Northlake Bulk Earthworks Phase 1 & 2

Wanaka

Read more about our Environmental Award win here.

Location

Outlet Rd, Wanaka

Type of Contract

Measure and Value

Value

 $10.3 M + GST

Completion

August 2016 – December 2019

(original programmed completion date was September 2020, so early completion was achieved by Civil Construction)

Description of works

The object of the bulk earthworks phases was to re-contour the land ready for the civil infrastructure to be progressively constructed following the completion of each stage of the bulk earthworks.

EARTHWORKS SUMMARY:

✓        Strip topsoil: 182,500m3

✓        Cut unsuitable material: 42,000m3

✓        Cut to fill: 600,000m3

✓        Respread topsoil: 136,400m3

 

Track Record and Contractors Performance

Key challenges:

  • Deep excavations: Removal of the existing rising main along Outlet Road and install of new gravity line alongside. Excavations ranged from 2-4m deep within the existing road reserve.
  • The following areas were identified as requiring ongoing management and monitoring throughout the project:
    • - Surrounding buildings and neighbours
    • - Construction vehicles, visitor parking and site deliveries.
    • - Site access & fencing
    • - Pedestrians and cycle traffic in adjacent areas
    • - Noise & Vibration
    • - Dust, sediment/erosion control and vegetation
  • CCL has proved its ability when it comes to coordinating, collaborating, working, and managing many subcontractors doing different works on site throughout the years working on site.
  • Works were completed within the desired timeframes and budget, plus the relevant contract specifications and quality standards were complied with. The subdivision performed as expected on completion and continues to perform according to requirements.

Health and Safety

Serious Harm accidents: nil

Man Hours expended: circa 53,000

Serious Harm accidents requiring reporting to OSH: nil

Client

Northlake Investments Ltd

Engineer

Paterson Pitts Group │ Alex Todd │


Services provided

  • Earthworks
  • Project management

 

The project was one of the biggest within Northlake Subdivision, having a value of more than $7M.
The Phase 2 bulk earthworks were proposed over an area of approximately 43ha, requiring
1,082,000m3 total qty of fill moved. Initially, the project was programmed based on a duration of 2.5
years, but thanks to the efficiency of the team at Civil Construction, the works were constructed in 2
years, reaching practical completion in December 2019.


The project had some technical difficulties, such as in-situ materials encountered and the complex
environmental risks. Civil Construction proposed to trial the use of various dust suppressants to
mitigate the effects, ensuring maximum on-site effect specific to this site leading to best value for
money for the Principal. Erosion Control – this was a big learning curve for all as this site was one of
the larger earth worked subdivisions undertaken in the Southern Lakes which created its own inherent
issues. Civil Construction worked with our engineers and engaged third party professional advice to
strategically implement silt detention ponds and forebays and use of flocculant. In-depth analysis of
positioning the silt detention ponds for later use within civil works minimised future expenses.
Another innovative approach was the straw mulch application, investing into new modern and
efficient plant to primarily minimize silt migration, with the bonus of inhibiting grass growth and
assisting in dust mitigation.


Civil Construction were very professional through the duration of the Contract, constantly monitoring
the quality and safety aspects. They always followed industry best practice and did not doubt
themselves in seeking for external advice when required to ensure risks were successfully managed
and no issues would arise. It is also worth mentioning their effectiveness and professionalism working
in such a complex site with plenty of neighbouring properties and other parties present. Regarding
the environmental approach, it was a clear demonstration of their collective skills, capabilities and
commitment to smartly overcome any challenges and achieving great outcome.


Marc Bretherton

Marc Bretherton

Client Representative, Winton Partners