Scheldt river: Hedwige Prosper restored wetland demonstration site

To protect the hinterland from flooding and to boost valuable nature, wetlands are restored along the flanks of rivers and estuaries. River currents and tidal flows create a unique tidal environment that accommodates rare plants and animals. Due to the restoration of natural processes, wetlands can adapt to sea level rise and, as such, contribute to flood risk reduction under future climate change scenarios.

The Hedwige-Prosper has been re-connected with the Scheldt river in 2022. Almost 500 hectares of new intertidal area was created. The area was transformed as part of a nature compensation scheme and contributes to the European conservation objectives (N2000 & WFD).

The Hedwige-Prosper area is located close to the Antwerp harbour including major industries. PFAS in the Scheldt is a major environmental problem, mainly caused by discharges from the American chemical company 3M near Zwijndrecht (Belgium) into the Scheldt, which led to high pollution levels in the Western Scheldt. This raised concerns about the safety of fish and bathing water. Although measurements have been taken and the Zeeland Public Health Service (GGD Zeeland) considers swimming at official locations to be safe, political debates and legal proceedings are underway to address the source and reduce emissions, because PFAS substances accumulate in the environment.

Fine sediments such as silt and clay accumulate in wetlands due to the reduced flow velocities. This sedimentation ability allows wetlands to adapt effectively to sea level rise by the process of land level rise. However, aquatic pollution such as PFAS, heavy metals and plastics typically attach to fine sediments. It is therefore hypothesized that restored wetlands nearby pollution sources perform as important sinks for a wide range of pollutants. How different pollutants are distributed and accumulate in these restored natural areas is however largely unknown and requires detailed monitoring.