There is hereby established a separate fund in the Treasury of the United States to be known as the Lower Colorado River Basin Development Fund (hereafter called the “development fund”), which shall remain available until expended as hereafter provided.
Except as provided in subsection (f), revenues credited to the development fund shall not be available for construction of the works comprised within any unit of the project herein or hereafter authorized except upon appropriation by the Congress.
Funds credited to the development fund pursuant to subsection (b) and paragraphs (1) and (3) of subsection (c), the portion of revenues derived from the sale of power and energy for use in the State of Arizona pursuant to subsection (c)(2) in excess of the amount necessary to meet the requirements of paragraphs (1) and (2) of subsection (d), and any annual payment by the Central Arizona Water Conservation District to effect repayment of reimbursable Central Arizona Project construction costs, shall be credited annually against the annual payment owed by the Central Arizona Water Conservation District to the United States for the Central Arizona Project.
The Secretary of the Treasury shall invest such portion of the development fund as is not, in the judgment of the Secretary of the Interior, required to meet current needs of the development fund.
Any obligation acquired by the development fund may be sold by the Secretary of the Treasury at the market price.
None of the provisions of this section, including paragraphs (2)(A) and (3)(A), shall be construed to make any of the funds referred to in this section available for the fulfillment of any Federal obligation relating to the payment of OM&R charges if such obligation is undertaken pursuant to Public Law 95–328, Public Law 98–530, or any settlement agreement with the United States (or amendments thereto) approved by or pursuant to either of those acts.
All revenues credited to the development fund in accordance with subsection (c)(2) of this section (excluding only those revenues derived from the sale of power and energy for use in Arizona during the payout period of the Central Arizona Project as authorized herein) and such other revenues as remain in the development fund after making the payments required by subsections (d) and (f) of this section shall be available (1) to make payments, if any, as required by sections 616aa–1 and 620d–1 of this title, (2) for repayment to the general fund of the Treasury the costs of each salinity control unit or separable feature thereof  the costs of measures to replace incidental fish and wildlife values foregone, and the costs of on-farm measures payable from the Lower Colorado River Basin Development Fund in accordance with sections 1595(a)(2), 1595(a)(3), and 1595(b) of this title and (3) upon appropriation by the Congress, to assist in the repayment of reimbursable costs incurred in connection with units hereafter constructed to provide for the augmentation of the water supplies of the Colorado River for use below Lee Ferry as may be authorized as a result of the investigations and recommendations made pursuant to sections 1511 and 1513(a) of this title.
The interest rate applicable to those portions of the reimbursable costs of each unit of the project which are properly allocated to commercial power development and municipal and industrial water supply shall be determined by the Secretary of the Treasury, as of the beginning of the fiscal year in which the first advance is made for initiating construction of such unit, on the basis of the computed average interest rate payable by the Treasury upon its outstanding marketable public obligations which are neither due nor callable for redemption for fifteen years from the date of issue.
Business-type budgets shall be submitted to the Congress annually for all operations financed by the development fund.