Guide aims to demystify drain and sewer lining

Rail culvert with UV lining

A new technical guide aims to explain best practice in the use of no-dig sewer and drain lining. The guide, from drainage specialist Lanes Group, also explains the pros and cons of the main lining techniques available to construction and maintenance contractors.

Lanes Sewer Rehabilitation and Lining Manager Simon Bull said: “Pipe lining is a highly sustainable way to extend the life of defective sewers by up to 100 years.

“It is safer, faster, less disruptive and more cost-effective than the conventional alternative, which is to excavate a pipe and replace it. In some cases, it is the only way a pipe can reasonably be rehabilitated.

“However, there are still many asset owners who turn to traditional dig-ups first. This guide aims to show them that it makes sense now to consider lining as a first option for pipe rehabilitation.

“It also shares our expertise in showing the benefits of different lining technologies, to help asset owners make informed judgements about how their pipes can best be rehabilitated.

“Our whole team has helped put this guide together, providing answers to the most frequent questions we get about lining sewers and drains, so anyone needing this type of service [can] get an accurate perspective on what can be achieved.”

Lining technology has advanced significantly in the last decade, with new techniques available to support specialist lining projects, including chemical effluent systems, large diameter pipes and complex pipe systems.

This includes the development of associated technologies, including robotic milling systems for preparing pipes for lining and opening lateral connections once liners are installed.

The guide explains the principles behind cured in place pipe (CIPP) installation, and the three main techniques available – ultraviolet (UV) light CIPP, hot water CIPP, and ambient CIPP.

All three techniques involve the insertion of a liner – made from felt or flexible glass reinforced plastic. A resin, or chemical catalyst, impregnated in the liner is then cured to create a tough, waterproof pipe-within-a-pipe. Lanes says it has been among the first firms to use lining to strengthen highway drains as part of smart motorway modernisation programmes, and to use UV lining to rehabilitate industrial pipes that need chemical resistance.