• Isolated work sites with minimal access in rough terrain
  • Very limited communications service
  • Extreme weather conditions
  • Delicate ecology and environmental issues
  • Working near live powerlines
  • Very unforgiving ground

Transpower Tower Foundation Strengthening Stage 1 to 4 (2005-2007)

This project won the 2007 New Zealand Engineering Excellence Awards Supreme Award. We are proud to have been associated with this project.

Project scope

This project involved upgrading the foundations on transmission line towers in the upper South Island. The route covered 450km of network with much of the line passing through the remote and wild high country from Hanmer to Saint Arnaud.

Griffiths Drilling played a major part in this undertaking and our part in the project included:
Drilling and fully casing the anchor holes in very unforgiving ground
Self drilling anchors
Passive anchors
Post tensioned ground anchors
Providing assistance to the grouting crew in loading anchors and the post construction cleanup.

Complicating factors and solutions

Isolated work sites, minimal access, rough terrain, very limited communications service, extreme weather conditions, delicate ecology and work near live lines all presented challenges that were overcome. This included our staff attending training courses by Transpower so they could safely work around the base of the towers, using satellite phones, careful planning and logistics and an awareness by the drilling team of all the environmental factors including the weather that could adversely affect safety or the outcome of the project. The judges of the awards were particularly impressed by the calibre of the technical and logistical management over such an extended site.


In his report to the Department of Conservation following an audit of the environmental impact and practices of the contractors on site, consultant Ian Alach noted, "Griffiths Drilling demonstrated great professionalism in their operation and seemed easily able to meet the conservation requirements". 


Generate New Image


This section highlights some key drilling projects that Griffiths Drilling have been involved in. It also includes 'Projects Since 1971' and 'Earlier Projects' pages to showcase our extensive history and experience within the New Zealand drilling industry.

Mackays to Peka Peka Expressway (M2PP)

This $630 million project will deliver approximately 18km of 4 lane expressway through Paraparaumu and Waikanae, including a new bridge over the Waikanae River. Griffiths Drilling has been part of this project from its inception.

Transmission Gully

Transmission Gully is the biggest road construction challenge in the Wellington region. We began exploration work in 2007 for Opus. Further work was undertaken in 2013 for MWH and NZTA, with detailed geotech investigations for Leighton Contractors and Coffey Geotechnical in 2014 and 15.

Tauhara Geothermal - Geotechnical Drilling Adviser & Consultant

Mel Griffiths was engaged by Contact Energy as the Geotechnical Drilling adviser for the Tauhara Geothermal Subsidence project.

Wind Farm

Limited access, steep terrain, wet slippery conditions and very high winds were complicating factors. Also the rock was very fractured due to the proximity of the main fault line.

Muldoons Corner

This is a difficult section of SH2 which needed realignment. It's located near the summit of the narrow Rimutaka Hill Rd and features tight corners, no shoulder and near vertical faces above and below the road.

Dowse to Petone

A $65 million road improvement carried out to enhance the traffic flow on SH2. Flexibility of resources was paramount on this project, which included 45 piles at 7 sites and a new service road, requiring soil nails.

Silverstream Landfill

A large landfill site serving two cities that required anchor and drainage holes in rows along the walls of the gullies. Communication was important as all work was done around the customers programme of concrete spraying.

Centre Point Wharf Piles

This project was carried out over water on a barge in the very busy Wellington Harbour. As if this wasn't enough, matters were further complicated as quality samples had to be recovered from very soft sediments.

Waiwhetu Stream

This project required 35 boreholes and 23 CPTs. Sites included working on the road for bridge pile information, open public areas alongside the stream and in the confirms of industrial operations and a Holiday Park.

Soil Nail Wall

Construction of a retaining wall that included drilling and testing a sacrificial nail for design purposes, drilling and installing production nails, fabrication of nail heads, fixing mesh to the face and applying sprayed concrete.

Projects Since 1971

A list of all the major projects undertaken by Griffiths Drilling since its inception. Work includes some of New Zealand's most challenging and largest drilling projects, including the Clyde dam, Wellington Motorway, Te Papa, Westpac Trust Stadium and the ongoing Transmission Gully work.

Projects from 1948 to 1970

Projects completed before Griffiths Drilling became an official business. They show the experience that is inherent in our drilling business today. Work includes Waikato, Waitaki, Roxborough and Cobb Valley dams, Tongariro Power and Wairakei Geothermal projects along with others.

Water Bores

We have well over 40 years experience in drilling water bores. Most have been carried out in the Wellington, Hutt Valley, Kapiti Coast and Wairarapa regions, giving us an unequaled and comprehensive knowledge of the ground aquifers within these areas.