§ 15.01.800. Disinfection of culinary water lines.

A.

General requirements. All culinary water lines shall be disinfected by chlorination prior to use as outlined in this section.

B.

Chlorination. After flushing, all culinary water lines shall be disinfected by chlorination. Chlorination shall provide a minimum of twenty-five ppm residual after twenty-four hours contact in the pipeline. This may be expected with an application of fifty ppm although some conditions may require more. Chlorine, in the form of one percent slurry of high test calcium hypochlorite (HTH, Perchloron, Pittchlor, etc. which are seventy percent available chlorine by weight) shall be fed into the pipeline in such a manner as to mix with the water flowing in the pipeline. (A one percent slurry results from mixing one pound of the calcium hypochlorite with eight and four-tenths gallons of water.)

The following table provides information as to the required quantity of slurry to be used per one hundred feet of pipe to provide a chlorine concentration of fifty ppm:

Pipe Size (in.)	Vol. of 100 ft. Length (gal.)	Req'd. Amount of Slurry (gal.)
1.5	9.2	0.07
2	16.3	0.12
2.5	25.5	0.18
3	36.7	0.26
4	65.3	0.47
6	147	1.05
8	261	1.87
10	408	2.92
12	588	4.2

 

During the process of chlorinating the pipeline all valves, fire hydrants, and other pipeline appurtenances shall be operated several times to provide sufficient contact with the chlorinating agent. Following chlorination, the water line shall be drained and thoroughly flushed and, if necessary, re-chlorinated until a satisfactory bacteriological test is obtained. After twenty-four hours of chlorination, the contractor shall obtain a water sample, upon which the contractor will have a bacteriological test performed. The lab will provide a copy of the test to the city. The contractor shall pay the cost of the bacteriological test. Disinfection shall conform to the requirements of AWWA C651-86 (or latest edition).

(Ord. No. 2007-07-31, §§ 9.10—9.10.2, 7-10-2007; Ord. No. 2010-11-24, § 2, 11-23-2010)