Installation of sewer lining begins
Wednesday, October 13, 2010
The process of lining some of California's sewers began last week in the vicinity of Cedar Street and the Marshall subdivision.
According to Kyle Wirts, about 20,000 linear feet will eventually be lined over a period of several months. Lining the sewer lines with a polystyrene material is expected to reduce leaks, both in and out of the lines. One of the problems encountered by the staff at the south treatment plant has been large amounts of rainwater making its way into the city sewer lines and increasing the flow of water to the plant.
Repairs were made to the sewer system at several points before the lines could be lined. In several of those places, the old clay tile lines had shifted making it impossible to install the lining.
The lining is a polystyrene material delivered in a refrigerated truck, since the material must be kept cold before use, preferably 20 degrees Fahrenheit or colder. It hardens when allowed to get warm.
According to Walden Associated Technologies CIPP Supervisor Brad Rae, the material is delivered to the site inside out, then is inserted into the cleaned line by putting air in it and unrolling it inside the sewer line like a sock, with the original outside becoming the inside. After it is inserted, air is pumped in to press it against the sewer line walls. The material is cured by blowing steam in and keeping it at least 145 degrees Fahrenheit. An hour of cooking it with steam followed by an hour of blowing air in to cool it hardens it into a plastic pipe inside the old pipe.
A robotic camera cutter is sent into the new line to cut the holes for the service laterals to the homes and businesses