Environmental Services will repair 40 feet of public sewer pipes and replace two manholes in NE Argyle Drive east of NE 11th Avenue. The pipes and concrete manhole are severely deteriorated from sanitary sewer flows and sewer gases. This project will line the pipes and install two corrosion-resistant manholes. These improvements will help protect public health, water quality, and the Columbia Slough Watershed.
The map below illustrates where sewer repairs will be constructed.
Construction is anticipated to begin as early as July and be completed by the end of December 2018. Once construction begins, work is expected to take about one month to complete.
Work will occur 7 a.m. to 6 p.m. Monday through Friday, and the same hours on Saturday as needed.
The specific dates for this project will be determined after a city contractor is hired to do the work.
This project will use both trenchless and open-cut trench construction methods to repair the sewer pipes and replace the manholes.
To repair the sewer pipes, the city will employ a method called cured-in-place-pipe lining (CIPP). Work crews access the sewer from manholes to insert a flexible liner inside the old pipe. Ultraviolet rays will cure the liner, which gradually hardens to form a rigid, smooth surface that seals cracks and restores the pipe to near-new condition.
This method of using ultraviolet rays to cure the liner does not have the odor typically associated with CIPP lining work that uses water or steam to cure the liner.
CIPP is generally a three-day process to set up the bypass service, line the pipe, and reinstate the sewer connections to buildings.
It might also be necessary for crews to do a small spot repair to a section of sewer pipe that is approximately 15 feet deep and directly underneath a 66-inch pipe that carries just stormwater. Avoiding digging here is the preferred solution, but if the lining operation is not effective at this point in the pipe, crews will have to dig a trench to replace this five-foot section of sewer pipe.
Crews will replace the two deteriorated manholes with corrosion-resistant manholes. It will be necessary to dig a pit to install each manhole.
Permanent pavement restoration will be made after the pipe and manhole improvements are constructed.
This project will require temporary traffic diversion during construction. Access to driveways and properties will be provided at all times, although there may be delays. The goal will be to maintain a 12-foot-wide traffic lane with two-way traffic controlled by two flaggers, one at each end, during work hours.