In a new project to protect communities in the village of Funtington in West Sussex, Southern Water teams are starting working to seal sewers.

The water company is continuing its major programme of works to protect homes from flooding and protect its network from the impacts of groundwater entering sewers.

Funtington, west of Chichester, will take centre stage for works to seal sewers to help keep out groundwater, which will also help reduce storm overflows in the area helping protect Chichester Harbour.

The work at Funtington forms part of the Bosham storm overflow reduction project, that was launched earlier this year to drive down storm overflow releases in this area.

Southern Water is now also close to completing work to seal sewers in East Dean, with more than a kilometre worth of sewers being sealed since July.

Both East Dean and Funtington are impacted by groundwater levels. Over the last two years, the issue has become even more acute as the impacts of the wettest 18 months since records began has led to more groundwater getting into sewers. The utility said that while groundwater is essential for feeding natural water sources like chalk streams, it can cause issues when it enters the sewer network.

It is hoped that through extensive sealing of sewers that the area will be better prepared during periods of rising groundwaters, meaning there could be less reliance on tankers and other measures.

Southern Water says that if the pipes are sealed, and less groundwater is getting in it means its treatment works are under less pressure. This could help reduce storm overflows and help the health of nearby watercourses that feed into Chichester Harbour.

The technique has been trialled elsewhere and proven successful, for instance in the pan parishes area of Hampshire near Andover, sealing private and public pipes reduced the number of tankers being used by more than 85 per cent.

The water company explains that its sewers are built to handle wastewater, so excess groundwater can overwhelm the system, reducing capacity and putting the network under pressure. In the worst-case scenario, tankers are used to remove excess water from the sewers to be treated at Southern Water sites - with approval from the Environment Agency, the company can also pump water from the sewers into the environment. However, Southern Water acknowledges that while this helps relieve pressure on the network and reduces the risk of foul sewer flooding, it is only a temporary solution.

Joff Edevane of Southern Water’s Clean Rivers and Seas Task Force said:

“We’re delighted to start work on sealing sewers in Funtington, our programme of work in West Sussex is continuing at pace and we know that it will make a real difference in tackling the issues caused by groundwater.

“By doing this work we can help protect our network and customer’s homes for when heavy rainfall and groundwater issues arise over the coming months.”