Housing authorities may serve as redevelopment authorities. Such authorities are empowered to undertake urban renewal projects and issue tax increment bonds to finance redevelopment projects. Blighted property may be acquired, cleared, and assembled for redevelopment. Under tax increment financing, the new tax revenue resulting from a successful redevelopment project is earmarked for public investments that made redevelopment possible. County approval is required unless county taxes are exempted from the tax increment provisions (except in Davidson and Shelby counties). T.C.A. §§ 13-20-202–216.