A brand new wetlands scheme in a West Sussex area will help Southern Water in its efforts to reduce storm overflows into Chichester Harbour and improve water quality.

An image of the new wetlands at Lavant Wastewater Treatment Works

A brand new wetlands scheme in a West Sussex area will help Southern Water in its efforts to reduce storm overflows into Chichester Harbour and improve water quality.

The project, involving the planting of more than 1,500 reed plants, will be completed in the next few weeks on Lavant Wastewater Treatment Works.

Creation of wetlands sites is one of a number of nature-based solutions being rolled out by Southern Water to tackle storm overflows, as part of a major multi-million pound 2-year programme announced on Monday.

Lavant and the Chichester area is particularly impacted by high levels of groundwater overloading the sewer both the private and public systems. The increased pressure results in storm overflows, where releases are made into the environment instead of flooding homes and communities.

Wetlands provide a natural solution by remove contaminants from wastewater, like nitrates and phosphates, and can also improve local biodiversity, as well as having the green benefits of absorbing and storing carbon.

The new investment in this area will also involve sealing private and public sewers helping to prevent pressurised groundwater infiltrating the system.

Nick Mills, head of Southern Water’s Clean Rivers and Seas Task Force, said:

“We’re looking at lots of different solutions to tackle the use of storm overflows, wetlands will be an important part of our plans moving forward.

“They’re a fantastic natural and sustainable solution that can treat stormwater and improve our local environment.

“We look forward to creating many wetlands across our region over the coming years.”

On Monday Ofwat announced proposals which, following a short consultation, would allow Southern Water to further accelerate its vital work in driving down the use of storm overflows, enabling an ambitious two-year programme to expand its nature-based and engineering solutions.

Following a number of successful pilot schemes, the water company has proposed the roll out of a range of innovative projects to Ofwat to stop and slow surface and groundwater reaching the sewer system, across three areas within its region:

• Isle of Wight
• Kent’s North and East coasts
• The Harbours and South Downs areas of West Sussex and Hampshire.

The proposals would see an investment of up to a further £50 million between now and spring 2025.

As well as improving the existing network, and ensuring all sewer pipes are connected correctly, much of this funding will be spent on ‘greening’ communities, including:

• installing raingarden planters
• introducing swales and tree-pits to urban areas
• embarking upon new wetland schemes in the countryside

Lawrence Gosden, Southern Water CEO, said:

“Reducing the use of storm overflows and their impact on water quality is a priority for me. To do this we have to get to the root of the problem and reduce the amount of surface water entering the sewerage system.

“The opportunity to accelerate our rollout of the innovative and sustainable drainage solutions we have already piloted, on a much larger scale in three specific areas, is a positive opportunity. These tactics have proven to help reduce volumes of surface water, stop sewage spills, and bring nature back to communities.

“This comes ahead of a much wider investment of billions of pounds over the coming decades, marking the beginning of the end for storm overflows.”

Work on the Isle of Wight will build on activity already taking place in Gurnard and Cowes, before moving onto Fishbourne, Wotton, Yarmouth and Freshwater. I

The focus in the Harbours and South Downs area is on tackling storm overflows driven by pressurised groundwater inundating both private and public sewers. The programme will involve sealing off sewers, including private stretches and the rollout of wetlands in at least four sites by 2025. Benefits will also include biodiversity net gain and carbon reduction.