Saline City Council will approve a plan to borrow up to $4 million to deal with the odor issue at its aging wastewater treatment plant. Council came to unanimous consensus after reviewing a the wastewater treatment plant odor study final report and recommendations which were presented by Webster Environmental Associates.
Council accepted WEA’s recommendation to demolish the existing odor scrubbers and install a carbon adsorber to treat air from the city’s rotating biological contactors and septage receiving building at the plant. A new bioscrubber will be installed at the plant. The plan also calls for more efficient covers on tanks and channels at the facility, new ductwork to route foul air into the new systems and a carbon adsorption odor control system at the southside pump station to treat foul air from the wet well. The recommendations were also favored by WWTP superintendent Bob Scull and TetraTech, the company that managed the most recent WWTP project.
City council is also in favor of using the state’s revolving loan option instead of going to the open market for the money. Using the state option is expected to save about $400,000 but add about eight weeks to the project timeline. The project is expected to eliminate 99 percent of the odor that escapes the issue.
After the presentation of the study, Mayor Brian Marl read a prepared statement emphasizing the city’s commitment to tackling the issue.
“Pungent and infrequent odors have been an issue in this community for a number of decades. However the frequency and severity of the odors permeating from the wastewater treatment plant of late are unacceptable and have an adverse impact on our citizens’ quality of life,” Marl said. “The current situation will not be tolerated. I regret this approach took several months, but the best solutions are data-driven. This manner of doing business almost always produces the best results.”
In the past the city over-promised and under-delivered on this issue, Marl said, and he hoped city’s action would finally remedy the issue.
Jim Ross, Project Manager for WEA, presented the results of the odor study to council. The first study was conducted in December and the second in July. Ross expected the July study would show more odor and more issues, due to the temperature of the wastewater. But the results were much worse than expected. In some cases, the hydrogen sulfide readings were more than 10 times higher than they were in December. Ross couldn’t explain the extreme variation, but the summer readings were helpful and changed the ultimate recommendations.
He presented several conclusions. Among them:
- The 20-year-old Duall chemical scrubber was found to be a significant contributor to the off-site odor emissions. A second chemical scrubber is working fine but is 17 years old, nearing the end of its expected lifetime, and the manufacturer is out of business.
- The headworks facility was a source of odors.
- Odor leaks from sludge holding tanks.
- The city’s acceptance of septage (from local farmers) can cause elevated odor levels while the septage is being unloaded.
WEA presented six alternatives, ranging from $2.2-3.2M. The six alternative, which council chose, showed the best odor control and costs $2.89 million. According to maps provided by WEA, at its peak, the odor will only be detected across Monroe Street and as far east as Mark Hannah Court or Crestwood Circle.
Council wrestled with a decision on financing and timing. At several points this year, council indicated the city should consider borrowing on the open market if it resulted in speeding the project along. But council learned Monday that going the open-market route might allow the city to shave seven or eight weeks from the project timeline. Using the state’s revolving loan program, while a bit more cumbersome and slow, will save the city about $400,000.
The state’s revolving loan program releases funds during several windows throughout the year. Councillors asked if it was possible to speed the design process and make an earlier window. Such a request would require design and engineering to be done by November, which would be a “Herculean task,” according to Brian Ruble, of TetraTech, which will manage the project. Later, pressed by Councillor Dean Girbach, Ruble elaborated.
“Given the importance of this project, we need to get it right, so that you have a system that works properly for the next 20 years,” Ruble said.
While council took steps to address the odor problem, several council members had questions about short-term solutions and big-picture issues.
“For the next two years residents will have to smell sewage. We’ve got to make it priority to find some kind of interim fix. It’s not fair to residents of the town,” Dillon said. “You cannot sit in a downtown restaurant without smelling it.”
Councillor Dean Girbach asked whether the city might consider using funds from the Zippy Car Wash land sale to start the project early.
Wastewater Treatment Plant superintendent Bob Scull indicated that efforts to repair and use the malfunctioning Duall scrubber might actually make the problem worse. Mayor Brian Marl agreed and advised taking the scrubber offline.
The big-picture issue is tough to ignore as council bounces from big issue to big issue. Last week, the big issue was Andelina Farms and the seemingly unaffordable cost of expanding the city’s water and wastewater utilities.
Councillor Dillon said she would hate to sink money into repairing the wastewater treatment plant only to find out in two years or five years that the facility doesn’t meet the city’s needs.
City Manager Todd Campbell said he agreed. Campbell said the city has potential developments to the west and north of the city that might require utilities. Currently, the WWTP is operating at 66 percent capacity. If the number rises to 85 percent, the city would be required to submit a plan to the DEQ for addressing growth.
“I wish my crystal ball worked, but it doesn’t,” Campbell said. “It’s difficult to forecast. Whether that’s in a year or 10 years, I don’t know.”
Ruble told council that project being discussed would serve the WWTP to its capacity.
Council will take up a motion on the issue at its meeting Sept. 11.
Longtime Saline residents Jim and Joan Roth were the only people to speak to the issue during public comment. The Roths live 150 feet away from the plant on Annwood Court. Joan Roth said intermittent odor issues have always been an issue. But the problem has become more frequent and severe since the plant was renovated three years ago.
"The odor now permeates our home with the windows closed," Joan Roth said. "We pay high taxes for a 1,000-square-foot home. I request a solution be acted on now and a contract be awarded to a company with expertise. I want to be proud of the town I love."