Two UV Liners Installed in London

OnSite has installed two iMPREG UV liners through a sewer underneath the railway in Kentish Town, London.

The sewer was so deteriorated that a permanent CCTV feed had been installed to allow for permanent monitoring in case conditions worsened, while excavation works had occured at the beginning of the project as the downstream and upstream manholes were inaccessible.

OnSite installed an iMPREG GL16 DN300 7.4 mm UV liner in the invert, with the liner then grouted and left to set.

An iMPREG GL16 DN600 12.8 mm UV liner was then installed on top of the set grout and the remaining annulus pumped with more grout, before the catch pits were reopened and the manhole was reinstated.

OnSite is one of the UK’s leading providers of specialist contracting services, while iMPREG liners are among the most frequently used sewer rehabilitation liners in the world.

For more information visit the OnSite website.

If you have news you would like featured in Trenchless International contact Managing Editor David Convery at

The above article was originally published in Trenchless International, the official publication of the ISTT. For further information visit

Privacy Preferences
When you visit our website, it may store information through your browser from specific services, usually in form of cookies. Here you can change your privacy preferences. Please note that blocking some types of cookies may impact your experience on our website and the services we offer.