South West Water drastically reduces storm overflow spills at England’s former highest spiller and delivers significant reductions in pollutions across the region

South West Water is continuing to drive improvements to its environmental performance which have seen pollution incidents halve in the eight months to August 2025, and storm overflow spills reduce by nearly 50% in the last year.

One of those storm overflow locations that has seen a reduction in use is at Salcombe Regis, which was home to England’s highest spilling overflow in 2024, operating every day of the year.  

South West Water’s efforts to tackle illegal connections to the local sewer network has made vast improvements, cutting the number to just one spill in the 70 days since work was completed in August.

South West West has acknowledged that there is more to do, and backed by its largest ever investment programme and spearheaded by the full force of its brilliant teams working hard every single day, it is working to keep reducing its impact on the environment and make the changes everyone wants to see.

This drive towards a better, cleaner future saw it become one of only a handful of companies to reduce the number of pollution incidents in 2024.

South West Water’s focus has been twofold. Firstly, reducing pollutions to homes, businesses and land. As a result, internal sewer flooding to homes and businesses has reduced by 68% in the past 5 years. External sewer floodings have also fallen by 24% since 2020. Across the South West, homes and businesses are now less likely to experience flooding than in any other part of the UK.

The company’s investments are making a difference right across the region, and it has many examples of multi-million-pound projects being delivered to upgrade its network, reduce pollution and tackle illegal connections.

Removing unauthorised connections in Salcombe Regis

One example of where this monitoring has proven to be vital is Salcombe Regis, where the storm overflow at the wastewater treatment works operated every day during 2024. Thanks to the data South West Water could see, it investgated the cause of the high spill numbers and discovered that several significant illegal connections to the sewer network were contributing high levels of additional flows into the sewer.

This includes highway road gullies with extensive road run off which were allowing water to enter sewers, dramatically increasing the levels in the network and causing the storm overflow to operate.

As a result, South West Water has been working hard to remove several illegal connections within the Salcombe Regis catchment. In the 70 days since 12 August when this work was completed, there has been one storm overflow spill, where previously it was operating daily.

Protecting the environment in Exmouth 

South West Water maintains and operates 14,332 miles of sewer over a vast and varied landscape combining both urban and rural areas. This means that things can, and will, go wrong. When that happens the company works hard to put them right as quickly as possible.

One area where it has seen issues appear on its network in recent years is in Exmouth and South West Water is doing everything it can to protect the environment as part of a £38 million investment in the area, and to help Exmouth Beach maintain its ‘excellent’ bathing water quality status, which it has held since 2016.

This includes upgrading its pumping stations and treatment works to significantly reduce the number of spills.

Reducing the use of storm overflows 

As well as reducing the number of pollutions, South West Water remains focused on reducing the use of storm overflows, and has seen a 20% reduction in bathing water spills over the last five years.

As a result of multi-million-pound investment, and a year ahead of the government’s target, 100% of its 1,342 storm overflows are now fitted with Event Duration Monitors which record data at least every 15 minutes, with some sites capturing updates every two minutes and others as often as every 10 seconds.

By seeing what’s happening in its network every few seconds, it can act faster, plan smarter, and invest where it matters most.

Turning the Tide in Dawlish

South West Water’s first scheme as part of its record investment for 2025-2030 is currently well underway in Dawlish, where it is carrying out essential work to futureproof the town’s wastewater network. This will allow the network to perform effectively as Dawlish’s population continues to grow, and help improve the local bathing waters.

Several solutions are being delivered for the town, including new storm tanks – each with 2.2 million litres of storage – separating sewage from surface rainwater, and fixing issues where groundwater is seeping into existing pipework and putting added strain on the network. These are all designed to reduce storm overflow use.

Protecting bathing waters in Falmouth

Another area where it is working on a major project to reduce the use of storm overflows and protect the quality of local bathing waters is Falmouth.

The scheme involves building a new underground storm water storage tank to capture excess flows during heavy rainfall, holding them safely until there is capacity in the sewer network for full treatment. This will help to reduce storm overflow spills and safeguard water quality at Gyllyngvase Beach.

The new storm tank is just the first stage of improvements planned for Falmouth. South West Water is also exploring nature-based solutions and surface water separation schemes in the area to reduce pressure on the network and tackle spills from other storm overflows in the town.

Susan Davy, CEO of Pennon, said, “We are investing to improve our network across the South West and we’re already seeing tangible benefits. Pollution incidents have halved in the eight months to August 2025. Storm overflow spills have reduced by nearly 50% year-on-year, benefitting from interventions and investment in our wastewater network, alongside lower rainfall year on year in the South West.

“From Salcombe Regis to Falmouth, we’re demonstrating our commitment to the region, accelerating investment in innovation, monitoring, and operational excellence to meet the government target of fewer than 10 spills per overflow, per year, a whole decade early.

“Over the next five years, our record investment plan will see long-term resilience and environmental protection delivered across the South West, in response to our customers’ priorities.”