United Utilities chemical leak killed fish in Bolton river
Water company United Utilities has paid more than £600,000 after a chemical leak polluted a river and killed fish.
The Environment Agency (EA) said an "acidic ferric salt solution" from a water treatment plant had seeped into the River Douglas in Bolton.
United Utilities offered to pay £500,000 towards improving river habitats and £88,498 to make sure there would be no repeat of the breach.
The company said it apologised for the incident.
"At the time, we fully cooperated with the Environment Agency's investigation, and took the necessary action to prevent a reoccurrence," a spokesman said.
Reports at the time of the chemical leak in 2016 said hundreds of fish - including brown trout - were killed, with many seen floating at the surface of the river.
United Utilities admitted fault and made the offer to pay as part of an Enforcement Undertaking, a civil sanction that can be used by the EA to punish environmental offences.
Polluters can make an offer to the agency to pay for improvements as an alternative to any other legal action.
An investigation began after fish were found dead close to where the river flows out of the Rivington Reservoir.
The water had turned a brown colour and became too acidic for fish - including brown trout - to survive.
Tests showed it had been contaminated by chemicals which were traced to United Utilities' water treatment works.
A faulty valve had been allowing the solution to enter the river by a drain.
Jennifer Hall, of the EA's land and water team, said: "We take tough action against any company or individual who causes significant pollution and damage to the environment."
United Utilities also paid £13,521 to cover the EA's costs.