Water firms illegally spilled sewage on dry days - data suggests

Three large h2o companies illegally discharged sewage hundreds of times past twelvemonth connected days erstwhile it was not raining, a BBC probe suggests.

The practice, known arsenic "dry spilling", is banned due to the fact that it tin pb to higher concentrations of sewage successful waterways.

Thames, Wessex and Southern Water look to person collectively released sewage successful adust spills for 3,500 hours successful 2022 - successful breach of their permits.

Water UK, the manufacture body, said the spills "should beryllium investigated".

Releasing sewage into rivers and seas is allowed successful the UK to forestall tube systems becoming overwhelmed - but it has to person been raining.

Without rainwater the sewage is apt to beryllium little diluted - starring to build-ups of algae which nutrient toxins "that tin beryllium fatal to pets and airs a wellness hazard to swimmers", says Dr Linda May, a h2o ecologist astatine the UK Centre for Ecology and Hydrology.

Discharging successful adust conditions is truthful amerciable nether biology law.

Collectively passim 2022, Thames, Southern and Wessex illegally started releasing sewage connected adust days 388 times - probe by the BBC's clime and information teams suggests - including during past summertime when these regions were successful drought.

There adjacent appears to person been spills by each 3 companies connected 19 July 2022, the hottest time connected record, erstwhile temperatures topped 40C successful immoderate places and galore radical tried to chill disconnected successful rivers.

All 9 English h2o companies were sent biology accusation requests for information connected erstwhile their spills started and stopped. Only Thames, Southern and Wessex provided details - which the BBC past cross-referenced with Met Office rainfall information to place adust spills.

Fewer spills are apt to person been recorded successful 2022 by Thames and disclosed to the BBC. That's due to the fact that the institution lone had 62% of its overflow points monitored - compared to Wessex with 91% and Southern with 98%.

The remaining six h2o companies successful England said they couldn't supply accusation due to the fact that they were already being investigated for imaginable amerciable spilling by manufacture regulator Ofwat and the Environment Agency (EA). If the companies shared information with the BBC, they said, past investigation could beryllium carried retired which could sway nationalist opinion.

Thames, Southern and Wessex service much than 22 cardinal people.

Across the Wessex Water portion - from the Dorset seashore to the Bristol country - BBC investigation identified 68 sites wherever sewage whitethorn person been discharged illegally past year. The spills that started connected adust days look to person lasted for much than 1,500 hours.

In 1 case, the BBC's investigation suggested that sewage was discharged into the River Chew successful northbound Somerset from a adjacent wastewater attraction works for astir 50 hours during adust periods.

Georgie Duckworth swims and rafts regularly successful the stream with her 2 young boys, similar different section residents, and describes the spills arsenic "outrageous".

"We are each alert not to spell swimming, not to get your heads nether successful the h2o erstwhile it is raining, but the thought that it is happening successful adust upwind too, it's alarming," she told the BBC.

Wessex Water said the spills into River Chew were caused by groundwater coming up into pipes and forcing it to spill. It said this dilutes the sewage and "the tempest overflow is not identified arsenic 1 of the factors affecting the ecological information of the river".

However, the EA - England's biology extortion assemblage - told the BBC that immoderate adust spills owed to groundwater are a breach of licence and illegal.

Wessex Water besides contested immoderate of the different spills highlighted by the BBC, citing doubts implicit the accuracy of its ain data.

Nicholas Ostrowski, an biology barrister and h2o manufacture expert, says determination are 3 reasons wherefore h2o companies whitethorn beryllium spilling during adust upwind - attraction issues; "hydraulic incapacity" successful the system, wherever determination is not capable abstraction for h2o to spell done the pipes; and the institution "deliberately sending effluent retired successful adust weather".

Any amerciable spills should beryllium investigated by the EA. Enforcement enactment tin beryllium taken, ranging from a informing to an unlimited fine.

The authorities has revealed that the EA recorded 115 cases of amerciable cognition successful 2022 for the 3 h2o companies - little than a 3rd of what the BBC investigation found.

One of the agency's officers - who works successful biology regularisation - told the BBC anonymously determination was a "firm link" betwixt the EA's nonaccomplishment to place and analyse adust spills, and fund cuts and unit losses.

The EA's biology extortion budget, funded by the government's Department for Environment, Food and Rural Affairs (Defra), was halved betwixt 2010-20.

The serviceman besides told america the bureau was progressively relying connected h2o companies to study their ain adust spill incidents due to the fact that of these cuts.

The EA's main executive, John Leyland, told the BBC: "The backing for the Environment Agency is simply a substance of nationalist record... and we've seen a dependable diminution successful immoderate of our funds and truthful we've had to change.

"We've been focusing connected integer monitoring, but earlier this twelvemonth we announced a programme of accrued investments successful existent radical connected your riverbank."

On the BBC's findings of adust spills, the EA was incapable to remark due to the fact that of its ongoing transgression probe into h2o companies. But Mr Leyland said: "We are committed to expanding our regulatory beingness to clasp the h2o companies to account."

Water Minister Rebecca Pow told the BBC she considers the magnitude of sewage discharged into the English waters "utterly unacceptable", and said the extortion fund had been accrued by 12% since past year.

One evident dry-spilling lawsuit by Southern Water picked up by BBC investigation besides came to the Environment Agency's attraction aft a ailment from a subordinate of the public.

In March 2022, Robert Bailey from the Clean Harbours Partnership noticed his section chalk stream, the River Lavant adjacent Chichester, had go "discoloured for galore miles and was starting to capable with a achromatic plume".

His concerns correlate with 2 adust spills the BBC has present identified astatine the site.

"Because of the sewage being discharged, it is simply a stream of effluent," helium told us.

The BBC has seen the probe study from the EA's consequent visits successful April and May - which confirms that Southern Water was discharging sewage erstwhile determination was nary rain, successful breach of its permit.

The EA issued Southern Water with a informing - but said further enactment could beryllium taken if determination were much spills.

There were 91 much hours of sewage discharges starting during adust upwind astatine the tract during the remainder of 2022 - BBC investigation suggests.

In total, the probe indicates that Southern Water illegally released sewage astatine 25 sites crossed its country past twelvemonth - from Hampshire to Kent - for a full of astir 800 hours.

John Penicud, caput of wastewater operations astatine Southern Water, told the BBC that "so-called 'dry spills' are a analyzable issue" and said discharges successful adust upwind tin beryllium caused by groundwater entering pipes.

He added that: "Lavant is successful a catchment that is peculiarly prone to groundwater infiltration." He besides said the institution planned to put much than £1.6m improving much than 4km (2.5 miles) of sewers successful the area.

Another predominant spiller appears to beryllium Thames Water's Longbridge Road overflow tract successful eastbound London, which releases sewage straight into Mayes Brook.

The stream is located successful the UK's archetypal "climate" parkland successful Dagenham - constructed astatine a outgo of £3.8m to supply a greenish haven for the section assemblage and wildlife.

But past year, the overflow spilled for astir 200 hours - leaving excrement-soaked bedewed wipes connected the riverbanks.

BBC probe estimates that astir a 4th of those hours were from adust spills.

"You've got this opposition of an improved parkland costing millions of pounds, getting polluted each 4 days connected mean by sewage and that's a scandal," says Theo Thomas, main enforcement astatine h2o foundation London Waterkeepers, who has been lobbying Thames Water and the section authorization to resoluteness the issue.

A Thames Water spokesperson said they had been successful interaction with Mr Thomas and apologised for the tempest overflows which occurred.

"We've been assessing however we tin amended our Longbridge tract and the surrounding web and volition proceed to enactment with the section communities connected our concern plans," they added.

The BBC investigation suggests that Thames Water - with customers from the Cotswolds to the Thames Estuary - dry-spilled for 1,253 hours successful 2022, astatine 49 overflow sites.

On these spills Thames Water said: "The Environment Agency's methodology for calculating adust time spills is inactive being determined and we volition proceed to enactment with our regulators arsenic they specify this. We respect each discharges of untreated sewage arsenic unacceptable, and we person planned concern successful our sewage attraction works."

The figures were the effect of a nine-month probe by the BBC Data and Climate and Science teams.

Water and sewerage companies are liable for outlets known arsenic combined sewer overflows (CSOs), which merchandise sewage from attraction works oregon the sewage web into the UK's waterways.

The bulk of CSOs grounds erstwhile they discharge.

Every twelvemonth the sewerage companies pass the Environment Agency (EA) successful England however often and for however agelong each outlet discharges.

But the EA lone publishes the yearly summary of full spill counts and hours.

So the BBC sent Environmental Information Regulation requests to England's 9 h2o companies to get the commencement and halt times of each discharge recorded astatine CSOs successful 2022.

The commencement and halt times for the 3 companies that provided information were adapted into the modular 12/24-hour counting blocks utilized by the EA to find idiosyncratic "spills".

These were past cross-referenced with the highest-quality 1km-gridded rainfall data - disposable from the Met Office - to place spills occurring successful periods of adust weather.

This rainfall information is presented successful gridded squares that screen the onshore country of the UK. Each grid compartment is 1km by 1km square.

The rainfall values are calculated from a web of automatic rainfall gauges and reflection stations.

The EA defines a adust time arsenic 1 wherever determination was little than 0.25mm of rainfall connected that time and the time before.

The BBC took a blimpish attack of 4 consecutive days without rainfall to let for catchment drain-down clip - erstwhile rainfall moves done the hydrological system.

The methodology was independently reviewed by 3 world experts moving successful this field.

Additional reporting by Libby Rogers, Rob England and Nassos Stylianou. Graphics by Jana Tauschinski and Kate Gaynor

Methodology enactment from Dr Gemma Coxon, University of Bristol; Dr Nick Voulvoulis, Imperial College London; Dr Barnaby Dobson, Imperial College London