As part of the restructuring of the Port of Hamburg, small, economically unviable harbor basins and sites have been transformed into new, larger sites suitable for container handling or logistics activities. For the first time in its history, the Hamburg Port Authority (HPA) has used dredged material originating from harbor basin maintenance works instead of sand to execute the large-scale development of such a construction site, the Dradenau logistics area. At a former storage basin for dredged material, a total area of about 8 ha was prepared for use as a logistics site.
For this purpose, approximately 250,000 m³ of stored silt were allowed to settle in the basin. A further 290,000 m³ of dredged material, which had been mechanically treated at the HPA’s METHA facility, were installed using a specially-adapted construction method. Instead of placing it in the designated landfill, it was possible to re-use the treated dredged material in a beneficial way, extending the useful life of the landfill by about two years. It was thus possible to save more than 500,000 m³ of sand / filling material, which generated a corresponding economic benefit for the HPA.
A sophisticated drainage system ensures that no pollutants, which may be washed out of the treated dredged material, are released into the surrounding groundwater or surface water. In order to pre-clean the pumped water before it is discharged, an iron-removal plant was installed on the site. The plant uses sand filtration, which needs neither chemicals nor energy. As a contribution to climate protection, a so-called methane oxidation window, one of the largest in the world, was built at the boundary of the area. This oxidizes the methane that forms in the subsurface by way of microbial reduction.
The first ideas for the project already existed in 2006, but it took until 2013 before construction of Dradenau logistics area could begin. At the end of 2017, the area was opened as a location for industrial enterprises. The final steps in its development are currently being completed. This successfully implemented new concept is a good example for future development measures involving large backfill volumes.