Consultants tell trustees they are not convinced innovative treatment process would reduce expenses
Village of Fredonia officials know they need to increase the sludge storage capacity at the community’s wastewater treatment plant, but they continue to wrestle with the most cost-efficient way to address the issue.
Sludge is the biosolid by-product collected after wastewater is cycled through the treatment plant.
After being alerted to the problem, officials were concerned to learn the projected cost for a second sludge storage tank had doubled to roughly $1 million.
That triggered research and a contact with Aquarius Technologies, a Port Washington company that has developed a process that dramatically minimizes the amount of sludge generated through the sewage treatment process.
According to the company, the aerobic treatment process uses sheets of a fixed film covered with bacteria-eating organisms.
“We were intrigued with the idea that the Aquarius system might eliminate the need for a second tank,” Public Works Director Roger Strohm told the Village Board at its Sept. 1 meeting.
To determine if the alternative process would make sense for Fredonia, the village hired the engineering firm Strand Associates to compare the cost of the Aquarius systems with the cost of installing a new sludge tank.
Although the Aquarius technology is relatively new in the United States, Phil Bdzusek of Strand said he and village officials were able to tour a plant using the system operated by the Northern Moraine Utility Commission in Glenbeulah.
According to that utility, it reduced the volume of sludge collected at its plant by 68%.
Technical reports were also reviewed from treatment plants in Nebraska and Georgia that use the fixed film technology.
“The folks at Glenbeulah said converting to the Aquarius system was generally a very positive experience,” Bdzusek said.
He said the consultants were unable to collect enough data to document the effectiveness of the Aquarius system in sludge reduction, something that would require data from before and after the fixed film process was put in place.
Aquarius representatives who also attended the board meeting said they would provide whatever comparative data the consultants needed.
However, Bdzusek said even without that additional data, the consultants felt it would not be economically feasible to incorporate the new system in the village.
Although the Strand report said the fixed film system “performs well and produces quality effluent,” it might not be as efficient in the village, adding the needed equipment would limit the plant’s operational flexibility.
Perhaps more importantly, the Strand analysis said incorporating the Aquarius system at the village plant would push the probable cost for upgrades at the treatment plant to $5.5 million.
Alternatively, relying on the extended aeration system with added sludge storage, would cost an estimated $3.9 million.
“We don’t see huge amounts if any savings by going with this system,” Bdzusek said.
“If you needed to replace the existing screen, it might be more cost competitive. But at this point, it doesn’t seem like the right fit.”
No matter what process the village chooses, Village President Don Dohrwardt said officials need to think of the impact on sewer customers.
“This has to come out of sewer user fees. There is no levy involved,” Dohrwardt said.
“A small difference can add up to a big number on the sewer bill. Getting the money from the rate payers is the hard part.”
He said additional research would be done before a final recommendation is made on the treatment plant upgrades.