THE FIELD WORK COMPONENT of an extensive geotechnical investigation programme for the proposed Project Aqua scheme in New Zealand is nearing completion.
Meridian Energy, the developer of the project, says the information gained from the geotechnical work is being used to update a detailed longitudinal section of the full length of the proposed power canal route. The investigation included 240, 100m diameter drill holes – extending to depths ranging from 15–60m. Additionally 430 test pits, each 3–5m deep, were also excavated to investigate the subsurface conditions. The field work mainly aimed at identifying the types and properties of subsurface soils, particularly pervious materials and the underlying rock formations. The holes and test pits will also provide records of the groundwater levels in the lower Waitaki Valley which can be expected to be encountered during construction.
The information is needed for the detailed design of Project Aqua and to prepare cost estimates for the proposed scheme. While the majority of the laboratory results of the soils have been conducted already, testing is expected to be completed by mid-February.