On August 26, 2025, the New York State Department of Environmental Conservation (DEC) responded to a report of a significant fish and wildlife die-off along Ischua Creek in Franklinville. DEC’s Division of Law Enforcement began the onsite investigation that afternoon, followed by a full deployment of DEC Division of Fish and Wildlife and Division of Water staff to the initial reporting location and the larger upstream and downstream area.
Governor Kathy Hochul directed a multi-agency response led by DEC and consisting of several major components:
- Coordinating with Department of Health (DOH) and local health agencies to rule out any potential public health exposures;
- Investigating potential impacts to public or private drinking water supplies;
- Issuing a temporary advisory on water-based recreation during the initial investigation;
- Conducting water quality sampling in Ischua Creek to determine the source of the pollution and extent of the water quality problem;
- Identifying the primary source, later identified as Great Lakes Cheese. Great Lakes Cheese is a manufacturer and packager of cheese located in Franklinville, Cattaraugus County.
- Working with Great Lakes Cheese on a temporary pause of operations;
- Deploying on-site monitoring and investigation of facility operations to determine the cause of the discharges impacting fish and wildlife health;
- Investigating and documenting the extensive damages to fish, wildlife, and the Ischua Creek ecosystem;
- Minimizing potential negative economic impacts on workers, farmers, and the local community by working closely with the State Departments of Agriculture and Markets, Labor, and Transportation;
- Actively communicating with local governments, the Seneca Nation of Indians, elected officials, and community members;
- Holding the responsible party accountable for the damages caused; and
- Developing a restoration plan for the affected area.
Water Quality Monitoring
Field teams conducted water quality monitoring to comprehensively evaluate impacts to aquatic life at 10 locations on Ischua and Olean creeks immediately after notification of the fish and wildlife die-off event. Monitoring efforts continued and expanded through August and September, with three additional locations added for evaluation starting on September 11, 2025 (see figure below). Sampling included a combination of in-stream parameters, stream flow, and laboratory water quality parameters summarized in the October 2025 Order on Consent.
Upstream of the Great Lakes Cheese facility, conditions have consistently met State water quality standards. Downstream of Great lakes Cheese, water quality conditions immediately after the reported incident greatly exceeded standards for dissolved oxygen, total ammonia, and total nitrite—factors that are harmful to aquatic life. Since the discharge was halted voluntarily by Great Lakes Cheese on Aug. 29, 2025, water quality has improved throughout Ischua Creek, with dissolved oxygen levels and total ammonia being observed within acceptable ranges since September 8, 2025. Total nitrite collected on September 8 and 17 remained above the water quality standard of 20 micrograms per liter (µg/L) at the three monitoring locations immediately downstream of the Great Lakes Cheese permitted discharge.
Water quality monitoring showed that low dissolved oxygen levels in the creek contributed to the fish and wildlife die-off. This oxygen depletion was caused by organic waste discharged by the Great Lakes Cheese facility. Organic waste is not a chemical or toxin, but in large amounts can create serious environmental problems by consuming oxygen in the water as it breaks down and suffocates aquatic life. Total nitrite and total ammonia levels also contributed to the fish and wildlife die-off. Elevated levels of these parameters can inhibit oxygen transport, damage organs, and cause mortality of aquatic organisms.
Water quality monitoring data can be accessed at the DEC's water quality monitoring ongoing special studies webpage.
In addition to field work along Ischua Creek, DEC staff documented and assessed all operational processes involved at the Great Lakes Cheese facility. DEC teams were on-site to oversee system improvements and monitoring of wastewater treatment plant (WWTP) operations, including:
- Daily technical briefings with Great Lakes Cheese;
- Verifying real-time actions by the company to meet objectives; and
- Walk-throughs of the facility to monitor operations.
Facility State Permits and Registrations
Great Lakes Cheese has a State Pollutant Discharge Elimination System (SPDES) permit number NY0291315 (PDF) that is valid from June 1, 2022, to May 31, 2027.
Great Lakes Cheese also has an Air State Facility (ASF) permit number 9-0499-00108/00007 (PDF) that is valid from May 11, 2022, to May 10, 2027.
Great Lakes Cheese also operates pursuant to petroleum and chemical bulk storage registrations. The petroleum bulk storage (PBS) registration number is 9-601981, it expires on February 9, 2029. The chemical bulk storage (CBS) registration number is 9-000483, it expires on September 6, 2026.
The Great Lakes Cheese facility is located adjacent to a Potential Environmental Justice Area (PEJA) and within a Disadvantaged Community (DAC). Accordingly, all applicable environmental justice and disadvantaged community laws, regulations, and policies continue to be followed.
DEC Enforcement
DEC is committed to holding Great Lakes Cheese responsible for the environmental damage to the creek and working towards a comprehensive restoration plan for this critically important ecosystem. In October 2025, DEC entered into an Order on Consent with Great Lakes Cheese (PDF). DEC will require strict adherence to the schedule of compliance under the Order and continue rigorous oversight of the Great Lakes Cheese facility while required work is performed.
The Order requires Great Lakes Cheese to complete extensive corrective actions to address 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, timely reporting of sampling data, and evaluating the design and operation of the biogas collection and control system to ensure compliance with the company’s Air State Facility permit.
The consent order addresses the numerous violations connected to the Ischua Creek impacts and earlier violations assessed in June and July 2025. DEC required a total civil penalty of $475,000 -- $250,000 paid to DEC and $75,000 suspended pending compliance with the terms and conditions of the Order and an environmental benefit project valued at $150,000. DEC also intends to pursue a Natural Resources Damage claim against Great Lakes Cheese, as warranted, to ensure restoration of the impacted section of Ischua Creek.
Violations of any provision of the Order, or future violations of applicable environmental laws or permits by Great Lakes Cheese will result in further enforcement.
Press Releases
Nov. 21, 2025 DEC and DOH Lift Recreational Use Advisory for Ischua Creek in Cattaraugus County
Oct. 6, 2025 DEC Orders Great Lakes Cheese to Pay $475,000 in Penalties and Take Corrective Actions
Sept. 13, 2025 Statement from NYSDEC Commissioner Amanda Lefton on DEC’s Investigation at Ischua Creek
Sept. 6, 2025 DEC Issues Update on Ischua Creek Water Quality
Aug. 28, 2025 DEC Investigating Environmental Impacts to Ischua Creek in Cattaraugus County
Aug. 28, 2025 DEC and DOH Issue Recreational Use Advisory for Ischua Creek in Cattaraugus County
Contact information
DEC is committed to keeping the community informed about the actions New York State is taking, oversight we are providing, and detailing DEC’s work that ensures public and environmental health is protected in the Ischua Creek area.
DEC will continue to provide updates to the community as additional information becomes available.
The public is encouraged to report unusual fish and wildlife observations in Ischua Creek to (716) 851-7201. For general questions, please email [email protected].
