Northampton's Carlsberg factory has paid out £120,000 to charity after spilling over 400 litres of diesel into the Nene in two separate incidents last year.
The brewery has donated the cash after fire crews were called out to clean up pollution after oil escaped into the river two times in 2017.
The donation comes as part of an 'enforcement undertaking', where firms and individual who have damaged the environment can offer ways to address their offending - including making a payment to charities and projects.
The Carlsberg factory, which sits next to the Nene, was traced as the source of two spills in 2017.
In July 2017, around 230 litres of diesel escaped into the River Nene that was washed out of the factory's drains by heavy rain.
It led to the Environment Agency closing a lock downstream to contain the spill while it was cleaned up.
Then, three months later, an estimated 200 litres of diesel escaped into the same river in a similar way. The diesel took the same path as the previous incident and due to a faulty valve flowed straight into the River Nene.
As a result, Carlsberg has now donated £80,000 to the Wildlife Trust and £40,000 to the River Nene Regional Park Community Interest Company.
Kathryn Hardcastle, chief executive officer at River Nene Regional Park, said: “This contribution has allowed us to complete a £140,000 project at the Foot Meadow Island in the town centre which has improved the environment for people and for nature."
The brewery says they have also improved their draining system and paid the Environment Agency's response team's costs in full.
John Comont, conservation director for the Wildlife Trust for Northamptonshire, said: “We have ambitious goals to increase wetland diversity along the river Nene and around Northampton, not just on our treasured wildlife sites in the area, but equally in the connecting corridors and neighbouring areas that can help form a vital ‘network for nature."