Ben Maguire renews jail call after South West Water rated ‘poor’

Four regulators put their names to a single report for the first time today, and when it came to South West Water’s environmental record they needed one word. Poor.

North Cornwall’s Liberal Democrat MP, Ben Maguire, says the findings show the company is “still completely failing on sewage pollution”, and he is renewing his call for prison sentences for water bosses who repeatedly break the rules.

What the regulators found

The Water Industry Performance Insights report was published on Thursday (29 October) by the Environment Agency, Ofwat, the Drinking Water Inspectorate and Natural Resources Wales. It is the first time the four bodies have brought drinking water quality, environmental performance and customer service together in one overview for England and Wales. It covers the 2025 calendar year and the financial year to March 2026.

For South West Water, which serves more than 2.3 million people, the report records 137 pollution incidents, three of them classed as serious. Of its sewage incidents, 71% were reported by the company itself. Ben’s office says that ranks among the worst self-reporting rates in the industry.

Sewer flooding inside homes and other buildings rose by 74% on the previous year, although the report notes the company’s rate is still better than the industry average. The average time properties went without a water supply rose almost fivefold, and the regulators named the company as one of the worst performers in the industry on supply interruptions.

On customer satisfaction, South West Water ranked 15th out of 17 companies, the same position as the year before. The regulators said the company “must substantially improve customer interactions and overall experience”.

Where the company scored better

Drinking water quality was rated “exceptional”, with 99.96% of tests compliant. The company completed 94.2% of its required environmental improvement actions on time. Four of its 69 planned actions were not delivered, and the industry-wide figure was 93.7%. Leakage per property, at 102.2 litres a day, was below the industry average, though total leakage rose by 5.4%.

Because of potential water treatment risks, the Drinking Water Inspectorate is requiring South West Water to complete a transformation programme.

Ben Maguire’s call for tougher penalties

Since his election, Ben has campaigned for much tougher consequences over what he describes as South West Water’s “flagrant” sewage dumping. He wants prison sentences for executives responsible for repeated illegal sewage dumping, and he wants fines on water companies put back into local water projects and customers’ pockets. He has also pressed the company to bring forward upgrades and invest in storm overflows far sooner than its stated timelines.

“This report today confirms what my North Cornwall constituents already know: South West Water is completely failing them on sewage, service delivery, and other core areas of performance,” he said. “The regulators call its environmental performance ‘poor’, and say it must ‘substantially improve’ its customer service. Both of these might just be contenders for understatements of the decade.

“Sewage flooding into homes in the region is up 74% year-on-year under South West Water’s watch, while supply interruptions have gotten almost five times worse, and the company is still failing to self-report a significant proportion of its sewage pollution incidents. It’s of course particularly surprising they are not reporting their own sewage dumps.”

What happens next

The regulators say they will keep using their existing powers, including financial penalties, enforcement action and requirements for improvement plans. “We will support companies that are improving, and challenge those that are not,” the report says.

Ben doesn’t think that goes far enough.

“Regulators say they will take action, but my constituents know that any fines against South West Water are treated just as the ‘cost of doing business’,” he said. “I want to see proper penalties for water bosses who repeat offend, including prison sentences, with vital upgrades to storm overflows brought much further forward than planned. I’ve also been calling for any fines issued to actually benefit the communities, and the billpayers, who are affected. The Government must act now.”