One of the UK's biggest water companies has been fined �200,000 for polluting a river after an Essex fisherman took out a private prosecution.

Basildon Crown Court also ordered Anglian Water to pay Roy Hart �9,500 to cover his legal costs in bringing the action over the pollution of the River Crouch with raw sewage.

The Environment Agency said that it had been planning to bring the action itself, but had been waiting for its investigators to gather complete evidence.

Mr Hart, aged 53, said afterwards that he had brought the case himself because he was annoyed by the agency's attitude.

'Mechanical failure'

He took the action when he spotted the sewage while fishing in the river near his home in Battlesbridge in October.

At a hearing before Basildon magistrates last month, he said it was the worst case of pollution he had seen on the river in 25 years.

The company, which admitted the charge, said the sewage discharge had been caused by an "unfortunate and unforeseeable mechanical failure" at a nearby treatment plant.

It is estimated that about 200 tons of sewage had seeped out over four-hours, leaving the river brown and killing hundreds of fish.

Law book

Speaking after the case, Mr Hart said that he had taken out the prosecution because he was annoyed by the attitude of the Environment Agency.

He told BBC Radio Five Live: "I got the Readers' Digest book of law and went from there."

A spokesman for the Environment Agency said it had tried to persuade 53-year-old Mr Hart to let it take over the action, and had provided evidence to support the case.

"The outcome is obviously a good result for Mr Hart and we are pleased with the fine.

"However, we believe we could have mounted a stronger case and we would urge people to leave prosecutions to us in these situations."

A spokesman for Anglian Water said: "We are committed to the environment and to its improvement.

"Three billion pounds has been spent over the last 10 years on environmental improvements, resulting in nearly 50% improvement in water quality in the region."

The fine is thought to be one of the largest ever imposed against a water company for river pollution.