When we got the call from Wellington Water to urgently stabilise a sinkhole that had appeared in a public park, we shored up the hole and found that it was caused by a collapse on a stormwater system constructed before 1900. Investigation showed that 50m of 525 diameter earthenware main at over 8m deep under Grosvenor Terrace was at immediate risk of collapse.
We looked at the options with our customer and settled on an ambitious plan to pipe burst and replace the affected section. If we could pull it off, then a pipe burst would deliver excellent value for money and programme savings all while addressing many of the risks associated with excavating a deep trench in a tricky location, around mature trees and under a live arterial carriageway.


Bursting on this scale is not to be underestimated. The team on site carried out meticulous planning and considered the contingencies we could put in place to make sure we were 100% ready before we started bursting. On the day things could not have gone better. It was a joy to monitor the slow and steady progress and see the burster and pipe arrive at the receive pit.
Trenchless solutions, like pipe bursting, can deliver “kick ass” outcomes on reactive and planned renewals when they are applied appropriately.