an empty one dependent solely on the Government. What the Government can grant or withhold and exploit for its own benefit has a value that is peculiar to it and that no other user enjoys. Cf. U. S. ex rel. T. V. A. v. Powelson, 319 U. S. 266, 273 et seg. To require the United States to pay for this water-power value would be to create private claims in the public domain.
  Reversed.
  In the Chandler-Dunbar case, an award of compensation was made for the value of the land for a lock and canal, passing “around the falls and rapids.” United States v. Chandler-Dunbar Co., 229 U. S., at 67, 76-78. It may be that the Court was influenced by the fact that, on the special facts of the case, the use of the land for canals and locks was wholly consistent with the dominant navigation servitude of the United States and indeed aided navigation. Whatever may be said for that phase of the case, it affords no support for respondent, since water-power value, held to be compensable by the Court of Appeals, was ruled to be noncompensable in the Chandler-Dunbar case.
instruction: What follows is an opinion from the Supreme Court of the United States. Your task is to determine whether the decision of the court whose decision the Supreme Court reviewed was itself liberal or conservative. In the context of issues pertaining to criminal procedure, civil rights, First Amendment, due process, privacy, and attorneys, consider liberal to be pro-person accused or convicted of crime, or denied a jury trial, pro-civil liberties or civil rights claimant, especially those exercising less protected civil rights (e.g., homosexuality), pro-child or juvenile, pro-indigent pro-Indian, pro-affirmative action, pro-neutrality in establishment clause cases, pro-female in abortion, pro-underdog, anti-slavery, incorporation of foreign territories anti-government in the context of due process, except for takings clause cases where a pro-government, anti-owner vote is considered liberal except in criminal forfeiture cases or those where the taking is pro-business violation of due process by exercising jurisdiction over nonresident, pro-attorney or governmental official in non-liability cases, pro-accountability and/or anti-corruption in campaign spending pro-privacy vis-a-vis the 1st Amendment where the privacy invaded is that of mental incompetents, pro-disclosure in Freedom of Information Act issues except for employment and student records. In the context of issues pertaining to unions and economic activity, consider liberal to be pro-union except in union antitrust where liberal = pro-competition, pro-government, anti-business anti-employer, pro-competition, pro-injured person, pro-indigent, pro-small business vis-a-vis large business pro-state/anti-business in state tax cases, pro-debtor, pro-bankrupt, pro-Indian, pro-environmental protection, pro-economic underdog pro-consumer, pro-accountability in governmental corruption, pro-original grantee, purchaser, or occupant in state and territorial land claims anti-union member or employee vis-a-vis union, anti-union in union antitrust, anti-union in union or closed shop, pro-trial in arbitration. In the context of issues pertaining to judicial power, consider liberal to be pro-exercise of judicial power, pro-judicial "activism", pro-judicial review of administrative action. In the context of issues pertaining to federalism, consider liberal to be pro-federal power, pro-executive power in executive/congressional disputes, anti-state. In the context of issues pertaining to federal taxation, consider liberal to be pro-United States and conservative pro-taxpayer. In miscellaneous, consider conservative the incorporation of foreign territories and executive authority vis-a-vis congress or the states or judcial authority vis-a-vis state or federal legislative authority, and consider liberal legislative veto. The lower court's decision direction is unspecifiable if the manner in which the Supreme Court took jurisdiction is original or certification; or if the direction of the Supreme Court's decision is unspecifiable and the main issue pertains to private law or interstate relations