20 CAR § 137-105 – Water supply design and operation

(a) The water supply shall be designed and operated in accordance with the Rules Pertaining to Semi Public Water Supplies, 20 CAR pt. 141.
(b)
1. (1) Prior to placing the water supply system into use, all portions of the system shall be disinfected by:
  1. (A) Adding a chlorine solution of not less than fifty parts per million (50 ppm); and
  2. (B) Retaining the mixture within all portions of the system for at least twenty-four (24) hours.
2. (2) Following disinfection:
  1. (A) The system is to be flushed thoroughly of the chlorine solutions; and
  2. (B) Then bacteriological water samples shall be collected daily and submitted to the Department of Health until two (2) consecutive samples show the water to be safe for drinking.
(c) During normal operation conditions, a chlorine residual of at least two-tenths parts per million (0.2 ppm) shall be maintained at all times throughout the distribution system.