After a lot of planning and complex excavation works Victory Christian Church in Auckland will soon be transformed with a new foyer, new administration building, 347-space underground car park, landscaping above the carpark with planting and a children’s play area.

Digging down below the water table for the car park and unearthing toxic chemicals required main contractor Mainzeal to scour the world for a safety system that would protect workers, locals and the environment from hazards.

The church purchased the site in 1983 and occupied it with its existing building since 1986. Since then it had changed internal configurations but altered its appearance little. Plans have been a long while in the works for expansion at the site, and in October 2005 it began formal negotiations.

When the redevelopment designed by Jasmax and its Australian partner dKO is finished, the church’s new foyer will have four sets of double doors at its entrance, high ceilings and a 7m high glass wall looking out towards the waterfront showcasing the view. The foyer will be used a pre-event space for church services, shows and other events to be held in the church’s auditorium. With seating for 2650, it is one of the larger auditoriums in Auckland. Externally, the foyer has single lock Coloursteel on the walls and double lock on the roof. The administration building will have zinc externally that will contrast with the decorative paving on the ground.

Excavation posed untold hazards. It was expected that a chemical mystery lay underneath the ground because it had once been the location of the old Auckland gasworks and it was thought high levels of carbon monoxide would be found.

To stop contamination from the site leaking into the atmosphere when the church car park was excavated, Mainzeal needed to source a protective tent and filter system. Because this had never been done before in New Zealand, extensive research was required. The equipment was located in America and Australia. The air needed to be changed four times an hour to process the hazardous materials in it. The filter system consisted of two shipping containers converted with large fans that sucked out 12 litres a second through a dust extraction system and carbon filter system to clean the air of any volatiles, then the air was passed out into the atmosphere.

More than half the ground excavated turned out to be contaminated but aside from hazardous materials, relics left behind from old gasworks surprised workers at the site as they dug underground. Among the items they discovered underground were tanks still full of oil, old concrete bunkers that would have held coal, Victorian circular brick wells and chains from conveyor belts.

Between six and eight months of the total construction time was spent dealing with the environmental controls, odours and ground obstructions. Once the project is finished, from March 2012 the church will be transformed with its space suited to hireage for commercial events aside from its regular program of church uses.