Winstone Aggregates has won a major contract to supply bulk aggregates to Auckland's State Highway 20 to­ 1 project. Part of the Western Ring Route, the NZ$210 million project connects State Highway 1 at Manukau with State Highway 20, providing an alternative route north to Albany.

Over the next two years, Winstone Aggregates will supply approximately 260,000 tonnes of aggregate including 102,600 tonnes of specialised Cement Treated Basecourse (CTB). This is the first time that such a large amount of Hunua CTB has been used by Transit on a major New Zealand motorway.

Winstone Aggregates produces CTB in high intensity mixing plants, blending cement and water with natural crushed basecourse (GAP 40). The use of a computerised control system enables a uniform dispersion of cement and moisture and ensures a consistent product.

 Key Facts:

* 4 lane motorway with provision for a 3rd lane to be added to each side in the future

* 4.5km in length

* Thirteen bridges

* 268,000 m2 of pavement

* 140ha site area

* 920,000 m3 of earthworks

* Construction completed by December 2010