MARIETTA - A Columbus-based company will perform a several-months study of the 20 miles of sanitary sewer lines on the west end of Marietta, according to the chairman of city council's water, sewer and sanitation committee.
"We've had some problems with the sewage collection system on the west side, so we hired a company to look for groundwater infiltration into the sanitary sewer system," said Councilman Mike McCauley, D-2nd Ward.
He said URS Corp., a Columbus firm, was chosen for the job out of six or seven companies that responded to the request for qualifications. The contract will be for $96,300.
"They'll put flow meters and rain gauges on the west side sewer lines to check for groundwater leaking into the sanitary sewer system," McCauley said. "Our Harmar lift station is pumping way too much through the sewer line that runs under the (Muskingum River) and on to the wastewater plant, especially during heavy rains. We're also seeing some backed-up sewage in the west end."
He said the problem is either being caused by groundwater infiltration or there may be a clog in the system.
"It's also important to get this taken care of now because in a couple of years the city will be taking on sewerage from the Oak Grove area and the Gilman and Harmar lift stations will have to be able to handle that additional flow," McCauley said.
The URS study, which will begin this month, is the first phase of a project that will culminate in the replacement of the Harmar lift station. McCauley said the total project cost could be around $250,000.
Councilman Tom Vukovic, D-4th Ward, who represents the city's west end, noted the city just recently completed an upgrade of the lift station along Gilman Avenue.
"The flow from Oak Grove will eventually come through there," he said. "And the only line crossing the river from that area is through the Harmar lift station."
Earlier this year city wastewater superintendent Steve Elliott said improvements are needed and planned for the pumps and lift stations that are part of the west side system, but it would not make sense to spend money on those upgrades without first determining what's causing system backups and overflows.
He said there are improvements being planned for lift stations and pumps in the west side system, but a "choke point" exists somewhere in the system that causes sanitary sewer overflows during periods of heavy rain.
Elliott said the 1,350-foot, 10-inch diameter sewer main that carries sewerage under the Muskingum to the east side of the river and on to the wastewater treatment plant could be part of the problem, but a study would be needed to verify whether that's an issue.
He said about 200,000 gallons of wastewater a day pass through the west side system.
When the Oak Grove area is tied into the city's system, the volume is expected to double to 400,000 gallons a day.