Pennon, the British utility firm which owns South West Water, has blamed “exceptionally high” groundwater levels for an increase in sewage leaks and pollution incidents.
The Exeter-based firm said the third wettest October to August since records began had caused an “increase” in the headline number of storm overflows, despite wider concerns over the sector’s infrastructure.
Pennon argued the higher than normal rainfal and water tables in 2024 had also impacted the number of “pollution incidents, alongside the performance of a small number of treatment works.”
“We continue to invest in our infrastructure to make targeted operational interventions to protect the environment,” it said in a statement on the London Stock Exchange.
It comes ahead of a key determination by industry regulator Ofwat in December over th level household water bills will be set per year.
Lobby group Water UK has warned the current proposed cap, which limit any fee rise to 21 per cent, could create a “material risk” that utilities firms are unable to raise enough money to stop sewage leaks.
Pennon has faced significant backlash for the huge number of pollution incidents at South West Water last year, which nearly doubled when compared with 2023.
As sewage increasingly leaked into British rivers, chief executive Susan Davy raked in a bumper £860,000 pay packet, up from £534,000 the year prior.
Analysis from the Observer earlier this year revealed UK water firms leaked over one trillion litres of water last year.
“Supporting our customers remains one of our four priorities alongside tackling storm overflows, ensuring water resources and water quality, and driving environmental gains, with over 140,000 customers benefiting from our affordability initiatives with a 35 per cent increase in customers on our social tariffs,” Pennon said.
The group expects like-for-like revenue in its half-year results, released in late November, will be impacted by lower customer demand. Operating costs are expected to be broadly flat.