Expertise 03 / Trenchless
Trenchless rehabilitation
Renovating existing networks from the inside: CIPP lining, sleeving, milling and robotic operations. Less road opening, shorter schedules, limited disruption.
Our approach
A new pipe inside the old one. Without opening the street.
Renewing a buried network by open trench means opening the road, diverting traffic and immobilising a neighbourhood for weeks. Trenchless rehabilitation offers an alternative: renovating the pipe from the inside, working from the existing manholes.
SA LA GARONNE has made these techniques a distinctive part of its know-how. Continuous CIPP lining, sleeving, robotic milling, spot repairs: our crews and mobile units work on live networks, in the dense city centre as well as in outlying areas.
The result: a structurally new pipe, a service life extended by several decades, a shorter worksite and a road left intact.
The process, step by step
Rehabilitation without opening the road.
Trenchless rehabilitation renovates existing networks from the inside. Less road opening, shorter schedules, less disruption for residents.
Techniques
The processes we deploy.
Every network is different: the survey determines the technique best suited to the pipe's condition and the site constraints.
Camera survey — including the RIC, La Garonne's patented 4K 360° inspection robot — recording defects and measuring ovalisation and adverse gradients.
High-pressure cleaning of the pipe, removal of deposits, surface preparation before lining.
Removal of obstructions (roots, encrustation, intruding connections) by a milling robot operated from the surface.
A resin-impregnated liner, installed and cured in place: a new, continuous and watertight pipe inside the existing one.
Localised repair of a section or joint using a sleeve or short liner, without treating the whole length.
Robotic reopening of service connections after lining, reworking of joints and tightness testing.
Benefits
What the city gains.
- Road left intactNo trench along the route: the road, the pavements and the neighbouring utilities stay intact.
- Shorter schedulesOperations measured in days or weeks, where an open trench would be measured in months.
- Limited disruptionLess noise, dust and traffic diversion for residents, businesses and road users.
- SustainabilityA structurally reinforced, watertight pipe, good for several more decades of service.
- Controlled overall costLess excavation, backfilling and reinstatement: an optimised budget for the local authority.
Scope of work
Networks of every size, in every setting.
Sewer mains, service connections, structures: we match the technique to the diameter, the material and the condition of the pipe.
Technical data
Other expertise
Complete know-how across water networks.
Contact
A network to build, maintain or rehabilitate?
Let's talk about your project. Our teams give you precise answers, drawing on 70 years of worksites.