POLLUTION caused by a spillage from an overturned tanker carrying fertlizer has killed hundreds of fish in the River Witham just south of Grantham.
The tanker spilled 3,000 litres of diluted ammonia into the water system when it overturned in Church Street, North Witham, last Tuesday.
The chemical made its way into the River Witham where it has killed various species of fish in a 12-mile stretch between Colsterworth and Little Ponton, along with the protected white-clawed crayfish.
The Grantham Angling Association fly fishing section controls part of the affected river. Its chairman, Dean Kightley, said the protected species has been wiped out in the area, which was one of only a handful across the country where the crayfish could be found.
He said: “The upper Witham was one of the last places to find white-clawed crayfish. It really, really is such a shame.”
Volunteers from the association have spent hundreds of hours in recent years carrying out natural habitat improvements to attract wildlife and care for the welfare of the fish. Species that were found there included brown trout and perch - no live fish have been spotted since the contamination, said Mr Kightley.
One member of the angling association, Adrian Trumper, called the contamination a “tragedy in our own backyard”.
He added: “The beautiful haven for wildlife that is the River Witham valley between Grantham and Colsterworth was the haunt of kingfishers, water voles, wild brown trout, and the rare white-clawed crayfish. That is until last week.
“The river is now dead for nearly 12 miles, the fish have died a horrible death by suffocation.”
The Environment Agency was immediately called out to the incident in North Witham last Tuesday to minimise the impact on the environment.
Spokesman Rita Penman said: “By the time we arrived some diluted ammonia fertiliser had already escaped into the River Witham. Once this happens our role is then to minimise the impact on water users so we informed abstractors and land owners with cattle which drink from the river.”
Regular water samples have been taken from the river between Little Ponton and South Witham. Officers are no longer taking samples as the ammonia levels have been found to be greatly reduced.
Several dead fish have been spotted in the river along the stretch in Wyndham Park, Grantham. According to Ms Penman, these fish have been washed downstream, and are not thought to have died in the river at Grantham.