A major sewer pipeline project set to begin next month is expected to impact traffic in parts of Dublin and Pleasanton through October and improve sewer service in south San Ramon upon completion.
This summer, Dublin San Ramon Services District will rehabilitate 8,000 feet of the Dublin trunk sewer, a reinforced concrete pipe 33 to 42 inches in diameter that carries sewage from smaller sanitary sewer mains in west Dublin and south San Ramon to the wastewater treatment plant in Pleasanton.
Sulfides in wastewater have caused significant corrosion to the interior of the 57-year-old pipe, exposing reinforcing steel in some spots, according to DSRSD officials.
A smaller, shorter pipeline used to process wastewater at the plant will also be rehabilitated.
"(The trunk sewer) has been a vital piece of our community's infrastructure for more than 50 years," DSRSD board president Richard Halket stated. "By investing in a well-planned, efficient rehabilitation project now, we extend its life by another 50 years and minimize the risk of a pipe failure down the road."
Because the pipe runs through a busy commercial area, the agency opted to fix it rather than replace it.
DSRSD's board last week awarded a $5.5 million construction contract to Insituform Technologies to do the work. The board also approved a $376,000 agreement with The Covello Group to manage construction, conduct inspections, and review materials and equipment for conformance with project specifications.
The project's total cost is $6.7 million, paid for with sewer charges.
Construction on the southbound side of Village Parkway between Tamarack Drive and Interstate 580 in Dublin will start in June and finish by mid-August, DSRSD officials say. Work south of I-580, which will affect one commercial parking lot on the north side of Commerce Circle in Pleasanton, is scheduled to start in August and be completed in October.
As part of the work, the contractor will first install a temporary bypass line that will be pressurized by pumps to keep sewage flowing to the treatment plant.
Then they will insert a flexible liner into the old pipe through existing manholes one section at a time. The liner, known as a cured-in-place pipe, will harden to form a smooth surface that will restore the trunk sewer's interior to near-new condition. After that, the contractor will remove the temporary line and repair the affected pavement.
The contractor will work during the daytime in residential areas to minimize nighttime noise. In commercial areas, they will work around the clock. Work that blocks driveways and major intersections will be done at night to minimize traffic impacts.
Whenever the bypass line is operating, a person will be on-site to monitor it, according to DSRSD.
Once construction starts, DSRSD will post updates on its website, as well as on Twitter and Nextdoor.
For more information visit the agency's website or direct specific questions to the project manager by calling 875-2258.