Lake Dewatering Efficiency Project

Introduction

NZ Pump & Energy partnered with one of the largest manufacturers of concrete aggregate, sands, and roading materials in the South Island. Every couple of years, the client drains a naturally filled lake to excavate raw material—a process that needs to be carried out as quickly and efficiently as possible to maintain production schedules and minimise costs.

Solution

NZPE’s John Dutkiewicz worked closely with the site operations manager to set project timeframes and identify opportunities to reduce both dewatering time and fuel burn.

To deliver on these goals, NZPE supplied a tailored package of new Atlas Copco PAS 300 and PAS 200 pump sets, supported by a customised manifold system. This manifold was designed to connect with three fixed discharge polyethylene pipes, increasing discharge efficiency and reducing pumping time.

The results were immediate: the system delivered water 50% faster than in previous dewatering cycles. Once the lake reached the required datum, the pumps were automated to maintain levels consistently.‍

‍“We had the ability to exceed flows above 700 l/sec.” – John Dutkiewicz

‍The advanced equipment and automation freed up resources for other parts of the project, significantly improving productivity. NZPE also provided on-site support throughout the project, regularly reviewing changing requirements and adapting the pumping solution to keep aquifers manageable while maintaining cost-effectiveness.

Outcome

‍NZPE’s solids-handling, auto-prime pumps with GPS connectivity gave the client the added benefit of remote monitoring and proactive maintenance scheduling. This not only ensured equipment reliability but also gave the client confidence that the job was completed with maximum efficiency and minimal disruption.