McKay and MGE have completed electrical infrastructure work for Watercare's upgraded Clarks Beach Wastewater Treatment Plant, supporting its advanced treatment systems.
The project centred on two fully containerised switchgear cabins, prepared at McKay's Hamilton branch before being transported to site and connected to the plant's electrical systems. During a six-week fit-out, the cabins were integrated with MGE switchboards and PLC cabinets.
Once installed, the two units serve as switchboard rooms and function as the site's electrical hub, supporting the systems used to treat and manage wastewater for the Clarks Beach community.
The upgraded plant is designed to treat more than five million litres of wastewater a day. Electrical and mechanical work was completed to cold commissioning, allowing the site to move closer to full operation.
Container build
The project used two custom-built 40-foot containers adapted as switchboard rooms. Each was fitted with exit doors to Watercare standards and in line with AS/NZS 3000:2007, while the walls were lined with poly panelling for thermal and acoustic insulation.
McKay also reinforced the floors to support the weight of the switchboards and installed internal lighting, including emergency fittings. Cable ladder containment was added inside the containers to support wiring systems and provide access through the switchboard rooms.
MGE, McKay's switchboard manufacturing business, built the switchboards as MGE NZ Powerak boards to Watercare standards. The equipment included main switchboards, motor control centres, PLC cabinets, and distribution boards.
The layout was designed to fit within the dimensions of the two containers. The main switchboard distributes power to two process switchboards, which oversee and control motor-driven equipment across the site.
Control systems
Multiple PLC cabinets were installed as part of the plant's control system. They coordinate plant processes and form a central part of day-to-day operations.
The installation also includes variable speed drives for motor control and a UPS system to keep critical instruments and equipment operating during a power outage. These elements were included to reduce electricity use and maintain continuity for essential systems.
Logistics challenge
Installing the switchboards required a multi-person team to lift and manoeuvre each unit into the containers before anchoring and bracing them for transport. After the off-site fit-out, the containers were moved to Clarks Beach using a swinglift side loader.
A 100-tonne crane then lifted each unit onto its final supporting structure at the plant. The off-site prefabrication model reduced the amount of work required on site and helped keep the installation programme on track.
McKay works across infrastructure sectors in New Zealand, including water and wastewater, telecommunications, transport, and EV charging networks. The Clarks Beach project adds to its work in essential services, where prefabricated electrical systems are increasingly used to simplify deployment at operating sites.
Watercare's upgrade at Clarks Beach is intended to support a growing local population while maintaining environmental treatment standards. The plant's new electrical backbone is now in place to support the expanded wastewater treatment process.