The Koningsvijvers form a connected chain of 12 ponds. The source region of the river IJse runs through it and feeds this system. The ponds are therefore not only scenic, but also possess cultural and natural value (Natura 2000). To date, rainwater running off the surface of the Brussels ring road is routed directly to the ponds, though that is about to change.

Currently, much of the drainage at the intersection of the ring road (R0) with the E411 ends up in pond number 5 (photo).

Location roadwater purification
Vijver 5 / Etang 5 / Pond 5 created by dji camera

Investigations have shown that this rainwater running off the road is not completely pure. In addition to oil, suspended matter, together with heavy metals and poly-aromatic hydrocarbons (PAHs), are the main source of pollution there.

That is why part of the pond is going to be converted into a treatment basin. The solutions that have been devised are primarily aimed at removing suspended solids and the pollutants bound to them. The technical plans were prepared by the Flanders Environment Agency as part of the LIFE Belini project. The effective implementation of the project is expected to take place in 2025, thanks to a collaboration between the Agency for Roads and Traffic, the Agency for Nature and Forests and the Province of Flemish Brabant with co-funding from LIFE Belini.