Fans in the bar screen building blow air into the foul air line.
Dublin San Ramon Services District needs to replace 405 feet of the 42-inch-diameter, corrugated plastic, foul air pipe that runs from the center of the Regional Wastewater Treatment Facility and along I-680 in Pleasanton. The 18-year-old pipe has deteriorated beyond repair.
To perform the replacement, a contractor will remove the old pipe and replace it with a new, 42-inch-diameter, fiberglass-reinforced pipe that pushes foul air to 70 feet of three smaller pipes (24 inches in diameter). From there, the foul air is pushed through 2,350 feet of even smaller pipes (10-inch diameter, perforated pipes) that disperse the air through five feet of special dirt, also known as biofilter beds.
In addition, the construction crew will repair cracks in the holding basin and roadway under which the 42-inch pipe travels.
|Construction crew members work on preparing the basin for concrete installation on July 2.
“While under construction for about a month, we won’t be able to scrub the foul air coming from the bar screens and grit tanks, so we apologize in advance to our neighbors,” says project engineer Rudy Portugal. “However, once construction is completed, we will be able to reduce future odors from our bar screens and grit tanks.”
When the wastewater arrives at the plant, the bar screens (steel bars with quarter-Inch gaps) filter out inorganic objects like pieces of wood, metal, and rags. At the next stage in the process, the grit tanks remove gravel from the process. In both cases, the foul air is sent 405 feet through the pipe and pushed through the biofilter beds, removing odor from the air.
Construction begins mid-April and is expected to last about a month and a half. Total estimated cost of the project is $2.2 million.
Questions regarding the project can be directed to Rudy Portugal, Foul Air Replacement Project engineer, at 925-875-2251 or firstname.lastname@example.org.
View a one-minute time-lapse video of crews pouring concrete for the basin in July 2019: