AWWA C Disinfecting Water Mains. Current; Document Language: English; Published By: American Water Works Association (AWWA). This standard presents essential procedures for the disinfection of new and repaired potable water mains. All new water mains shall be disinfected before they. FIELD CHLORINATION. • AWWA/ANSI C – Disinfecting Water Mains. • First standard approved Sept. 30, • Latest revision June 1.

The disinfection requirements for new watermains as per Section 1. Dechlorination of discharged water is required for any water that is directed into surface water or if the stansard into the natural environment causes or is likely to cause an adverse effect, as per Condition 10 of Schedule B of the Municipal Drinking Water Licence. Watermain breaks with evident or suspected Contamination are classified as Category 2.

The operating authority shall implement the plan as prescribed and the watermain cannot sfandard put back in service c6511 the cleaning, disinfection and sampling is completed as per the plan unless a Water Advisory is declared. Due to the chlorine demand exerted by the copper, no minimum chlorine concentration is required following the 24 hour contact time, and the effectiveness of the disinfection process shall be demonstrated by the Microbiological sampling x651 to in section 1.

If Contamination is evident or suspected, the procedures defined under section 3 for Category 2 watermain breaks shall apply. Staged sampling shall be performed as follows: If chlorine disinfection was used, indicate initial concentration, contact time, final concentration and final concentration as percentage of initial concentration. Examples of watermain breaks that are typical of Category 2 are included below for illustrative purposes only:.

AWWA C / AWWA C / AWWA C – Disinfection Of Water Package

Appendix E The following flowchart depicts the requirements for special case Contamination sewage or chemical as a result of a watermain break. Staged sampling shall be performed as follows:. In developing these procedures, operating authorities may use best management practices that go beyond the minimum requirements in this document.

Examples of typical steps for Standarc 1, 2 and for special cases are attached as Appendices C, D and E respectively. Corrosion hole leak in a watermain with flow maintained until after an Air gap was created. The operating authority shall finalize the plan in agreement with the local Ministry office in consultation with the local Medical Officer of Health.

This document outlines procedures for disinfecting water mains as part of an addition, modification, replacement, extension, planned maintenance, or emergency repair standdard a municipal residential drinking water system. Operating authorities shall develop and document operating procedures for emergency watermain repairs within their systems. The discharged water is deemed to be a Class II spill for the purposes of O. Notification to the local Ministry office is not required for Category 2 watermain breaks unless: Notification to the local Ministry office is not required for Category 2 watermain breaks unless:.

Watermain disinfection procedure

Longitudinal watermain break with evident Contamination. If planned maintenance, standarv type of planned maintenance e. Flushed water may be discharged from a hydrant, plumbing or Appurtenances.

The requirements in this section also apply to temporary watermains. If an operating authority believes that contaminated water was directed to users, this will constitute an observation of improper disinfection in accordance with Section of Schedule 16 of O.

Upon completion of the excavation, the Operator-in-Charge OIC shall conduct a visual inspection to determine the nature of the break. Watermain repairs involving more than 6 metres of replaced pipe are also classified as Category 2.

Drinking water system operating authorities shall ensure that emergency repairs to watermains and Appurtenances are undertaken in accordance with this procedure by any person authorized to perform the repairs.

Category 1 watermain breaks are not defined as an observation of improper disinfection in accordance with Section of Schedule 16 of O. This procedure uses a risk management approach to categorize watermain breaks based on the potential for Contamination. If there is evident or suspected sewage Contamination of a watermain, in addition to the procedures in sections 3. For relining of existing watermains, the conditions of section 1. Appendix B Tools to help determine the category of watermain break – pictures Examples of watermain breaks that are typical of Category 1 are included below for illustrative purposes only: If, at any time, Contamination is evident or suspected, the break shall be reclassified as Category 2.

The local Ministry office shall be notified as soon as reasonably possible during business hours.

Service pipes of mm diameter and greater shall be considered as watermains for the purposes of this procedure. Skip to main content.

Where the operating authority opts to undertake Microbiological sampling, samples shall be considered distribution samples within the meaning of O. This section does not require that all of the information be recorded on a single form:. If the water level in the excavation rises such that the Air gap is not maintained after flow from the break has been discontinued, then the watermain break shall be classified as Category 2. There is no requirement to undertake Microbiological sampling for Category 1 watermain break repairs.

Discharges of flushed water are also regulated under Condition 4. All samples shall be considered distribution samples, taken and tested in accordance with O. Share facebook twitter Print.

Chain of custody Date and time of return to normal service Water Advisory declared: Flow may be discontinued after an Air gap has been created.

Flushing shall continue until the discharged water is free from discoloration, and secondary disinfection has been restored as per 3.

For planned swabbing and hydraulic e. Where copper pipe is used for smaller diameter watermains, Table 1 does not apply.

Watermain disinfection procedure |

Appendix D The following flowchart is an example of the typical steps required for Category 2 watermain breaks. Refer to Appendices A and B for a sandard and pictures to better understand the criteria to determine the categories of watermain breaks. Follow the steps described in section 3. The operating authority will attempt to maintain flow from the break, where possible, until an Air gap is established. The following steps must be performed for all emergency watermain repairs Category 1 and Category 2.

The sampling will typically occur at the point of Flushing, and may take place from sampling ports, hydrants, blow-offs, or premise plumbing. The operating authority shall determine if flow can be maintained to the break site until the watermain is excavated.