The regulator has been working with water companies since they were privatised in 1989 to tackle the impact of overflows that release sewage into watercourses and coastal waters in England and Wales.

£2.5bn has been spent on the programme over the last two decades, with 6,000 of the most polluting outlets being rebuilt, removed or upgraded to ensure a cleaner outflow.

The other 4,193 overflows in the two countries have been signed off as posing a low environmental risk.

Historically sewage overflows have been a necessary evil, allowing excess water and sewage to release into the sea or rivers during extreme weather such as heavy rain or flooding, preventing it from backing up into streets and homes.

Paul Leinster, chief executive at the Environment Agency said: “We want the cleanest possible rivers and seas. To achieve this, the amount of pollution going into them needs to reduce.

“We’ve been working with the water and sewerage companies to identify the highest sources of pollution from sewage overflows and together have acted to tackle them.

“By also bringing the lower risk overflows under stricter regulation, we’re ensuring the quality of rivers and coastal waters continues to be protected and improved.

“Water and sewerage companies now have a legal duty to monitor and maintain the overflows so that there are no serious pollution incidents. We will enforce this wherever necessary.

“Water utilities have a big responsibility in helping to maintain and improve inland and coastal waters. The programme of river and habitat protection the Environment Agency oversees will mean that rivers and coastal waters are protected for people, wildlife and the environment.”

Sam Bond

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