Client: Transit NZ
Contract Value: $8.6M
Contract Period: 10 Months
Consultant: Beca Carter Hollings & Ferner

This project involved construction of the motorway in a very difficult terrain as well as handling very soft and sensitive soils. Earthworks on this project consisted of cut in excess of 40m deep and fills over 20m high. The total cut to fill volume was about 900,000m3.
The main cut contained a core consisting of approximately 50% Waitemata series sandstone, which varied from weathered and soft to R2 material requiring drilling and blasting. Most of the remaining cuts and capping material was extremely soft and generally needed extensive drying and needed to be blended with better Waitemata series sandstone to be able to be placed in the fills and achieve the required compaction standards. This required difficult cutting processes and careful monitoring of the fills. Special care needed to be taken with the Waitamata series sandstone as it quickly deteriorated with any water. This sensitivity of the Waitemata’s made the placing and blending with wetter materials very difficult.
To achieve the programme sufficient resources were mobilised and the average production rate was 170,000m3 /month.

Location: Auckland
Principal:Watercare Services Ltd
Contract Value: $7.8M
Completed:March 2004
Consultant: URS

This project is a Joint Venture between McConnell Dowell and Ross Reid Contractors

This contract involved the removal of 230,000m3 of constructed earth dam, placement of this material in a storage area, maintaining separation of the individual filling types and conditioning wet materials excavated from perched water table areas. To achieve this, the JV developed a haul road made over extremely soft underlaying sediments and created a dry, clean storage area, in a tributary of the dam. To create the storage area the JV displaced some 10,000m3 of very wet silt and piped the ributary. This was a contractor innovation that has handled 60mm rain events and saved both time and money. The majority of the excavation was removed using CAT 631 motor-scrapers and the material was carted up a 1:7 haul
road to the storage area. At the base of the dam, the JV undertook rock cleaning and commenced reconstruction in zones with the placing of 14,000m3 of specially graded filter and drainage materials along with the zones of cove and shoulder. Compaction during backfill has been critical not only to achieve a good density but also to ensure that over compaction of fill occurred. McConnell Dowell was responsible for the “structures” on the project comprising a replacement access bridge and the strengthening and refurbishment of the Valve Tower.

Principal:Kiwi Properties
Contract Value: $ 28 M
Contract period: 22 Months

The works involved site works for a shopping complex development over a 22 hectares site.

Earthworks- involved cut to fill about 20000m3, cut to waste about 80,000m3. The subgrades were very weak and required significant reconditioning /improvements.

Structures- works involved construction of 500m long , 4.5 x1.5 and 3x2m precast culvert units. Insitu concrete transition structures were constructed at several places i.e. bends, inlets and outlets. Significant sheet piling works and dewatering works were carried during construction. The existing Stormwater system was maintained right through the construction period.

Pavement and Surfacing - The project works involved significant pavement works they include- : Bascourse construction for buildings -80,000m2, Pavement & surfacing -100,000m2.

Drainage: stormwater -8500m of 225mm to 1800 dia Stormwater pipes to a maximum invert depth of 4.5m. Sewer reticulation - 2500m of 150mm to 375mm pipes.