The State of Nebraska hereby assents to the provision of an Act of Congress entitled the Federal Water Projects Recreation Act, approved July 9, 1965, Public Law 89-72, 89th Congress, and to any and all existing amendments thereto, including those found in an Act of Congress entitled the Water Resources Development Act of 1974, approved March 7, 1974, Public Law 93-251, 93rd Congress. The Game and Parks Commission is authorized and empowered to perform, within the limits of available funding, such acts as may be necessary to administer, operate, maintain, and replace land and water areas for recreation or fish and wildlife purposes or for both of such purposes in accordance with the provisions of such act as amended. The commission is further authorized to execute an agreement, the performance of which shall be contingent upon funds being made available therefor, to bear the separable costs of federal projects allocated to either or both of such purposes in the proportion specified by such act, as amended, and to pay or repay such costs in accordance with the terms of such agreement.