2012-09-25_PWETC_Minutes - Laserfiche WebLink

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6. Watermain Lining Presentation Utility Engineer Khristine Giga provided a presentation specific to several sections of the City's aging water main infrastructure identified for an upcoming rehabilitation project, as detailed in the staff report dated September 25, 2012. Ms. Giga advised that this project is currently being advertised for bids, with those bids to be opened on October 10, 2012, and if those bids are favorable, scheduled for construction in November of this year. Ms. Giga reviewed two (2) new technologies in the industry as viable alternatives to open-cut pipe replacement, and as a way to achieve significant cost-savings while still extending the life of the existing underground pipe system. Ms. Giga reviewed the "cured-in-place-pipe (CIPP) liner, similar to that used on sanitary sewer lining projects; and another lining technology developed by 3M that is a spring-in-place lining system. Ms. Giga reviewed the limited number of manufacturers providing the CIPP lining system (Insituform, Aqua-pipe, and Norditube), with the spray-in-place lining system developed and produced only by 3M. Ms. Giga noted that this new product developed by 3M had not been used for any Minnesota projects to-date, however, it had been used in other states and in Canada and Europe with climates similar to that of MN. Discussion included the process and chemical make-up of the liner materials; interruption time for services; cleaning of the lines before installation of the liner materials; and cure time; with potential to re-establish service connections within the same day. Further discussion included safety concerns, specifically with the new 3M product, and recommendations by staff to provide affected residents with a"boil notice" for their water use until bacteria tests were passed, usually within 24-48 hours. Mr. Schwartz advised that if the 3M product was chosen, staff was recommendation that the City distribute bottled water to the affected properties for consumption purposes. Ms. Giga noted that the American Water Works Association (AWWA) had endorsed the lining products; and the products were accepted by the non-profit organization looking out for environmental and citizen public health and safety concerns, the National Sanitation Foundation (NSF 61) founded in 1944, with the organization having developed American national standards for all materials and products that treat or come into contact with drinking water and now having replaced the former U.S. Environmental Protection Agency (EPA) advisory standards with those of NSF 61. Ms. Giga provided several video clips, excerpting a Discovery channel documentary about"Aqua-pipe" lining; and another clip excerpting the 3M Scotchkote Pipe Renewal Liner 2400. Page 4 of 13