Three major water companies allegedly broke the law by discharging sewage water on days of no rainfall in 2022, according to a report.
The companies – Thames Water, Wessex Water and Southern Water – are accused of engaging in “dry spilling”, a prohibited practice of discharging sewage into rivers and seas during dry weather, following an investigation by BBC News.
Pumping raw sewage into the environment is permitted only when firms are dealing with “unusually heavy rainfall”. But the investigation published on Tuesday says these three water companies collectively released sewage in dry spills for approximately 3,500 hours throughout 2022, in violation of their permits.
Dry spilling is banned because it can lead to higher concentrations of sewage in waterways, posing environmental and health risks.
Without rainwater, the sewage remains undiluted, leading to issues such as the growth of algae, which can produce toxins “that can be fatal to pets and pose a health risk to swimmers”, Dr Linda May, a water ecologist at the UK Centre for Ecology and Hydrology, told the broadcaster.
The companies allegedly initiated dry spills 388 times in 2022, even during periods of drought and on the hottest day on record, 19 July 2022, when temperatures exceeded 40C in some regions.
Water UK, the industry body, has called for an investigation into these allegations.
Last year, an analysis by campaign group Surfers Against Sewage (SAS) found that the law prohibiting dry spilling had been ignored by several water companies with 146 dry spills detected from October 2021 to September 2022.
The research published in 2022 found Southern Water responsible for four times as many dry spills as the next worst offender, South West Water.
The new BBC report alleges that instances of these illegal operations are three times higher than the Environment Agency’s records. An anonymous EA worker told the BBC that there was a “firm link” between the agency’s failure to identify and investigate dry spills and budget cuts and staff losses.
The officer told BBC the agency was “increasingly relying on water companies to report their own dry spill incidents because of these cuts,” the report said.
“We are committed to increasing our regulatory presence to hold the water companies to account,” the Environment Agency was quoted as saying.
Southern Water’s head of wastewater operations, John Penicud, told The Independent that “so called ‘dry spills’ are a complex issue” and the company was required to report incidents as “spills” even when they were caused by rising groundwater entering pipes.
“We work with the Environment Agency and stakeholders to cut these so-called ‘dry spills’ – and all forms of water and wastewater releases,” he said.
A Thames Water spokesperson said: “There are a number of methodologies for defining and calculating why and how dry day spills occur. The Environment Agency’s methodology for calculating dry day spills is still being determined and we will continue to work with our regulators as they define this.
“We regard all discharges of untreated sewage as unacceptable, and we have planned investment in our sewage treatment works... Stopping discharges altogether will take time and sustained investment, however each step we take on this journey is a move in the right direction.”
A spokesperson for Wessex Water noted that the new report only focuses on three major companies “because other water companies refused to provide information”.
The company said three spills identified by the BBC were due to rising groundwater – and therefore legal. It described such incidents as “a known issue that is being fixed as part of the industry’s £10bn investment programme”. It contested the claims on other spills, although the BBC said these were based on its own data.