Boosting flood protection in Chippenham

We're investing £2 million towards reducing the flooding risk to homes in the Wiltshire town and protecting the River Avon.

What are we doing?

A six-month scheme will see extra capacity added to the sewer network, which will also be upgraded in the east of Chippenham to prevent the system from being overwhelmed and potentially spilling over on to nearby properties.

A 10-metre deep storage tank, sunk below ground on land off Long Close, will also play a vital role towards reducing times when high volumes of rainwater cause storm overflows to operate automatically to relieve pressure on the system.

Why is it needed?

Wessex Water project manager Paul Delves explained: “By building this additional storage, we can help to ensure the sewer network’s ability to withstand the arrival of large volumes of water in a short space of time, such as during a heavy storm.

“The tank we are building will be able to hold an additional 250,000 litres of water back from the network, to ensure the threat of the system becoming overwhelmed and causing flooding to nearby homes is diminished.

“This stormwater combines in the sewer with the foul water from homes and businesses and can also cause overflows to operate, but by retaining it in the tank, it can be returned to the sewer later, prior to being piped to a water recycling centre for treatment. “We’re also building more than 200 metres of gravity sewer and nearly 300 metres of rising main as part of our investment in the area.’’

Working with the community

The project gets under way in July 2024 and is expected to be completed by the end of January next year, with work taking place on some of the roads in the area between July and September.

Sewer construction means London Road will be closed to through traffic from near Wiltshire Tyres to near Pack Horse Inn between 25 July and 31 August, with Black Cross closed between the junctions with Long Close and London Road for installation of the gravity main between 26 August and 20 September.

A further closure will be on a short section of Long Close near the junction with Black Cross between 16-27 September.

A play area next to the site of the new storage tank will remain open while the project is in progress.

Project manager Paul Delves added: “We’ve worked closely with Wiltshire Council to minimise the impact of these road closures and have written to customers in the area about this work.

What else are we doing?

Wessex Water is proposing its largest ever investment in water and sewerage services to improve the health of rivers, reduce pollution and create around 2,000 extra jobs across the region, as part of a £3.5 billion package between 2025 and 2030.

The Business Plan, which includes £400 million of investment towards reducing discharges from storm overflows through a programme of work that will include nature-boosting wetland creation, is currently being scrutinised for final decision by industry regulators.