Multi-billion pound plans to 're-plumb' the north starts in Runcorn

The 25-year plan launched by United Utilities will see billions of pounds invested into projects across the north in a bid to deliver cleaner rivers, beaches and lakes.

By 2050 the goal is to ensure that storm overflows, the relief points that prevent sewers from backing up and flooding homes and businesses in heavy rain, each operate less than 10 times a year.

The Storm Overflow Reduction Plan, expected to cost some £19 billion in the north west region alone, will meet the new requirements of the Environment Act 2021, bringing a massive reduction in sewer pollution entering the region’s waterways. 

And work has already began in Halton with the Runcorn Wastewater Treatment Works project currently underway.

A whopping £4.1million is being invested into boosting the site’s storage capacity, reducing the frequency of storm water released into the Mersey.

In total in Merseyside, there will be improvements to 20 storm overflows representing an investment of £166m.

Jo Harrison, asset management director at United Utilities, said: “At United Utilities, our purpose is very clear – we don’t just supply water, we also want to make the north west greener, stronger and healthier.

“The multi-billion-pound programme we are now embarking upon will see the biggest overhaul of the region’s sewer network in a century.  Not only is this now enshrined in law, but it is also what our customers expect and it’s the right thing to do.”

There are more than 2,200 storm overflows within the wastewater system across the north west region.

Like the overflow on a bath, these are designed to prevent flooding and provide a route for water to take when sewers fill during heavy rain – automatically releasing a diluted mixture of sewage and rainwater into the environment.

Since December 2023, every one of these sites is now monitored, allowing United Utilities to build a picture of how often each site operates and which should be tackled first.

Improvement work will be prioritised at the sites which operate most frequently or which discharge into bathing waters or environmentally sensitive locations.

Jo Harrison added: “We are making a fundamental change to the way our sewer system has been designed and change on this scale cannot happen overnight.

“We are re-plumbing our drainage systems, building storage tanks to increase the capacity, separating rainwater out of sewers, and harnessing the power of nature to treat storm water before it is returned to the environment. Work has already started, and people are going to see much more of this over the next 25 years.”