Isle of Wight leads way in effort to cut storm overflows
One year on from the landmark launch of our £1.5bn Clean Rivers and Seas Plan, our teams have already made great strides forward on the Isle of Wight by preventing 300 spills over the last two years.
Our work to reduce storm overflows on the Isle of Wight
The island has proven to be a perfect testing ground for the use of innovative engineering and nature-based solutions – designed to stop or slow rainfall entering our sewers, and when volumes are high, overloading our network of pipes, pumping stations and treatment sites.
It is this hydraulic overload which can result in the storm overflows being activated and flows being released into the environment, rather than causing homes and communities to be flooded.
On the Isle of Wight, our Clean Rivers and Seas Task Force have been busy assessing every area of our network and taking action, including upgrading pumping stations to increase their capacity, installing thousands of water butts in customers’ gardens to capture rainfall, and partnering with key organisations like Isle of Wight Council to work together on tackling the causes of storm overflows.
This follows on from the release of our £1.5bn Clean Rivers and Seas Plan last year.
Keith Herbert, Pathfinder Delivery Lead West for Southern Water said:
“We’re really pleased that our work on the Isle of Wight is really starting to bear fruit now, and that our range of interventions are making a real difference with 300 spills prevented over two years.
“Our teams have been working really hard, but it hasn’t been easy. We experienced the wettest 18 months on record since 1836 between October of 2022 and March of 2024, which resulted in flooding across the island in both years.
“We know we still have a long way to go but a year on from the launch of our Clean Rivers and Seas Plan, we are excited to be in the final stages of scaling up many of our solutions so we can prevent even more spills."
Ways we're reducing storm overflows on the Isle of Wight
Appley
Our work at Appley Wastewater Pumping Station has already helped to reduce storm overflows along the island’s coastline. We've worked closely with the Environment Agency so we could change the permit of the site.
This meant we could quadruple the sites storage and double its flow rate – this has helped prevent 88 spills between May and September this year.
Cowes
We optimised pipework underneath Terminus Road that caused water to back up into the sewer system triggering storm overflows. We replaced this pipework and installed AI technology (a smart sewer gate.
Since completion, there have been no storm overflow releases from the Terminus Road overflow, despite heavy and frequent rainfall. This has helped prevent 88 storm overflows since December last year.
Havenstreet
We found that surface water draining was a real issue here and our work in the area has helped slow the flow of water entering the sewers by offering residents water butts. We have extended the water butt scheme to Cowes, Gurnard, Fishbourne, Wotton, Yarmouth and Freshwater
Yarmouth
Our teams have installed a tidal ingress protection flap to relieve the pressure of high tides on the storm overflow outfall. This has kept equipment working properly and reduce emergency alarms and storm overflows at Norton Spit.
Binstead
We've offered free household sustainable drainage systems to reduce flood incidents and surface water. We've also worked with the Isle of Wight Council to improve the local flood strategy along with trialling a new repaving scheme.
New partnerships
Our new partnership with the Isle of Wight Council will transform roads across the island in an effort to cut storm overflows and flood risks.
Find out more about our interventions on the Isle of Wight on our Isle of Wight Pathfinder project page.