Challenges

Smart options for using dredged sediments from Amsterdam Sustainability



Background:

Together, the Port of Amsterdam, Waternet and the city districts of Amsterdam dredge some 20,000 to 30,000 m³ of sediment per year in Amsterdam. Most of the dredged material is removed and disposed of elsewhere or put to low-value use. The question is, are there promising and high-quality applications for dredged sediments from Amsterdam?

Some of the dredged sediment is chemically contaminated and we do not regard this as usable. In the future, it is possible that products could be made from contaminated, dredged sediment using, for example, a materials passport. In the meantime we refer to class A or B dredged sediments for the purpose of this call for proposals. In addition to clay and sand particles, this dredged sediment contains physical and chemical contaminants which are included in the sediment during the dredging process. The contaminants include refuse, plastic and similar materials, as well as micro-pollutants such as heavy metals and organic contaminants (oil, polycyclic aromatic hydrocarbons, etc.).

The Foundation for Applied Water Research (STOWA, the water boards’ research institute), in cooperation with the water boards, has developed a model to determine and assess the circularity score of dredging projects. Although the circularity model is currently formulated for a limited number of frequently used dredging chains, all submissions will be assessed according to the criteria of this model. The model can be found via this link: Circular dredging management, an assessment tool for regional dredging. Plus addendum Meadow Depot | STOWA (in Dutch).

All (local) government departments have set a target that requires 50% of their work to be circular by 2030 and 100% by 2050. This means that, ultimately, no waste will be created. Dredged sediment is one of the largest waste streams produced by water and harbour managers. The question is how this waste material can be used in the most sustainable and circular way.

Assignment for startups:

Develop a useful application for dredged sediment from Amsterdam, with the highest possible circularity score (see link in background).

Criteria:

The startup’s proposal will provide information on:

  • The cost of the product per m³ of in-situ dredged sediment.
  • The proportion of the dredged sediment actually applied, in mass % and volume %.
  • What to do with the unused part.

Issued by:

Waternet and the City of Amsterdam