Dunedin Airport Water Supply Project

Isaac Construction delivered the replacement of ageing water infrastructure at Dunedin International Airport—an important investment in the resilience and reliability of the airport’s essential services.

The project replaced a network dating back to the 1960s, strengthening the airport’s ability to operate safely in the face of climate, seismic, and operational risks. It forms a key part of ongoing infrastructure upgrades supporting both the airport and the wider region.

Scope of works

The project involved replacing ageing asbestos cement (AC) potable water pipelines, concrete reservoir and pump station with a modern, fit-for-purpose system.

Key elements included:

• Installation of approximately 755m of new potable watermains, ranging from 125mm to 250mm polyethylene (PE) pipework
• Construction of lateral connections to multiple airport facilities, including the Airport Fire Station
• Construction of concrete foundations for two 10.4m diameter, 350,000-litre stainless steel potable water storage tanks
• Construction and installation of a new pump station, including associated mechanical and electrical systems
• Installation of over 2,000m of electrical and communications ducting, integrated alongside pipeline works to maximise efficiency
• Reservoir and pump station commissioning and performance testing in line with NZ Drinking Water Standards.

Delivery in a live airport environment

Delivered within a busy operational airport, the project required careful planning and disciplined execution to manage risk and maintain continuity of services.

The team adopted a proactive approach to:

• Coordinating works around ongoing airport operations
• Protecting a complex network of existing underground services critical to airport functionality
• Maintaining safe access and minimising disruption to staff and passengers

A key requirement was maintaining compliance with drinking water standards throughout construction and commissioning. This ensured continuity of safe potable water supply for airport operations at all times.

Final commissioning was carefully staged to bring pipelines, reservoirs, and the pump station online without interrupting supply. All systems were successfully integrated while meeting required drinking water standards.

Award winning excellence

The success of this project was recognised at the 2026 Otago CCNZ Awards, where it won the Category C Projects ($1–$5 million) award.