Client name: New Zealand Retail Property Group (NZRPG)

Duration: May 2006 - ongoing 

Location: Westgate, Auckland, New Zealand

Coffey provided timely, smart solutions for the earthworks at Auckland’s new Westgate Town Centre Development – reducing geotechnical risk and project cost.

Developing a Town Centre on variable strength alluvial subsoils 

Westgate is a new regional town centre in Northwest Auckland – with an overall vision to be an integrated business and community area. On completion it will include precincts for a shopping mall, town square, civic buildings, offices, retail and public open spaces.

The area is characterised by variable strength alluvial subsoils and areas of organic subsoils. Our client, NZPRG, sought certainty that the land would be suitable for the proposed development, and confirmation that earthworks and building proposals were possible.

With a tight timeline between earthworks and construction, NZPRG required a timely and detailed assessment on the potential effects of fill and building induced settlements. This ensured the development would meet consent requirements.

Geotechnical investigation allowed development of precise ground models

We undertook a detailed geotechnical investigation including machine boreholes, hand auger boreholes, CPT’s and trial pits. This provided a clear understanding of ground conditions and allowed us to develop precise geotechnical ground models.

To assess soil conditions we carried out settlement monitoring of fill embankments and deep fill areas using settlement plates, markers and vibrating wire piezometers with appropriate trigger limits. Identified organic soils were removed where practical and placed in designated areas onsite within reserves.

Our investigation allowed us to provide achievable and suitable fill compaction control criteria for repurposing soil on site, in pond and road embankments, bulk fill and reserves. Earthwork costs were reduced and we successfully managed our client’s geotechnical risks.

Our regular participation in project meetings, site inspections and fill quality control testing ensured earthworks construction was undertaken to design specifications and quality assurance standards, keeping the project on track for completion. 

Timely and cost-effective settlement monitoring and soil disposal 

Our provision of ongoing advice ensured client confidence and certainty in development proposals. And our understanding of local ground conditions, led to smarter solutions in settlement monitoring and soil disposal – reducing cost and time.

Client testimonial

"I have worked with many geotechnical engineers over my 30 year civil engineering career and Coffey are second to none; competent and professional."

Derek Manning
Project Director
NZRPG Management Ltd.
New Zealand Retail Property Group