Louisiana Administrative Code
Title 51 - PUBLIC HEALTH-SANITARY CODE
Part XII - Water Supplies
Chapter 3 - Water Quality Standards
Section XII-353 - Disinfection of New Water Supplies [formerly paragraph 12:020-2]

A. Pumps, pipes, wells, tanks and other parts of new systems shall be thoroughly disinfected by the use of chlorine or chlorine compounds before being placed in use. The rate of application of chlorine shall be in such proportion to the rate of water entering the pipe or other appurtenances that the chlorine dose applied to the water shall be at least 50 mg/l. Chlorinated water shall be retained long enough to destroy non-spore-forming bacteria. The period shall be at least three hours and preferably longer, as may be directed. After the chlorine treated water has been retained for the required time, the chlorine residual at pipe extremities and at other representative points shall be at least 5 mg/l. If the residual is less than 5 mg/l, the disinfection procedure shall be repeated until a 5 mg/l residual is obtained, as required above.

B. [formerly paragraph 12:020-3] Large storage tanks may be disinfected by washing down the interior of the tank with a chlorine solution having at least 200 mg/l available chlorine and then washing the interior of the tank with potable water and wasting the wash water.

C. [formerly paragraph 12:020-4] Water from new systems, or from new parts of existing systems, shall not be furnished for consumer's use until tests performed by a laboratory which is certified by the state heath officer have shown the new system or new part of the system to be free from contamination by coliform bacteria (following EPA approved procedures prescribed in Standard Methods for the Examination of Water and Wastewater, Nineteenth Edition). Samples shall not be collected from the new facilities until such new facilities have been disinfected as prescribed in §353. A above, and the chlorinated water thoroughly flushed from the system.