Press release

Stream polluted by “negligent” Southern Water

2,000 fish die as double pump failure diverts sewage across fields into watercourse.

Almost 2,000 fish were killed in the incident.

Southern Water has been fined £330,000 after raw sewage escaped into a stream near Southampton for what the company admitted could have been nearly 20 hours.

Almost 2,000 fish were killed as faulty equipment at a pumping station sent untreated effluent into the environment at Waltham Chase on the edge of the South Downs.

Sitting at West Hampshire magistrates’ court, district judge Nicholas Wattam heard relay equipment at Little Bull pumping station had been wrongly programmed.

This led to a pump failing. When a second one wouldn’t start, sewage and other hazardous substances were diverted up through two manholes, across fields and into Shawford Lake Stream, leading to the popular YMCA Fairthorne Manor.

In the days after the incident in July 2019, investigators from the Environment Agency found pools of dirty water and polluted matter and vegetation in local fields. The stream was cloudy as pollution spread across nearly 3km. Ammonia levels in the water were 25 times the legal limit.

Scores of brown trout and other dead fish continued to be discovered. Tens became hundreds as the scale of the pollution emerged.    

Investigators believe the illegal flow of contaminated matter continued over public land and the stream for between five and 20 hours.    

Dawn Theaker, environment manager in Hampshire for the Environment Agency, said:

“We prosecuted Southern Water because of environmental harm caused by the pollution, a direct result of negligence in how the pumping station was managed.

“Yet again, we have a water company failing to properly respond to alarms when things go wrong at facilities they operate, allowing sewage to flow uncontrolled into fields and a stream. The court agreed with our case that Southern Water was negligent.

“Any pollution is unacceptable, but this one happened close to a Site of Special Scientific Interest and other designations meant to provide greater protection for nature.”

Water minister Robbie Moore MP, from the Department for Environment, Food and Rural Affairs, said: 

“Southern Water have rightly been punished today for damage to our natural environment and it’s just the latest example of how polluters are being held to account. Today’s fine will be paid into our Water Restoration Fund, which will support further work we are already doing to clean up our waterways.

“We are delivering the changes people want to see: more investment, stronger regulation and tougher enforcement on water companies. This includes our proposals to ban water company executive bonuses, and we recently gave the Environment Agency greater powers to impose uncapped civil penalties on polluters.”

The incident happened near where habitats and wetlands were previously given formal protection by conservation bodies, but it wasn’t just the ground and stream affected.

Southern Water paid compensation to the outdoor activity centre at Fairthorne Manor, downstream of the incident after a thousand bookings for water sports were cancelled. Concerns grew the pollution had spread. 

No water sports took place for ten days as the Environment Agency carried out its investigation.

The Environment Agency first heard something was wrong from a member of the public around noon on that summer’s day in 2019, saying he saw untreated sewage, solids and tissue entering the stream.

An alarm on the failed pump went off just after 7am, but Southern Water had failed to act on it. 

The Environment Agency sent an officer to the scene in response to the first report and fed back that the stream alongside the pumping station was cloudy, and there was a definite smell in the air.

The officer saw sewage debris had collected around one manhole in a field and then evidence of sewage coming out of another nearby.

He also saw the first of many dead fish as a result of the pollution.

The number of fish killed grew as the investigation went on. Brown trout, bullheads and sticklebacks all found lifeless in the water – 1,954 in all. Investigators saw no live fish in parts of the stream, only dead ones.

Southern Water pleaded guilty at an earlier hearing to one breach of the Environmental Permitting (England and Wales) Regulations 2016 regarding the pollution and operation of Little Bull pumping station on or around 21 July 2019.

In addition to the £330,000 fine, district judge Wattam ordered Southern Water to pay the Environment Agency’s costs of £18,764 and a victim surcharge of £181.

Southern Water was fined £90m in 2021 following widespread pollution of rivers and coastal waters off Kent, Surrey and Sussex.

Prosecutions of water companies by the Environment Agency for pollution incidents since 2015 have now led to fines of more than £150m.

For media enquiries only, please contact 0800 141 2743 or email Commmunications_se@environment-agency.gov.uk

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Published 27 February 2024