15A NCAC 18C .0904      PIPE LAYING

(a)  Trenching, pipe laying, and backfilling shall be accomplished in a manner to prevent damage to and misalignment of the pipe. Water mains shall be buried to a depth below the frost line or to a depth sufficient to provide a minimum of 30 inches cover, whichever is greater. In cases where it is impracticable to provide 30 inches of cover taking into consideration feasibility and cost, a deviation may be approved on a case-by-case basis, if supported by data from the design engineer including consideration of pipe material, cover material, land cover, land use, land slope, the depth of the frost line, and the location of other utilities.

(b)  To allow for construction and repair, a minimum distance of 12 inches shall be maintained between the outside of the water main and the outside of other utilities.

(c)  If an engineer demonstrates it is impractical to maintain the separation distances required by this Rule, taking into consideration feasibility, cost, and the factors set forth in this Paragraph, a deviation may be approved on a case-by-case basis if supported by data and alterative construction criteria submitted by the design engineer. Data and alterative construction criteria submitted by the design engineer to justify the deviation shall describe:

(1)           the rationale for determining that separation criteria described in Paragraphs (a) and (b) of this Rule are impracticable;

(2)           the extent of the deviation from separation criteria in Paragraphs (a) and (b) of this Rule;

(3)           a consideration of pipe materials, pressure ratings, type of joints for water main and non-potable water line, and soil conditions;

(4)           the ability to provide adequate work space to repair or replace pipe segments or other utility infrastructure without causing damage to or otherwise compromising the integrity of pipes; and

(5)           the rationale for determining that the deviation will not result in unreasonable risk to public health.

History Note:        Authority G.S. 130A-315; 130A-317; P.L. 93-523;

Eff. January 1, 1977;

Readopted Eff. December 5, 1977;

Pursuant to G.S. 150B-21.3A, rule is necessary without substantive public interest Eff. November 23, 2015;

Amended Eff. July 1, 2019.