Some 180k m3 of dredge spoil is being used as filling material in the construction of the Swedish seaport's brand-new terminal.
When the masses have been stabilized and solidified, and further surface works have been completed, 140k m2 will become available.
Construction of the terminal got under way in autumn 2018. Since then, 1,500 piles have been sunk into the bedrock, and the Arendal Bay has been embanked with blasting stones from an adjacent hill.
The embanked bay will constitute the coming terminal area. However, it has to be filled with the contaminated dredge spoil first.
When the material fills the basin, water is forced out and needs to be purified and checked before it is returned to the sea. "This is done by adding carbon dioxide to the water from the backfill basin, which lowers the PH value so that pollutants can precipitate. The water is then pumped on to a sedimentation basin and on to a sand and active carbon filter. We examine and send water for analysis once a week to ensure that the water is ready to be pumped into the sea," Kristina Bernstén, Environmental Engineer, the Gothenburg Port Authority (GPA), explained.
The terminal will have been completed by 2023, offering a total area of 220k m2 (plus an option to add 80k m2 in the future) and 12 m of water depth alongside the quay.
"The terminal is a crucial aspect of the port's long-term expansion plans and will further strengthen Gothenburg as the Nordic logistics capital. By almost exclusively using recycled material in the project, we are also able to expand with environmental consideration," Joakim Grenmarker, Project Manager, GPA, underlined.
Photo: Port of Gothenburg