Maine Moves Ahead On CSO Projects

Lewiston's Most Difficult Job Faced Multiple Problems
January 2014, Vol. 69 No. 1

The Gendron crew had to go under the 60-inch sewer with the new 48-inch pipe but the old pipe was leaking badly and they didn't want to dig underneath it until it was rehabilitated. "What I saw was not one of the things that I wanted to be playing with," emphasized Gendron. “The city called in the Ted Berry Company to slipline the 60-inch sewer. We worked with them, cutting through the concrete and later doing the laterals with InsertaTee connectors."

The unexpected repair to the old concrete pipe sewer line was declared an emergency. "Within 72-hours from the time it was discovered we got the call, we were putting pipe in," said Matt Timberlake of the Ted Berry Company, Livermore, ME. "Everything had to happen quickly. We've done a lot of work with the city with similar jobs and so they had a high level of comfort that we could design/build the project on the fly with some unknowns, yet go in confident that we would be able to stick to a budget, stick to a timeline and give them what they were looking for. They could have dug it up and replaced it. Or do a cured-in-place liner which is not something that you're going to turn around in 72-hours."

Process

A total of 400-feet of SaniTite HP, 48-inch diameter pipe was sliplined into the old concrete pipe with connections to 10 service laterals, including two 18-inch service lines using Inserta-Tee connections. Its triple-wall profile design reduces friction and along with its engineered bell and spigot joint allows for longer, uninterrupted pushing distances with lighter construction equipment.

"We saw an area where it would be reasonable to put in an insertion pit," explained Timberlake. "We would insert the pipe upstream and terminate into a manhole that was in the middle of a very busy street and then slipline downstream and we connected in the middle.

"We were able to insert in two different directions from one pit and then bring those pipe sections together with a final connection in that pit. We essentially lined upstream into a manhole and then downstream into a manhole. The pit was about 30-feet long by about 12-feet wide at the bottom so that we could use the 20-foot SaniTite HP pipe to minimize joints.”

The upstream manhole was in the middle of one of the busiest streets in the city with a number of pipes that came together into that up-steam structure that could not be disturbed. The Ted Berry Company crew pushed the pipe into that manhole and under the busy street.