Va. Code § 21-118.5
Whenever the board of supervisors of any county, as the governing board of such county, shall enter into, or has heretofore entered into, an agreement with one or more sanitary districts located within such county whereby the county has agreed to connect, operate, maintain, alter, improve, add to and extend within and without the territory of such sanitary district or districts the water supply or sewerage systems, or the water supply and sewerage systems, of such county and such district or districts, or the water supply or sewerage systems, or the water supply and sewerage systems, of two or more such sanitary districts, in the manner of and as a unified single water supply or sewerage system, or a unified single water supply and sewerage system, each of which is hereinafter referred to in this chapter as a "unified system," then, notwithstanding the provisions of the first sentence of § 21-118.4(e), such board of supervisors is empowered to fix and prescribe the rate of charge for the use of such unified system with a view to the needs of such unified system as a whole. Such unified system shall constitute a "project" and a "revenue producing undertaking" for the purposes of and as defined in the Public Finance Act, Chapter 26 (§ 15.2-2600 et seq.) of Title 15.2. Such county in respect of such project and revenue producing undertaking shall have all the powers granted to counties by the Public Finance Act. Water and sewer connection fees established by any county, city, town or sanitary district shall be fair and reasonable. Such fees shall be reviewed by the county, city, town or sanitary district periodically and shall be adjusted, if necessary, to assure that they continue to be fair and reasonable. Nothing herein shall affect existing contracts with bondholders which are in conflict with any of the foregoing provisions.
Va. Code § 21-118.5