Ischua Creek water quality has improved since fish die-off a year ago tied to Great Lakes Cheese

By RICK MILLER

Olean Star

FRANKLINVILLE — It was one year ago that the state Department of Environmental Conservation received reports of a large fish and wildlife die-off in Ischua Creek.

Large and small fish floated in the creek and lined the shore.

The investigation that followed involving DEC and the state Department of Health pointed to a discharge from the Great Lakes Cheese plant on Route 16 in Franklinville as the responsible party.

Health Department sampling of area water wells showed no signs of contamination from the Great Lakes Cheese discharge.

Great Lakes Cheese has a DEC permit to discharge up to 900,000 gallons of treated water a day into Ischua Creek. A failure of the treatment system led to the toxic discharge that consumed oxygen from the water, according to DEC..

In March, DEC ordered Great Lakes Cheese to pay $475,000 and take corrective action to restore the once pristine trout stream. The penalty includes a $150,000 environmental benefit project for the community.

The cheese plant was forced to cease operations for six weeks, diverting millions of gallons of milk a day to other milk plants until the wastewater treatment system was fixed. 

A local group, Ischua Creek Water Keeper, feels DEC has not provided enough information. The group has used the Freedom of Information Law to FOIL information about the spill and what is being done so it doesn’t happen again. The group hasn’t shared the data it received from its FOILs.

Meanwhile, the Olean Star spotted minnows in the creek from the Elm Street bridge last Monday, a sign that the water quality has improved in the past year.

“DEC’s investigation of the incident revealed that unexpectedly high influent loadings that exceeded Great Lake Cheese’s wastewater treatment plant’s design capacity disrupted the wastewater treatment system in July and August 2025” according to a DEC statement emailed to the Olean Star in response to a list of questions on the Ischua Creek fish and wildlife die-off.”

The statement continues:

“These upsets, which were not properly reported to DEC by Great Lakes Cheese, resulted in a loss of treatment at the wastewater treatment plant, and ultimate failure of the treatment system. That total treatment system failure caused a significant amount of untreated wastewater to suddenly discharge into Ischua Creek. Water quality monitoring results indicated that low dissolved oxygen levels in Ischua Creek and total nitrite and total ammonia contributed to the fish die-off.” 

“Since that time, DEC staff in multiple programs have been fully engaged in documenting the full extent of impacts at the site, monitoring current water quality and environmental conditions, ensuring ongoing compliance with the Order on Consent and all current permits issued to Great Lakes Cheese. Water quality monitoring results obtained after the August 2025 discharge demonstrate that water quality has improved throughout Ischua Creek. See DEC’s webpage for the monitoring data”.

“In October 2025, DEC entered into an Order on Consent with Great Lakes Cheese. DEC’s order required Great Lakes Cheese to complete extensive corrective actions to address the violations, including detailed in-stream monitoring at the facility’s wastewater treatment plant operations; modifications to the wastewater treatment plant; implementation of plans to timely detect plant upsets to prevent a recurrence of the August 2025 discharge; actions to abate hydrogen sulfide exceedances from reoccurring; and the hiring of independent third parties approved by DEC to further ensure compliance with the terms of the Order; and timely reporting of sampling data.

“The exceedances of Great Lake Cheese’s State Pollutant Discharge Elimination System (SPDES)  permit that occurred prior to the August 26, 2025 discharge, as noted in the July 10, 2025 Notice of Violation (NOV), did not result in the fish die-off.  DEC staff conducted a routine fish and wildlife survey in July 2025 in Ischua Creek, independent of the NOV, approximately 7.5 miles south of the facility.  Staff observed many healthy fish species and other aquatic life; no dead or dying fish were observed during that survey. DEC’s investigation of the incident revealed that unexpectedly high influent loadings that exceeded Great Lake Cheese’s wastewater treatment plant’s design capacity disrupted the wastewater treatment system in July and August 2025.  

“Great Lakes Cheese has been in compliance with the terms and condition of the SPDES permit and the Order on Consent since they resumed discharge to Ishua Creek in October 2025.  In addition to requiring the performance of significant corrective actions, part of DEC’s order requires the timely reporting of sampling data and hiring of independent third-parties to ensure compliance with the terms of the order and applicable environmental laws and permits issued to GLC.

“DEC also intends to pursue a Natural Resources Damage claim against Great Lakes Cheese to ensure restoration of the impacted section of the Creek.”