(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.
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Awwa c free download – Google Docs
This hose must be removed during the hydrostatic pressure test. Documents Flashcards Grammar checker. Samples for bacteriological analysis shall be collected in sterile bottles treated with sodium thiosulfate, in accordance with Section —Samples of C651–05 Methods for the Examination of Water and Wastewater. Samples shall be tested for bacteriological quality in accordance with Standard Methods for the Examination of Water and Wastewater and shall show the absence of coliform bacteria.
It should be recognized that the primary means of ensuring the awwz integrity of a main are the sanitary handling of materials, the practices during construction, and continual inspection of work.
Generally, it is easier to disinfect a new main than one that has had emergency repairs in terms of access, sanitary control, and the time available for disinfection, sampling, and testing. Pipe delivered for construction shall be strung to minimize the entrance of foreign material.
Before approving a main for release, take an initial set of samples and then resample again after a minimum of 16 hr using the sampling site procedures outlined.
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Specific situations not captured below need to be evaluated and the appropriate disinfection and sampling methods followed. If the initial disinfection fails to produce c65105 bacteriological results, or if other results indicate unacceptable water quality, the main may be reflushed and shall be resampled.
The party that supplies material or services.
AWWA C Disinfecting Water Mains
Size and number of taps per Table 3. Precautions shall be taken to ensure that air pockets are eliminated. Available chlorine is expressed as a percent of weight when the concentration is 5 percent or less, and usually as a percent of volume for higher concentrations.
Drainage should take place away from the construction or work area. Materials such as jute or hemp shall not be used. Because of the differences between initial installation and repair, the disinfection requirements for each situation are also different. In most other situations, the water main can be maintained pressurized until the break site is secured and the pipe is fully exposed.
Ozone and chemical cleaners have been used, and these warrant further investigation. Major revisions made to the standard in this edition include the following: The party that manufactures, fabricates, or produces materials or products. Hydrostatic pressure tests should be conducted with potable water. Note that the procedures explained in Sec. Disinfection should be accomplished by the procedures in Sec.
Exposure to high levels of chlorine or high pH can cause severe irritation to customers. This figure applies to pipes up to and including 8-in. Temporary water service lines to customers during main repair activities shall be disinfected prior to use.
Four methods of disinfecting newly constructed water mains are described in 6c51-05 standard: The water main may then be returned to service after flushing to scour the pipe and obtain three volumes of water turnover. Water mains taken out of service for inspection, repair, or other activities may or may not require disinfection and sampling, depending on the risk of awws. If chemical contamination occurs, such as a hydraulic oil leak or petroleum product spill, the pipe sections exposed to the contamination should be replaced and not reused for potable water applications.
Figure 1 applies to pipes with diameters aww in. The slug method is suitable for use in large-diameter mains where the awwx of water makes the continuous-feed method impractical and difficult to achieve for short attachments. In this situation, activities are well controlled and a full shutdown is not needed, thus maintaining positive pressure to the area of shutdown and around the break site at all times.
Final connecting of the newly disinfected water main to the active distribution system without sacrificing sanitary practices and conditions.
Where such flow rates are not aqwa, flushing at the maximum expected flow rate for the line for 2—3 volumes may be acceptable. Chlorinating and adequately documenting the process used for disinfection. Calcium hypochlorite tablets 5-grams shall be placed in wwwa upstream end of each section of pipe to be disinfected, including branch lines. The sampling pipe must be dedicated and clean and disinfected and flushed prior to sampling.
Water Main Break Guidance Manual epa. Also, the chlorinated water can be high in disinfection by-products. Responsibility for tapping existing mains and connections to new c6510-5 Sec.
A Information on Application of This Standard The repair site should be accessible and the trench adequately dewatered so that the repair site can be cleaned and disinfected by spraying or swabbing with a minimum 1 percent chlorine solution. The more closely the rate of delivery awaw correlated to the rate of pipe laying, the lower the risk of contamination.
Determine additives requirements including applicable standards. Four methods of chlorination are explained in this section: The disinfection procedure selected should be determined by the conditions and severity of the main break. For larger mains, pigging or other suitable method acceptable to the purchaser is an option in place of high velocity flushing.
AWWA C651-14 Disinfecting Water Mains
Developed a 6c51-05 for evaluating risk during pipe repairs and the level of disinfection and sampling needed under those conditions Sec. The affected pipe shall be xwwa by swabbing or spraying with a minimum 1 percent chlorine solution. Factors to consider when choosing a method should include the length and diameter of the main, type of joints present, availability of materials, equipment required for disinfection, training of the personnel who will perform the disinfection, and safety concerns.