Sewer plant sniffs out 'cannibal' system

AMERICAN FORK — Hungry microorganisms that like to eat excrement — and each other— could be a key to solving the Timpanogos Special Services District's odor issues.

Board members of the district are considering using a "cannibal" system of waste treatment that could potentially cut 80 percent of the solids the sewage plant handles. Decreasing the waste so significantly should also diminish odors associated with the district.

"As far as capacity issues and odor issues, we're trying to have everything designed, constructed and on-line within three years, which is quite aggressive," Timpanogos Special Services District manager Garland Mayne said.

The district recently came under fire from nearby businesses for the pungent smell that regularly wafts their way.

In response to complaints made by Pleasant Grove's mayor, as well as several businesses near the plant, which is just off of exit 275 on I-15, the board began examining alternatives to processing incoming waste.

So far, members of the board have visited one cannibal system in California and another in Indiana to educate themselves about the proposed system's benefits.

If the district chooses to adopt the new system, it would technically be the largest cannibal-type system in the United States to date, Mayne said.

Just how much the new system would cost is still in question. The district may only change half of the plant to facilitate a cannibal system and leave the other half the same, which would affect the price.

In order to pay for an expansion, odor-control measures and a new solids handling process, the district has proposed an $85 million bond.

Fortunately, the district's system, as it is, is compatible to converting to a cannibal system, Mayne said.

Currently, the district's solids are received into oxidation ditches. The ditches have microorganisms that eat the solids, then settle to the bottom of the substance. The substance then goes on for further treatment before being composted with green waste.

Most of the smell of the plant comes from the composting process, district engineer Larry Bowen said. That means the district either needs to find a way to compost off-site, away from the businesses that have located nearby, or decrease the waste once it comes in.

In the cannibal process, a second "ditch" with a different kind of organism is added to the first. As the waste moves from the first ditch to the second, and back to the first again, the microorganisms eat each other.