BT LIFT & SHIFT PROJECT
Background
Ringway was due to redevelop Water Gardens South car park in Hemel Hempstead for the local council. A new access road was being installed from Leighton Buzzard Road into the car park to reduce traffic build-up. The area was cleared of trees and ready for the new road and Ringway carried out several trial holes to confirm the location of the existing BT ducts. 18 clay ducts were uncovered with only 400mm of cover to the top ducts. Due to the new road location these ducts
needed to have 1.3m of cover to ensure they were below the makeup of the road. BT were unable to lower the ducts for 10 months and the cost was over £1 million.
BENEFITS
- Cost saving of over £500,000 to the client
- Specialist trenching skills from THB
- One happy client!
BEFORE
AFTER
Objectives
THB were asked if we could lover 70 metres of the ducts due to our experience in Telecoms work, with BT supervising the work.
Challenges
- Delicate lift and shift without damage to the existing cables
- Locating existing BT ducts
- Soil excavation without damage to the cabling
- 6 week timeframe
Outcome
The existing ducts were marked out by THB’s cable tracer and a trench was excavated on either side. The top of the ducts were then exposed and timbers installed over the top. Ratchet straps were then used to support the bundle of ducts before the remaining ground was excavated from beneath the ducts using a Vacuum Excavator. Shrink wrap was used around the collars on the ducts to hold them together. Chain blocks were then added to lower the ducts to the required depth. Trench support was removed and the trench was reinstated ready for the new footpath and road construction to commence.
