Deep Pit Shoring at Huntly Power Station

Dated: November 2009 Display all Projects
Principal: Genesis Energy
Distributor: Humes Pipelines
Contractor: PAE NZ Ltd
Product: DGECK Corner Slide Rail


In New Zealand pit excavations have traditionally been shored with sheet piling. This well proven method has the advantage of being able to be safely installed to significant depths to provide a secure working area. Unfortunately, the safety andconvenience comes at a price. Sheet piling is relatively slow to install, causes noise and vibration and requires special machinery. The installed cost is commonly in the region of $350 per square metre.

Contractors now have a choice. Trench Shoring New Zealand Ltd is a specialist company focussed on hiring out high quality shoring equipment from Krings International France. Designed and manufactured in Germany to exacting standards, Krings International France have a range of shoring from the small KVL trench boxes to the large Double Slide Rail Systems.

When it comes to the excavation of pits the DGECK Double Corner Slide Rail system is hard to beat. When one of the large 2400mm diameter concrete pipes carrying cooling water from the Waikato River to the Huntly Power Station recently sprang a leak the on site contractors needed to dig deep to quickly establish the cause of the problem and to undertake repairs.

Trench Shoring New Zealand was called on late one afternoon and by mid morning the next day the 15 tonnes of DGECK equipment was on site 100km from TSNZ's home base in Auckland. The job was complicated by a live water main crossing the line of the cooling water pipe at right angles. TSNZ configured the DGECK so that solid panels were on two sides and KKP Sheet Pile Frames and sheet piles on the other two sides. The use of the sheet pile guide frame and piles allowed the pit to be excavated safely while ensuring the integrity of the water main was maintained. By 4.30pm that day, the pit was excavated to approximately 3m deep with the DGECK system in place. Full installation was achieved early the next day.

The contractor used a 20 tonne excavator to dig the pit and together with a small on site crane to install the DGECK system.

The contractor PAE NZ Ltd, and the Principal, Genesis Energy, were impressed with the speed and safety of the DGECK system at a cost approximately half that of sheet piling.

For further information please contact Frank Swanberg, GM of Trench Shoring NZ Ltd on 021 944 632 or go to

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