Dave Harvey,West of England business and environment correspondent and

Tess de la Mare,Bristol

BBC A close up of a piece of toilet paper caught on branches on the banks of the River Avon following Storm Henk in January 2024. BBC

Wessex Water said the deal means the money will be used to benefit customers rather than going to HM Treasury

A water company has agreed to fund £11m worth of improvements to cut sewage spills across its network to avoid a fine by the regulator.

Wessex Water and its shareholders will pay for upgrades to reduce spills at storm overflow sites, extra monitoring equipment, and to help customers better manage rainwater at their properties.

The company proposed the package to avoid a £10m penalty after an Ofwat investigation found it had failed to adequately maintain and upgrade its waste water network.

Wessex Water and Ofwat said the deal would mean the money would be used for the benefit of its customers and the local environment, rather than going to HM Treasury.

None of the sum will be paid by customers or added to bills, Ofwat said.

A public consultation will now be held on the agreement before Ofwat makes its final decision to give it the go-ahead.

Lynn Parker, senior director for enforcement at Ofwat, said Wessex Water’s lack of investment “meant there were spills from storm overflows when there shouldn’t have been”.

She added: “To their credit, the company has been one of the more proactive in investigating and rectifying the problems identified.

“However, there remain breaches which must be accounted for and corrected.”

Johnny Palmer stands on the bank of the River Avon after a swim. His top half is visible and he is only has a towel around his shoulders.

Clean water campaigner Johnny Palmer says the deal is “a drop in the ocean” of what is needed

Clean water campaigner and wild swimmer Johnny Palmer was sceptical the deal would have much impact, describing it as “a drop in the ocean”.

“It’s not an investment, they are just being told to do the things that we pay them to do so I challenge the concept of investment entirely,” he said.

A spokesperson for Wessex Water said: “We regret the impact our waste water performance has had on customers and the environment.

“When the issues at our treatment sites were identified we were quick to fix them, but we do agree that there is much more to do – particularly in areas where groundwater enters the sewerage network and can result in overflows operating long after rainfall events.”

“The proposals in this package will tackle the problem directly, sealing pipes on private land that we would not normally have powers over, as well as additional monitoring and initiatives like water butts and rain gardens to help customers treat rainwater as a valuable resource,” they added.

“This not only prevents pollution but also reduces the risk of sewer flooding for communities.”

The company said it was planning investment of £300m in its sewerage infrastructure by 2030, including expansion of key waste water treatment sites.

It added that a key part of its strategy is to encourage sustainable rainwater management to prevent it overwhelming the sewage system during heavy rain.

Water Minister Emma Hardy said: “Water company failures like these are unacceptable – polluting the environment and impacting local communities, and it is only right that Wessex Water has accepted it needs to make amends.

“We are taking urgent action to clean up our rivers, lakes and seas, including stopping unfair bonuses and introducing prison sentences of up to two years for polluting water bosses.”

Ofwat is conducting a country-wide investigation into failings by water companies, which has so far seen five providers pay £240m in redress packages.