Cardboard guide wall for Wellington pump station

An environmentally friendly cardboard guide wall proved successful at BPC’s Taranaki Street Pump Station project in central Wellington.

With the team required to shoot piles to a depth of 17m below ground, a guide wall was needed to provide the interlocked structure. Polystyrene former blocks would normally be used, but BPC’s team were committed to developing a more sustainable alternative. The option they settled on was using large Sonoco cardboard tubes, traditionally only used for casting above ground piles.

The cardboard tubes were more challenging to manage than polystyrene, but the team’s commitment saw them successfully delivered. Waste was kept out of landfill, replaced by a renewable alternative.

An additional benefit for the client was the cost-effectiveness of the sustainable approach.

The Taranaki Street pump station is 10.88m external diameter, 8.66m internal diameter, with a floor level approximately 8.5m below ground. To construct this, BPC installed forty-two 900m diameter secant piles 19m below ground level to form the new pump station’s superstructure.