New trial dike on the Dollard

The Hunze en Aa’s water authority and Ecoshape recently built a 40-metre-long test dike in front of the sea dike on the Dollard.

For the construction of the test dike the contractors used clay taken from the clay ripening plants that processed sediment from the seaport channel of Delfzijl and the Breebaart polder.

This is the first use of the material – clay ripened from salty dredged sediment – for dike upgrades.

Researcher Wouter van der Star explained: “The idea behind the trial was to demonstrate scientifically that a safe dike can be made using material available locally.”

The construction of this test dike is part of the ‘Broad Green Dike’ demonstration project. The test dike will deliver knowledge needed for the proper construction of the ’Broad Green Dike’.

The contractors are building with dried sediment from the Eems-Dollard. The material comes from two locations: the seaport channel of Delfzijl and the Breebaart nature polder.

The large-scale use of sediment from the Eems-Dollard reduces the turbidity of the water there, improving the ecological quality.

The Clay Ripener EcoShape project comes as a partnership of: the Dutch Flood Risk Management Program (HWBP), the Wadden Fund, the Province of Groningen, Groninger Landshap, Groningen Seaports, Rijkswaterstaat and salt-marsh owners.