Rates charged for services furnished by any system, project or combined system purchased, constructed, improved, enlarged, extended or repaired under the provisions of this chapter shall not be subject to supervision or regulation by any State bureau, board, commission or other like instrumentality or agency of the State and it shall not be necessary for any borrower operating under the provisions of this chapter to obtain any franchise or other permit from any State bureau, board, commission or other instrumentality of the State in order to construct, improve, enlarge, extend or repair any system, project or combined system named in this chapter. But the functions, powers and duties of the Department of Health and Environmental Control shall remain unaffected by this chapter.