Southern Water is using innovative techniques and investing £20 million to renovate 12 kilometres of Victorian sewers across Ramsgate.

The unique sewers were built over a century ago by miners who dug underground tunnels through the chalk, up to 10 metres deep in some places. The tunnels remain in place and continue to act as a conduit for the sewer network.

The sewers are now in need of attention to ensure they can continue to carry flows safely from properties in Ramsgate to Weatherlees treatment works.

Specialist technicians, who are trained to work in deep tunnels using breathing apparatus, have been working to seal and line sections of the tunnels, repair existing sewers and build new pipelines.

The team, from contractor Clancy Docwra, is also building new - and enlarging existing - manholes to make access easier and safer.

Southern Water’s Senior Project Manager Adnan Naeeni said:

“From an engineering perspective, this is a complex but exciting scheme. The Victorians created a unique sewer network in Ramsgate, by building tunnels to house the pipes, rather than trenches. This has given us some unusual challenges, not least how we access the sewers to start the work - which is where our specialists come in. They are working deep underground, refurbishing the sewers and building new ones where necessary. The end result will be a more robust sewer network for Ramsgate, which will have many benefits."

The £20 million project, which started in July 2014, is part of a wider scheme to renovate sewers across Thanet, which represents an investment of more than £80 million over 10 years.

The team in Ramsgate is:

• Lining 5.5 kilometres of existing tunnels
• Rehabilitating more than 12 kilometres of sewers
• Building more than two kilometres of new pipeline
• Improving 98 manhole shafts
• Building 15 new manholes.