(Revision of ANSI/AWWA C). Copyright © This document is an American Water Works Association (AWWA) standard. It is not a. 1, , AWWA issued the updated ANSI/AWWA C 14 standard, Disinfecting Water Mains, a result of the review that AWWA standards must go through. AWWA Standard for Disinfecting Water Mains – Jun 1, – Ansi/AWWA C DS60 Water Supply Distribution Standard – Pipelines Other.
|Published (Last):||17 March 2011|
|PDF File Size:||4.72 Mb|
|ePub File Size:||8.21 Mb|
|Price:||Free* [*Free Regsitration Required]|
What is that symbol. The vacuum-operated chlorinator mixes the chlorine gas in solution water; the booster pump then injects the chlorine solution into the main to be disinfected. Between the time the satisfactory bacteriological sample results are received and the time that the connection piping is installed, the ends of the piping must be sealed with plastic wraps, watertight plugs, or caps.
It should be noted if the line is depressurized or opened to the environment prior to or during repair, the sanitary integrity of the pipe is compromised and it is critical to follow sanitary procedures throughout the repair—not just as it is being returned to service.
Flushing locations, rates of flushing, and locations of drainage facilities Sec. Clarified differences in the requirements between new and repaired mains foreword II. Standard Methods for the Examination of Water and Wastewater. The repair site should be cleaned and disinfected by spraying or swabbing with a minimum 1 percent chlorine solution. Wastewater System Maintenance Agreement.
Liquid chlorine gas shall be used only 1 in combination with appropriate gas-flow chlorinators and ejectors to provide a controlled high-concentration solution feed to the water to be chlorinated; 2 under the direct supervision of someone familiar with the biological, chemical, and physical properties of liquid chlorine gas and who is trained and equipped to handle any emergency that may arise; and 3 when appropriate safety practices are observed to protect working personnel and the public.
This edition approved June 8, The tablet method cannot be used unless the main can be kept clean and dry.
AWWA C651-14 Disinfecting Water Mains
OSHA requirements for confined space need to be addressed before entering a pipeline. Before the main is chlorinated, it shall be filled with potable water to eliminate air pockets and flushed to remove particulates. This American National Standard may be revised or withdrawn at any time. Potable water shall be used for disinfection, hydrostatic pressure testing, and flushing. After construction is completed, the main shall be disinfected using the continuous-feed, slug, or spray methods.
awwa c – Edit & Fill Out Online Templates, Download in Word & PDF |
The disinfection procedure selected should be determined by the conditions and severity of the main break. Hoses and fire hydrants are not recommended for the collection of samples that will be used to make decisions on the bacteriological quality of drinking water.
The utility should decide which of these methods is most suitable for a given situation. Preliminary flushing removes light particulates from the main but not from the pipe-joint spaces.
Safety Practice for Water Utilities. After 30 min, fill line and sample as described in Sec.
AWWA C Disinfecting Water Mains
This page intentionally blank. In the absence of a meter, the rate may be approximated using a Pitot gauge in the discharge, measuring the time to fill a container of known volume, or measuring the trajectory of the discharge and using the formula shown in Figure 2. The slug method results in appreciable savings of chemicals used to disinfect long large-diameter mains. If the main is flooded during construction, it shall be cleared of the floodwater by draining and flushing with potable water until the main is clean.
Specific situations not captured below need to be evaluated and the appropriate disinfection and sampling methods followed. Henderson, Consultant, Concord, Mass. This method reduces the volume of heavily chlorinated water to be flushed to waste. Smith, Smith LaSalle Inc.
Because of the differences between initial installation and repair, the disinfection requirements for each situation are also different.
In their latest editions, they form a part of this standard to the extent specified within c651-0 standard.
Pipe delivered for construction shall be strung to minimize the entrance of foreign material. AWWA members provide solutions to improve public health, protect the environment, strengthen the economy, and enhance our quality of life.
Precautions shall be taken to ensure that air pockets are eliminated. Figure 1 applies wawa pipes with diameters 4 in. If direction of flow is not known, samples shall be collected on either side of the repair site. Water Main Break Guidance Manual epa.
This standard describes the process for evaluating the risk under different conditions.