Tuai Penstocks Pile Supported Foundation
  • 1
Client: Genesis Power Ltd
Sector: Infrastructure
Contract Value: $1.4m
Completed: Nov 2009
Main Contractor: Brian Perry Civil


The penstocks feed the power station at Tuai for the Waikaremoana Hydro Power Scheme.  An ongoing land slip required a portion of the penstocks to be supported by piled foundations.

Work Scope involved:

Construction of 12 No. 1.2m diameter and  4, 900mm diameter reinforced concrete piles.  Works undertaken included using the Lodrill drill rig, an excavator mounted drill rig capable of drilling piles on a slope.

Construction of the reinforced concrete supports under 8 No. of the foundations and demolition of existing supports.

All excavation, piling and concrete work undertaken in and around the live penstocks containing high pressure water.

The project site contained lead contaminated soils caused by the degradation of original lead paint used initially on the penstocks.

The site was environmentally sensitive as it was directly upstream of Lake Whakamarino.