Located in a residential neighborhood in Catawba Island, Ottawa County received complaints about foul odors coming from PS 50. Residents wanted the county to provide a sustainable solution that would get rid of the smell for good.

Waterways like riverbeds are naturally cleaned by microorganisms that are attached to rocks and sands  primarily within their pore structures underwater. These microorganisms consume dissolved biowaste (BOD) in the waterbody to clean the water.

IMET technology mimics nature’s way of treating wastewater through its patented aerobic packed bed treatment module design. “We essentially took the riverbed and brought it to the pump station,” said Kaan Gencer, chief operating officer (COO) for IMET.

Before installing the IMET system at PS 50, the pump station wet well produced  H2S, a gas known for its distinctive rotten egg smell. Installing two large IMET Modules into the wet well converted the pump station into a nearly 100% aerobic system, enabling aerobic microorganisms to thrive and causing anaerobic microorganisms to go dormant.

“We converted the PS 50 pump station into an aerobic system,” said Gencer. “We now have enough sustained dissolved oxygen in the water to maintain a high population of diverse aerobic microorganisms at all times.”

Each 14- by 40-inch IMET Module circulates wastewater through its high surface media (an area about half the size of a football field) via an air diffuser at the bottom. The diverse populations of aerobic microorganisms growing within the multi-media are constantly in contact with the dissolved nutrients in the pump station

One year after installing the IMET system, the results have been described as “a game-changer”. Installation of the IMET system resulted in the elimination of the organic mat including considerable amounts of Fats, Oils and Grease (FOG) within the pump station. In this specific application, another noteworthy result has been 80 to 95% reduction of CBOD5 in the wet well depending on the fluctuating residence time due to Catawba’s seasonal population changes.

There are no H2S odor complaints from the local residents and the organic mat has disappeared from the wet well without requiring pump outs. 

The significant chemical savings realized together with other benefits of the IMET system, Ottawa County is setting its sights even higher.

“We feel the installation of the IMET system has been a positive outcome for us” said Christopher Goetz, Water Reclamation Superintendent for Ottawa County Sanitary Engineering Department. “We are hoping that we can reduce even more or eliminate the need for calcium nitrate altogether.”

Looking ahead, Ottawa County plans to implement more IMET systems in other pump stations across the county.

The IMET system reduces H2S production to near elimination by sustaining an aerobic environment and significantly enhancing the oxidation of dissolved sulfurous compounds in the wet well as it maintains dissolved oxygen levels greater than or equal to 3 parts per million (ppm).  In some challenging cases the periodic inoculation of sulfur oxidizing bacteria within the IMET module(s) is added as part of the IMET system.

IMET’s technology pre-treats wastewater by creating a significantly efficient aerobic environment with extremely high population of diverse microorganisms within the wet well.  In doing so, the IMET system also continually seeds the wet well and downstream lines delivering further BOD reduction before the treatment plant.

The IMET System significantly reduces FOG buildup within the wet well and in the downstream lines through efficient bio degradation of FOG. The result is a reduction in the need for pumping the wet well and jetting downstream lines.

The IMET system requires minimal power to operate i.e. each module uses between 200 to 450 watts. A typical pump station requires 1 to 4 IMET modules depending on the size of the wet well.