Southern Water has been ordered to appear in court after being accused of polluting one of the country's most famous fishing spots.

A group campaigning on behalf of anglers has won a legal battle to make the company defend itself over claims it is responsible for diesel contaminating the River Test.

The River Test is one of only 200 chalk streams in the world, is a site of Special Scientific Interest and famed for its salmon and trout fishing and diverse wildlife.

The highly unusual case - the first private criminal prosecution of its kind for 20 years - has been brought by Fish Legal following 'persistent' discharge, including diesel, which has been blamed for the death of fish and cygnets.

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At a court hearing the group - a not-for-profit organisation of lawyers who represent anglers in their fight against polluters - faced opposition from both Southern Water and the Environment Agency (EA).

The EA already has an official investigation ongoing and wanted the Fish Legal case to be adjourned until after that had been concluded, a position backed by the water company.

But after hearing arguments from all three at Southampton Magistrates' Court, the judge ruled it would be 'fundamentally' wrong to deny the prosecution.

Joe Hart, on behalf of Fish Legal, said: "It has been with a degree of frustration that Fish Legal bring this prosecution to a river where there is an urgent issue.

"The fact the Environment Agency is investigating is not a problem."

Criticising the EA's length of investigations, he added: "The average time taken from commencement of an investigation to first appearance in court, last year, was 557 days.

"And there are similar average times taken in preceding years.

"This is an urgent matter that is having a significant environmental effect on a rather special river."

Daily Echo: Anglers and Fish Legal campaigners have taken Southern Water to courtAnglers and Fish Legal campaigners have taken Southern Water to court (Image: Solent News and Photo Agency)

District Judge Peter Greenfield said he said he could see 'no reason' why a summons couldn't be granted on Fish Legal's behalf.

"I think they are interesting arguments, but there is a fundamental right to issue a summons," the judge added.

He declared an initial summons, granting Fish Legal's application. The case is scheduled to be heard early next year.

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Before the hearing, Fish Legal said they had been 'forced to take a private prosecution' because pollution keeps entering the 'precious' chalk stream from an 'outfall' operated by Southern Water.

The section between Romsey and the estuary, the focus of the criminal case, is currently classed as 'unfavourable' due to polluting discharges.

Chair of Fish Legal, George Graham, said: “After years without effective action by the Environment Agency, we have been forced to take a private prosecution to protect this precious chalk stream.

"Both the water company and regulator are fully aware of the persistent pollution coming from this outfall.

"We cannot stand by any longer and wait for them to act.

“Ordinarily we use the civil law to take legal action against polluters on behalf of our angler members. However, in this case, we have taken the unusual step of going through the criminal courts.”

Head of practice, Penelope Gane, added: “Southern Water is bottom of the league for total pollution incidents in recently published Environment Agency environmental performance reports.

"In bringing this case, our aim is to stop Southern Water from polluting the River Test. It is that simple.”

The water company has been under fire for years for failures in its water supply, filtration system and raw sewage spills across the South.

Last Christmas, tens of thousands of householders faced the prospect of spending the holidays without running water because of burst pipes during the cold temperatures.

Hundreds of motorists were forced to queue to collect bottled water only a few days before Christmas Day.

Two months later, Southern Water shut off the water supply for 10,000 properties because 'untreated water was not being filtered correctly.'

The legal action follows diesel pollution over the last two years which Southern Water claims its teams 'quickly' dealt with, working with other organisations to protect the river.

A spokesperson for Southern Water said: “In June 2021, we were made aware of a release of diesel in the area of the Nursling Industrial Estate that escaped into the Little River Test.

"Our teams worked quickly, and with other agencies, to protect the watercourse and surrounding environment.

"An Environment Agency investigation into the cause of the incident and the identity of the polluters is ongoing.”