DNR investigates fish kill resulting from yeast spill at Aveka Nutra Processing, pump failure at Waukon wastewater treatment plant

The Iowa Department of Natural Resources (DNR) investigated and continues to assess a fish kill in a tributary of Paint Creek south of Waukon which was found to be the result of a pair of incidents that took place in succession Monday, July 20, according to an initial media release from the DNR.

Shortly after 11 a.m. that Monday, operators at the City of Waukon Wastewater Treatment Plant on the southeast edge of Waukon reported to the DNR that Aveka Nutra Processing in north Waukon spilled approximately 76,000 pounds of yeast, which was running into the treatment plant through the City’s sanitary sewer system. Normally, the treatment plant routes such spills into a lagoon before being treated in the plant.

However, the City of Waukon reported that the lagoon pump at its treatment facility failed after a power loss, allowing the yeast to spill into the creek and causing a fish kill. Treatment plant operators were able to reroute the yeast to the plant by 11:45 a.m. The DNR media release further explained that the influx of yeast further overwhelmed the treatment plant’s capacity, causing an ongoing release of partially treated wastewater.

City of Waukon Water and Sewer Superintendent Jim Cooper said efforts to determine whether the pump failure was the result of an electrical surge or something brought through the sewer line and plugging up the pump have not produced any evidence of either at this point, noting that there was a control box at the treatment facility lagoon that was without power. “We had a local electrician trace it out and found that it had also blown a breaker in our generator room,” Cooper explained. “The pump is hard wired to a generator, but to my understanding the generator still could have started but no power would have been able to route to the lagoon.”

Cooper said after power was restored, his crew pumped the lift station completely out and inspected it for something that may have been caught in the lagoon pumps and couldn’t find anything. He said they then filled the station back up and made sure that the pumps were working properly, which they were.

Jessica Ragsdale, Environmental Specialist with the DNR Field Office in Manchester, said that she had initially been in almost daily contact with treatment plant operators last week in regard to the discharge, noting that the discharge of partially treated wastewater finally came to an end overnight Wednesday, July 22 into Thursday, July 23.

Ragsdale said she will continue to further assess the stream immediately impacted by the discharge, planning to make a site visit to the location Tuesday afternoon, July 28.

Despite the cloudy water from the spill discharge, DNR fisheries staff members were able to conduct an initial fish count the Monday of the spill. Ragsdale said Fisheries Biologists with the DNR initially reported a small number of smaller non-game fish, such as creek chubs, stone rollers and dace, were casualties of the initial discharge, although she said an exact number has not been reported to her as of yet since the assessment is ongoing.

DNR officials initially recommended preventing livestock and pets from drinking from the creek for three days following the spill or until the water clears up. The DNR will continue to monitor the situation and consider appropriate enforcement action, which Ragsdale said has not been determined at this point but would likely be levied against the City of Waukon since the discharge into the creek can be directly linked to the lagoon pump failure. Without the extent of any DNR enforcement action being known at this point, City of Waukon officials have yet to determine any further action they may take in the matter as well.

John Anderson, general manager of the Aveka Nutra Processing facility in Waukon and Cresco Food Technologies in Cresco, said the spill at the Aveka facility was the result of a procedural problem involving an employee who was unloading the yeast from a truck. He said that procedural matter is being addressed by the company and that a follow-up meeting with City of Waukon officials in regard to procedural and safety standards is being held this Thursday.

“It seemed to be a pair of unfortunate issues happening at the same time, and we are addressing our part in the matter,” Anderson said. “It will certainly be a financial hit for us, and we obviously don’t want to cause any difficulties with the City or the DNR.”

Water and Sewer Superintendent Cooper further discussed the matter at the Monday evening, July 20 Waukon City Council meeting, noting that the DNR was satisfied with how the overall matter was handled under the circumstances but will continue to monitor the situation. Aveka Maintenance Supervisor Matt Pladsen initially addressed the matter with the council that same night as to how the company will approach any training issues to prevent any future occurrences.