(a) Definitions. For purposes of this section, the following definitions shall apply:
"Sewer structure" means a building drain, building sewer, private sewer or public sewer.
"Water supply system" means a water main, water pipe, water service line or public water main.
(b) A water supply system shall be protected from a sewer structure, as follows:
(1) Lateral separation: A water supply system shall be separated at least ten feet laterally from any existing or proposed sewer structure, except when:
(A) local conditions prevent a lateral separation of ten feet;
(B) the water supply system invert is at least 18 inches above the crown of the sewer structure; and
(C) the water supply system is either in a separate trench or in the same trench on an undisturbed earth shelf located to one side of the sewer structure.
(2) Vertical separation:
(A) A water supply system shall be laid so that its invert is 18 inches above the crown of a sewer structure whenever a water supply system crosses a sewer structure. The vertical separation shall be maintained for that portion of the water supply system located laterally within ten feet of a sewer structure. The length of the water supply system pipe shall be centered over the sewer structure, and it must be crossed with joints equidistant from the sewer structure.
(B) A vertical separation of 18 inches shall be maintained between the invert of the sewer structure and the crown of the water supply system where a water supply system crosses under a sewer structure. In addition, support must be provided to the sewer structure to prevent it from settling and breaking the water supply system. Construction shall be extended on each side of the crossing until the lateral distance from the water supply system to the sewer structure is at least ten feet.
(c) The water supply system shall be constructed of a type of ductile iron pipe or copper or copper-alloy tubing listed in Table 18-29-605.4, and the sewer structure shall be constructed of a type of cast-iron pipe, ductile iron pipe, copper or copper-alloy tubing or PVC pipe listed in Table 18-29-702.3 when:
(i) it is technically and economically impractical to obtain proper lateral separation as described in subsection (b)(1) above; or
(ii) it is technically and economically impractical to obtain proper vertical separation as described in subsection (b)(2) above; or
(iii) the water supply system passes under a sewer structure.
(d) Special conditions. Alternate proposals shall be presented to the Commissioner of Water Management when extreme topographical, geological or existing structural conditions make compliance with subsection (b) of this section technically and economically impractical. The Commissioner may approve such a proposal if in the Commissioner's determination it is watertight construction and structurally equivalent to an approved water main material.
(e) Water supply systems shall be separated by a minimum of 25 feet laterally from septic tanks, disposal fields and seepage beds.
(f) Water supply systems shall be protected against entrance of hydrocarbons through diffusion from any material used in the construction of the line.
(Amend Coun. J. 7-29-15, p. 3537, § 4; Amend Coun. J. 10-14-21, p. 37722, Art. VI, § 4)