Making wild swimming a reality in Britain's rivers

In July 2020, Ofwat, the water industry regulator, with the support of the British government, laid down a challenge to water companies. They wanted them to find new ways to help the country’s economic recovery and pitch for green project funding worth £2.7bn. 

Across England and Wales, this new funding is now being put to work to reduce harm caused by storm overflows and trialling the creation of two new bathing rivers; collaborating with local partners to reduce the risk of flooding, protect habitats, and cut pollution; and developing innovative improvements in drinking water treatment and supply.  

Severn Trent Water was awarded the greatest share of the funding to invest in a number of projects including a £78m initiative to improve water quality at the River Avon and River Teme in the West Midlands, with the aim of making them clean enough to swim in. In January 2022, the UK's Environmental Audit Committee said the government should actively encourage the designation of at least one widely used stretch of river for bathing within each water company area by 2025 at the latest to improve water quality. To date, the UK only has one river in the UK – the River Wharfe in Yorkshire – that has an area designated as bathing water. 

Based on RPS' significant experience and track record of urban drainage planning, as well as its understanding of combined sewer overflow (CSO) behaviour and monitoring, Severn Trent appointed RPS to model five of the six catchments. By reducing harm from CSO’s through a reduction in spills, the stretches of rivers have the potential to be designated as inland bathing waters. The project also involves working with third-party partners and highway authorities.

To gain a better understanding of network performance, RPS has undertaken detailed hydraulic modelling, flow surveys and asset surveys and tested how potential solutions would operate and perform in reality.

One of our challenges is how to innovatively build back greener, rather than simply build more storage tanks for retention. Examples of greener solutions that we are exploring is surface water separation and the use of sustainable drainage solutions. This involves working out where it’s possible and economic to connect the flows from roofs and highways into the river network rather than taking the flows to the sewage treatment works via a combined sewerage network.