Swiss dewatering trial in Auckland cuts sediment landfill and carbon emissions from stormwater pond waste

Auckland Council is trialing a Swiss mobile dewatering plant on the North Shore to reduce sediment waste from stormwater ponds. The technology processes sediment on site, separating water, sand, and gravel. This cuts the volume sent to landfill by up to 60 percent and lowers transport related carbon emissions. The trial at Wairau Valley could reshape how Auckland manages the 14,000 cubic metres of sediment removed from ponds each year. The system extracts a higher percentage of dry solids than conventional methods, which typically only achieve 10 to 20 percent. Separated sand and gravel may be reused as fill or aggregate, and remaining silt can be used for topsoil. If the trial succeeds, it could reduce truck movements and landfill waste across the city. The Swiss Ambassador visited the site to observe the technology in action.