Southern Water has been fined £3,000 after it admitted polluting 2km of a Sussex stream with raw sewage, killing up to a hundred brown trout and devastating the fish population for the second time in five years.Crawley Magistrates’ Court heard last week that the Environment Agency received calls from members of the public after dead fish were seen in the Sunnyside Stream in East Grinstead on 30 August last year.Environment officers who went to the site found nearly 100 dead brown trout along 2km of the stream. Water sampling take at the site found that dissolved oxygen in the stream was as low as 25 per cent along the stretch and there were traces of ammonia in the water.Officers traced the source of the pollution to a sewer pipe in nearby Brooklands Park. Subsidence below the pipe led to it buckling and eventually breaking, which led to the sewage getting into the stream.
The court heard that a similar incident in September 2005 occurred along the same sewer line running through Brooklands Park. That killed nearly 500 fish in the same stream, and it is probable that the fish population was still recovering, which led to less deaths on this occasion.
Slow leak undetected by Hawkeye telemetry
The company knew that the sewer was in an environmentally sensitive location, and a Hawkeye remote telemetry system was installed in 2008. This triggers alarms if flows exceed or fall below certain thresholds. However, in this instance, because the leak was a slow one the system did not pick it up.
Environment Agency Area Manager James Humphrys said:
“The Environment Agency tries to take a constructive approach to regulation and avoid unnecessary prosecutions. This was clearly a serious incident which affected the health of the stream and led to the deaths of around 100 brown trout. The stream is also home to brook lamprey, which are a protected species.
“This is the second time the stream has been spoiled by sewage pollution, and we are pleased the court has given Southern Water a hefty financial reminder to all water companies and other businesses that they must take their environmental responsibilities seriously. “
Southern Water pleaded guilty to one charge of polluting a water course in breach of Water Resources Act. The court fined the company £3,000 and ordered it to pay £4,833 costs and £15 victim surcharge.
With the UK government demanding a 50% reduction in storm overflow spills by 2029, the era of reactive management is over. Speaking in the House of Commons on 21 July 2025, then environment secretary Steve Reed said, “This Government will cut water companies’ sewage pollution in half by the end of the decade.”
ERG, the leading supplier of odour control systems and industrial gas cleaning & thermal systems, has been awarded the coveted King’s Award for Enterprise.
Welsh Water’s new artificial intelligence-driven tool, ORAI, has been shortlisted for three categories at the prestigious British Data Awards 2026 – underscoring the company’s commitment to using cutting-edge technology to deliver better outcome for customers.
Barhale has completed work on two separate Rapid Action Taskforce Spills projects it is carrying out for Severn Trent.
Hear how Scottish Water has completed its £235 million Ayrshire Glasgow Resilience Project - customers across Greater Glasgow, Ayrshire and East Renfrewshire will now benefit from a more secure and resilient water supply.
Hear how United Utilities is accelerating its investment to reduce spills from storm overflows across the Northwest.
Find out more about the remarkable career opportunities on offer at WSP - scroll down to watch the inspirational video.