Agenda - Public Works Committee - 07/20/2010

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CASE # 4 DISCUSS USE OF PLASTIC PIPE FOR WATER SERVICE LINES By: Tim Himmer, City Engineer Background: A local builder has requested on numerous occasions that staff allow the use of polyethylene (PE) pipe for water services to residential homes in the City. Staff has continually denied such a request due to concerns associated with locating this material and thawing it should it become frozen. This item was discussed by the PW Committee on May 18, 2010, but due to a mix-up the builder and pipe representative were unaware of the meeting and would now like an opportunity to address the Committee and provide their input on the previous discussion. Current City policy only allows for the use of copper (for single family residential properties) and ductile iron (for commercial and multi-family properties) for water services from the main to the meter. Once inside the home, on the opposite side of the water meter, it is up to the builder, the Building Official, and State Building Code to determine the appropriate material. Observations: Since it is the City's responsibility to locate all public utilities outside of a structure it is imperative that we are able to locate these facilities quickly, and utilizing metal pipe that can be located via conductivity allows for this to happen most efficiently. The proposed PE product does include a tracer wire but it is only adhered to the pipe material by tape and staff does not feel that is an appropriate material for long term viability, not to mention the concerns associated with installation and potential damage. This taped tracer wire must also daylight in some location so that the PE pipe can be located via conductivity but a wire left exposed in someone's yard or residence would most likely be clipped and/or lost, and access would also be an issue. In short, it would require additional work on the part of staff to now have another piece of equipment to locate and/or maintain to ensure our ability to locate these buried pipes. Another concern of staff is with the thawing of pipes should the service become frozen. With metal pipes equipment could be set up outside of the home to electrically thaw the frozen pipe from the outside in. With the PE pipe you would have to access the line from inside the residence and use pressurized steam to thaw the line. Doing this would be a messy process in that whatever is used to thaw the line would drain directly back into the home or into the City main. Funding: There is no funding associated with this request, it is strictly for discussion purposes only. Recommendation: Staffs stance has not changed on this matter but, consistent with the PW Committee and City Council direction, we will continue to evaluate new products and ides as they become available. Attachments: May 18, 2010 Public Works Committee minutes Reviewed by: Public Works Director/Principal Engineer PW: 7/20/10