Grease Interceptor Problem Pushing Pollution Into Michigan

Pollution in the sewer system in Granger Indiana has raised questions about whether businesses are contributing to the problem by disposing food waste without using proper grease interceptors.

An operator for the St. Joseph County Regional Water and Sewer District, which runs the 150-user Granger sewer system, this month will inspect 20 food service establishments to ensure they have appropriate grease interceptors. The establishments include several restaurants, two schools and a supermarket.

District officials believe that food waste, along with grease, is entering the sewer line and creating excessive hydrogen sulfide — a corrosive pollutant that can damage the system.

But officials still don’t know which establishments have grease traps, even though the South Bend-St. Joseph County Building Department required certain ones to install them before the Granger line started operating in 2012 to serve the area’s business district and homes.

“If someone doesn’t maintain their grease interceptor, that’s a problem for us,” said Ken Jones, a technical adviser for the district. “And if there is a lot of food prep waste in some of those facilities, that’s also a problem.”

Until the problem is solved, the pollutant will continue to flow to Michigan’s Ontwa Township, which has an agreement with the district to transport Granger’s wastewater to Elkhart’s treatment plant.

The line runs north from Granger on Bittersweet Trail, crosses the state line and eventually connects to Ontwa’s wastewater system at a discharge point on Michigan 62 to the south of May Street. It then extends to Edwardsburg before eventually reaching Elkhart’s plant.

Ontwa has used chemicals to successfully reduce the pollutant, a byproduct of concentrated organic matter, to safe levels before wastewater reaches Elkhart’s plant.

The district has tried for about two years to reduce the pollution. But it has come at a cost, and there still isn’t a solution in sight.

The district hasn’t yet found a chemical that works well. The Clay Fire Department tried to help last month by pumping water into the line, but the strategy didn’t work.

The district pays Ontwa about 5 cents per 1,000 gallons of wastewater that comes from Granger. It also pays Ontwa to treat Granger’s wastewater with chemicals, and it recently gave the township $11,500 to repair the concrete walls of five manholes that were damaged because of hydrogen sulfide.

The Building Department required food service establishments to have grease interceptors installed before connecting to the system in 2012, but it didn’t use criteria developed by the water and sewer district.

As a result, district officials suspect the Building Department allowed some establishments to have grease traps installed under sinks. They say such traps can still allow grease to pass through and aren’t as effective as external traps installed on service lines outside of establishments.

“Building Department inspections might not have matched up with what we would have wanted,” said Barry Skalski, president of the district’s board. “The department did what they wanted, and they overrode our standards.”

Building Commissioner Chuck Bulot said the department is required to follow the International Plumbing Code to determine whether an establishment needs a grease interceptor.

“Although the district might have their set of rules they want to follow, we can’t have stricter requirements than are required by code,” Bulot said. “We indicate whether a grease trap is needed, but we don’t give a sizing for it. We tell them to follow manufacturer’s recommendations.”

Bulot added that the department doesn’t keep a detailed record of grease traps that are installed.

The St. Joseph County Health Department, meanwhile, is only required by state law to address issues with grease traps of septic systems — not sewer districts, according to Nick Molchan, the department’s administrator.

Jones, the technical advisor, said the district’s connection standards require food service establishments to have external grease interceptors, and he believes they could be compelled to install them. And he said the district could compel establishments to cover the cost of fixing traps that aren’t working.

Earlier this year, the district installed a pair of chemical injection pumps to treat Granger’s wastewater. One was installed in April behind the Martin’s grocery store on Indiana 23, and the other was installed last month along Anderson Road. But those pumps were removed two weeks ago because the strategy wasn’t working.

District officials said they chose the Martin’s location because it was convenient, but they don’t suspect the store, which has a bakery and deli, has any waste disposal issues.

Ted Alwine, Martin’s director of engineering, said in a statement: “Our Granger store has never put ‘food waste’ into the sewer. Since this store was previously on a septic system we have no garbage disposals and even strain out food waste particles at the sinks. Also, we have a large underground grease trap in place which is capturing grease prior to entering the sewer. This too was in place to protect the former septic system.”

Hydrogen sulfide levels in the Granger system have been tested at roughly double the federal limit at the discharge point in Michigan where wastewater enters Ontwa’s system, said John Harsh, Ontwa’s wastewater administrator.

Ontwa previously had levels of pollutants that were worse than what has been found in Granger’s wastewater, but the township fixed the problem by increasing chemical treatment and spending more than $100,000 on equipment. The township had been fined by Elkhart for the problem, which took years to resolve.

Ontwa’s system has PVC pipes that can’t be damaged by hydrogen sulfide, Harsh said, but the pollutant has put its concrete manholes at risk of being damaged. And he said Elkhart’s wastewater plant has concrete pipes that could be damaged.

“I personally think they can get the pollution down using chemicals, but they’re going to have to do some significant homework and put together a technical team,” said Harsh, who is helping with the problem in Granger.

To prevent your grease interceptor from getting clogged with food solids, consider installing The Drain Strainer so you won’t have grease trap pumping issues.