APPENDIX A WATERMAIN TESTING PROCEDURE: NEW DEVELOPMENT

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1 SCOPE This procedure covers the cleaning, disinfection, hydrostatic testing and sampling of watermains. Unless specified otherwise, this procedure applies to all new watermains including above ground by-pass watermains, cement relined watermains, and private watermain systems. DEFINITIONS Town Development Services - shall be the Director of Development Services, or his designate, or an Engineering company retained by the Town. Town Public Works - shall be the Director or Manager of Public Works, or his designate, or an Engineering company retained by the Town. Town Public Works operator - shall be a Town Public Works employee certified under Ontario Regulation 435/93. Development Engineer - shall be Engineering company retained by a Development owner. Development Owner - shall be a company or individual, who has signed the subdivision agreement. Workforce - shall be a Specialized Watermain Disinfection Contractor whose personnel have current MOE licensing, Ontario Regulation 435/93 (Operator 1). Disinfectants - shall be Calcium or Sodium Hypochlorite that meets or exceeds AWWA Standard B300. Neutralizing Agent - shall be Sodium Thiosulfate that meets or exceeds AWWA Standard C651. REFERENCES These procedures are based on, and should be used in conjunction with the Ontario Provincial Specifications (OPS), the American Waterworks Association (AWWA) standards and the Ontario Safe Drinking Water Act (SDWA) 05 Feb 23 1 of 12

2 GENERAL REQUIREMENTS Keep pipes clean and dry. Take precautions to protect the interiors of pipes, fittings, and valves against contamination. Cap all openings with watertight plugs/seals. Remove plugs only when making connections. Complete joints of all pipes in trenches before any stoppage of work, i.e. at the end of the workday. Pipes shall not be laid in water. The new watermain shall be connected to the existing system at a maximum of only one location where there is a suitable isolation valve unless otherwise accepted by Town Public Works. Other required connections to the system shall be stopped short and capped. SUPERVISION, TESTING AND RECORDS The Development Engineer shall witness all cleaning, disinfection, hydrostatic testing and sampling activities. The Workforce, carrying out the cleaning and disinfection in conjunction with the Development Engineer, shall take and record measurements on Town approved forms. All such records shall be submitted to Town Public Works and Town Development Services. ISOLATION VALVE OPERATION A Town Public Works operator shall be on-site to operate valves not fitted with an approved reduced pressure principle backflow preventor. The Development Engineer is to notify Town Public Works, three (3) working days in advance to make arrangements for the operation. FORMS This document to be used in conjunction with the forms entitled: Watermain Disinfection, Pressure Testing & Acceptance, Chlorine Residual, and Form Letter: Watermain Schedule. 05 Feb 23 2 of 12

3 TESTING PROCEDURE Low level chlorine residual shall be tested with an electronic tester such as a Hach Pocket Colourimeter or equivalent. 1. Sample Request Drawings Three (3) sets of Sample Request drawings, prepared by the Development Engineer, shall be submitted to Town Public Works a minimum of two (2) weeks prior to chlorinating. Consideration shall be given to sectioning off areas as required. All new watermains, including all stubs to be tested, shall be highlighted. Supply points shall be indicated. One copy of the Sample Request drawing shall be returned to the Development Engineer. All sample points are to be brought to the surface complete with a valve. Pressure test boundaries are to be the same as the valved off sections of the Sample Request drawings unless otherwise directed by Town Public Works. 2. Loading of Watermain (AWWA C Section Modified) The new watermain shall be loaded via a by-pass installed around the isolation valve. The by-pass shall be used for all water supply unless otherwise noted. The minimum size of by-pass shall be 50 mm diameter, and fitted with an approved reduced pressure principle backflow preventor. All materials for the by-pass are subject to approval by Town Public Works. For details on the installation of the by-pass, see Drawing #WS-602 (attached). The by-pass shall be removed once all testing is completed and accepted. For direct bury installations, the saddles shall be removed and repair clamps installed in their place. For chamber installations, the main stops shall be removed and the by-pass opening sealed in an approved manner. A proposed work schedule shall be submitted a minimum of three (3) working days prior to chlorinating to Town Public Works (see sample attached). 3. Swabbing The watermain shall be loaded prior to the commencement of swabbing. All swabs that are inserted into the watermain and removed, either during construction or after, are to be witnessed and numbered by the Development Engineer. The Development Engineer shall record the number of swabs inserted and retrieved. The watermain shall be swabbed in such a manner that all pipes in the system have been swabbed. All swabs shall be new and sized a minimum of one size larger than the watermain. All stubs shall be provided with a temporary flushing hydrant to allow for the removal of the swabs. The operation of the isolation valve shall be performed by the Town Public Works operator. 05 Feb 23 3 of 12

4 4. Flush to Remove Turbidity (AWWA C Sec OPS ) The watermain shall be flushed to remove any remaining air pockets and foreign matter from the watermain via the by-pass. If this is unsuccessful, the Town Public Works operator shall operate the isolation valve once they have ensured there is flow, via the bypass, to the discharge. The watermain is to be flushed through each hydrant for 5 to 10 minutes until the watermain achieves and sustains a turbidity of less than 1 NTU or at the Town s discretion, no higher than that of the existing distribution system. The locations where turbidity samples are taken shall be indicated on the sample drawing. The turbidity testing shall be performed by the Workforce and recorded by the Development Engineer. 5/6. Disinfecting Watermain (AWWA C Sec OPS ) The method of disinfection to be used is the continuous feed method. The chlorine is to be injected into the system through the by-pass / test point. There shall be no use of the isolation valve during this process. The chlorine solution is to be thoroughly mixed prior to pumping it into the system. The chlorine solution shall be applied so that the chlorine concentration is a minimum of 50 mg/l throughout the system and does not exceed 100 mg/l. The chlorine solution is to be flowed through each hydrant and blowoff. The high chlorine residual is to be measured by the Workforce at each sample location and recorded by the Development Engineer. Once the desired level of chlorine has been achieved, the remaining solution within the tank is to be neutralized and disposed of. The high chlorine shall be isolated in the system for a minimum of twentyfour (24) hours but not exceeding 72 hours. After the required contact time, the chlorine residual shall be taken at each sample location by the workforce and recorded by the Development Engineer. Flow required to take the residuals shall be provided through the by-pass. If the residual is above 50% of the original concentration, the chlorine is ready to be discharged. In the event that the residual is less than 50% of the original concentration of the chlorine, the system shall be discharged, swabbed if necessary and re-chlorinated. 7/8. Removal and Disposal of Super-chlorinated Water (AWWA C Sec. 4.5 OPS ) The watermain shall be flushed to remove super-chlorinated water via the by-pass. If this is unsuccessful, a discharge shall be set up by the Workforce to remove the superchlorinated water prior to the Town Public Works operator opening the isolation valve. The watermain shall be valved in such a manner that the direction of the flow is known to promote the expedient and complete removal of the super-chlorinated water. The superchlorinated water shall be flushed from the main through all hydrants and sample points until the chlorine residual matches that of the existing distribution system (supply location). The chlorine residual shall be checked at each sample point by the Workforce, and recorded by the Development Engineer. Once this is achieved, the system shall be flushed for an additional thirty (30) minutes. 05 Feb 23 4 of 12

5 For the disposal of super-chlorinated water, the Development Engineer shall ensure throughout the disposal process that the chlorine residual in the neutralized water does not exceed mg/l. Super-chlorinated water shall not be discharged to a storm or sanitary sewer or watercourse unless the residual is reduced to this level. Methods of disposal include flushing through a neutralizing dam or flushing to a neutralizing tank. Neutralizing chemicals shall be as per AWWA C651.9 Sec.6 Appendix B. The fresh supply water shall be left isolated within the system for a minimum of twentyfour (24) hours. For above ground by-pass watermains, the isolation period can be shortened to sixteen (16) hours. 9. Initial Bacteriological Sampling (SDWA.) The Town Public Works operator shall ensure the by-pass is open and take a bacteriological sample at each sample location and deliver it to the York Durham lab. The cost of all bacteriological sampling shall be charged back to the Development Owner unless otherwise specified. 10. Sample Results (SDWA.) Typically Town Public Works will receive the sample results, via fax, forty-eight (48) hours after the samples are delivered. Town Public Works shall notify the Development Engineer of the sample results. A hard copy of the sample results will be mailed by the lab to the Town and the Development Engineer. If sample results meet SDWA. and York/Durham laboratory requirements, hydrostatic testing shall commence. If sample results do not meet SDWA. requirements, the failed section must be re-disinfected and resampled at sample locations determined by the Development Engineer and approved by Town Public Works. 11. Flush to Introduce Fresh Water A discharge shall be set up for the removal of the existing water utilizing the by-pass. If this will not provide satisfactory results, the Town Public Works operator shall opening the isolation valve after ensuring that the watermain has been valved in such a manner that the direction of the flow is known and will promote the expedient and complete removal of the existing water. Once the existing water has been removed from within the system and replaced with fresh water, the hydrostatic testing is ready to commence. Note: Items 12 and 15 are not required for above ground by-pass watermains and cement relined watermains 05 Feb 23 5 of 12

6 12. Hydrostatic Testing (A.W.W.A. C Sec 5.2, C Sec 7.3) The watermain shall be pressurized to 1035 kpa (150 p.s.i.) and maintained there for two (2) hours. The test section shall not exceed any of the isolated sections as indicated on the sample drawing. If the test pressure drops significantly, the test section shall be isolated to a manageable area. At the end of the two (2) hour test period, the volume of water used to maintain the 1035 kpa pressure is to be recorded and compared against the allowable leakage. The leakage is to be measured by the Workforce and recorded by the Development Engineer. The allowable leakage is 1.0 L per mm of pipe diameter per km of pipe per day. Allowable Leakage per Hour (L) = 1.0 L*diameter (mm)*length (km) 24 For High Density Polyethylene (H.D.P.E.) pipe, the test section shall not include any other materials. A 3 to 4 hour deformation period, maintaining a 1035kPa pressure, shall be required immediately prior to the hydrostatic testing. If the test is successful, the system shall be left in isolation for 24 hours before taking final samples. If the test is not successful, the leak shall be found, repaired and the hydrostatic test applied again until it is successful. 13. Final Bacteriological Sampling (SDWA.) The Town Public Works operator shall ensure the by-pass is open and take a bacteriological sample at each sample location and deliver it to the York Durham lab. The cost of all bacteriological sampling shall be charged back to the Development Owner unless otherwise specified. 14. Sample Results (SDWA.) Typically Town Public Works will receive the sample results, via fax, forty-eight (48) hours after the samples are delivered. Town Public Works shall notify the Development Engineer of the sample results. A hard copy of the sample results will be mailed by the lab to the Town and the Development Engineer. If sample results are successful, any final connections shall be made, (see the next section). If sample results do not meet S.D.W.A. and York/Durham laboratory requirements, the failed section must be re-disinfected and re-sampled at sample locations determined by the Development Engineer, subject to the approval of Town Public Works. 05 Feb 23 6 of 12

7 15. Final Connections to Existing Mains and Acceptance (AWWA C Sec 4.6) If there are additional connections to be made to the existing system, the work shall be done in accordance with AWWA standards. Water mains and appurtenances must be completely installed, flushed, disinfected, and satisfactory bacteriological sample results received prior to permanent connections being made to the active distribution system. Sanitary construction practices must be followed during installation of the final connection, so that there is no contamination of the new or existing water main with foreign material or groundwater. 1. Connections equal to or less than one pipe length ( 5.5 m). The new pipe, fittings and valve(s) required for the connection may be spray-disinfected or swabbed with a minimum 1-5% solution of chlorine just prior to being installed, if the total length of the connection from the end of a new main to the existing main is equal to or less than 5.5 m. 2. Connections greater than one pipe length (>5.5 m). The pipe required for the connection must be set up aboveground, disinfected, and bacteriological samples taken, if the total length of the connection from the end of a new main to the existing main is greater than 5.5 m. After satisfactory bacteriological sample results have been received for the "predisinfected" pipe, the pipe can be used in connecting the new main to the active distribution system. 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. The disinfection shall be done by the Workforce witnessed by the Development Engineer. The Development Engineer shall also conduct a visual examination of the pressurized system prior to burial to ensure that there are no visible leaks. Once the connection is made, the Town Public Works operator shall sample at the sample location for the watermain section that includes the connection and deliver it to the York Durham lab. The cost of all bacteriological sampling shall be charged back to the Development Owner unless otherwise specified. If sample results do not meet SDWA. and York/Durham laboratory requirements, the failed section must be re-disinfected and re-sampled as determined by the Development Engineer, subject to the approval of Town Public Works. The system shall be put into service once a certified copy of the forms entitled New Watermain Disinfection, Pressure Testing & Acceptance and "Test Results, Chlorine Residual and Turbidity Count" have been received and accepted by Town Public Works. 05 Feb 23 7 of 12

8 16. On-going Maintenance Town Public Works shall ensure that the watermain system remains potable. The Town Public Works operator shall take regular samples to ensure the system meets S.D.W.A. requirements. The cost of all Town activities (including flushing, hydrant maintenance, bacteriological sampling, etc.) shall be charged back to the Development Owner until the subdivision is assumed. 17 Disinfection of By-pass Service Hoses All by-pass services hoses to be used shall be of potable water grade. The following shall be done: Service hoses shall be chlorinated at 25 mg/l using a continuous feed method. Service hoses shall be isolated for a maximum twenty-four (24) hour contact time. Service hoses shall be de-chlorinated, and the residual shall match that of the existing water supply. Service hose service hoses shall be isolated for a minimum twenty-four (24) hour incubation period. Bacteriological samples shall be taken from each hose bundle. Service hoses shall be capped at both ends with brass caps. Service hoses shall not be installed on by-pass piping until the day of the change over from the distribution watermain to the above ground by-pass watermain. 05 Feb 23 8 of 12

9 Date: Subdivision: Workforce: Development Engineer: Witnessed Item Work Description Work Performed By Comments by (initial)* 1. Loading of Watermain Workforce 2. Sample Request Drawings Development Engineer 3. Swabbing Workforce # In # Out 4. Turbidity (< 1 NTU) Workforce/Town Public Works operator 5. Disinfecting Watermain (residual mg/l) Workforce hour Check (residual 50%) Workforce 7. Pre-removal of Super-chlorinated Water Check. 8. Removal and Disposal of Superchlorinated (residual 0.5 mg/l max.) Town Public Works operator Workforce 9. Initial Sample / Sample Results. Town Public Works 10. Introduce Fresh Water Workforce/ Town Public Works operator 11. Hydrostatic Testing Workforce 12. Second Sample / Sample Results. Town Public Works 13. Final connections Workforce/ Development Engineer 14. Post Connection Sample / Sample Results. Town Public Works Please Note: This form to be accompanied by Test Results, Chlorine Residual / Turbidity Counts. Development Engineer s Certification: Firm: We hereby certify that the Workforce carrying out the above mentioned work is licensed by the MOE as an operator and that the watermain has been charged, disinfected and pressure tested in accordance with the procedures as set out herein. Signature Engineers Stamp 05 Feb 23 9 of 12

10 Date: Subdivision: Workforce: Development Engineer: The chlorine residual is to be confirmed with a testing device, litmus paper is not acceptable. The low counts are to be tested with an electronic tester. Location or Sample Number Town Supply Turbidity Count (#3) High Count (#5) 24 hr. Count (#6) Low Count (#8) Development Engineer Signature Engineer's Stamp 05 Feb of 12

11 Form Letter Watermain Schedule Company Name Address City, Prov. POSTAL CODE Date: Project Name: Town File #: Request: We hereby certify that the water system for the above project was constructed as per Town Standards and Specifications and that the watermains are ready to be pressure tested and chlorinated as per Town specifications and criteria. We therefore request the Town to take the water samples at the above project. Site servicing plans previously submitted Schedule: Swab/Turbidity Testing Chlorinate De-chlorine First Sample (min. 24 hrs after de-chlorination) Pressure Test Second Sample (min. 24 hrs after pressure test) Time Date Yours truly, NAME / SIGNATURE / TITLE NAME & STAMP OF P. ENG All requests to be submitted a minimum of three (3) working days prior to scheduled work date and time. 05 Feb of 12

12 DIRECTION OF FLOW REDUCED PRESSURE PRINCIPLE BACK FLOW PRE.VENTOR PLAN SHUT OFF VALVE SADDLE WITH 50mm t.iain STOP (TYPICAL) v._.;,. ; '...;:..., -~- - ~ ~ "..:I :.....:1 ELEVATION NOTES: 1. BY-PASS SHALL BE 50mm DIAMETER 2. FOR DIRECT BURY INSTALLATION, CURB STOPS ARE REQUIRED IN ADDITION TO MAIN STOPS 3. ALL UNITS ARE IN METRES UNLESS OTHERWISE NOTED 05 Feb of 12