Our WorkTrenchless Drain Repair at Exeter University

Minimal disruption. Maximum results.

The Challenge

Exeter University discovered major root intrusion in a 225mm clay surface drain running beneath an area of natural beauty with large trees and protected wildlife. With only one week before reopening, traditional excavation was not an option — it would have caused significant disruption to the landscape and the university grounds.

Our Solution

Flux Sewer provided a trenchless drain rehabilitation service using the latest technology:

Robotic root cutting to quickly and precisely remove large tap roots from the pipework.
A full pipe cleanse to restore flow and prepare for lining.
Installation of a Bluelight cured-in-place pipe (CIPP) liner (225mm x 4.5mm PAA-F) to prevent root re-entry, strengthen the pipe, and improve flow performance.

The Results

✅ Over 100 metres of drainage rehabilitated across three sections
✅ Zero disruption to the trees, wildlife, and natural environment
✅ Pipes now have improved structural integrity & flow
✅ Project completed within the one-week deadline

Mass Root entering

Tree and shrub roots naturally seek out moisture and nutrients, and sewer or stormwater pipes are an ideal source.
Any cracks, loose joints, or porous sections in the pipe allow fine roots to penetrate.
Over time, the mass of roots grows inside, forming a root ball or mat that restricts water flow and traps debris, eventually causing blockages.

Large Tap Root

Size & strength: Unlike fibrous roots, a tap root is thick and rigid, capable of physically breaking or displacing pipes.
Source tree: Likely from a large nearby tree (oak, maple, poplar, willow). These roots can continue expanding and cause recurring damage.
Flow restriction: Even if partially removed, the opening allows repeated invasion.

Some of the roots removed from the pipework

Utilising Light

nstead of ambient cure or hot water/steam cure, the liner is cured using specialized LED bluelight technology.
The LED system cures the liner uniformly, quickly, and under controlled parameters, significantly reducing risk of under-curing or weak spots.