Dewatering

Find Us

Zoom in on the map with the + button to see all location markers of Winstone Aggregates sites >

Close Map

Dewatering

To authorise various activities on site, the Three Kings Quarry holds a number of resource consents and permits. One Auckland Council permit authorises the take of groundwater by pumping from a bore that has been drilled below the site. Drawdown or lowering of the surface of the aquifer below the quarry floor enables efficient extraction of the scoria resource in relatively dry conditions.

The permit was first issued after a publicly notified hearing before, and decision by, ARC (now Auckland Council) as subsequently amended by Environment Court consent order 27 March 1997.

The permit was subject to a statutory and public review in 2003. This led to further amended conditions being confirmed by the Environment Court in July 2005.

Since the permit was first exercised, up to 5,000 cubic meters of water a day has been pumped, resulting in some 22 metre depth of groundwater having been drawn from below the quarry.

Dewatering is closely monitored through the Three Kings Quarry Monitoring and Contingency Plan (MCP) and Appendices (PDF 5.1 MB). These documents have been prepared in accordance with conditions of the consent and reviewed and approved by Auckland Council. Measurements taken and data collected for the MCP are reported to Auckland Council and the community through the Site Liaison Group. The data also shows that there are no adverse effects arising from dewatering.

If you experience difficulty downloading any of this information, please email us.