Island for migrating birds created using DOP250

The Haringvliet – a large water body just south of Rotterdam – was closed off the North Sea in 1970 to protect the Low Lands. Fierce storms from the North West had created huge damage a decade earlier, and closing off the estuary seemed the only choice. Over the years the water turned from brackish to fresh, changing the wildlife habitat drastically.

Recently, the locks - which have remained closed for decades - have been opened partially. As a result the tidal movement has returned, and the water will turn brackish again. The main reason for opening the sluices is the improvement of the water quality and the altered pattern of silt deposition.

The now brackish Haringvliet required adaptations for the wild life. The area is reknown for the large flocks of migratory birds stopping over on their journey from Northern Europe to Africa. For these birds a new stopping-off point has been created : an artificial island as a bird sanctuary.

For newly created island 5.000 m³ of coarse sand had to be transported. This new island is located in a very shallow area the sand barges could not reach due to their draught. The creative solution was using a DOP250 submersible dredge pump to bridge the gap.

The DOP250 was connected to a pontoon-based Caterpillar 374D LRE excavator. A carousel of sand barges was moored alongside. Sufficient transport water was added to the cargo, creating a mixture which could be pumped out easily.

The DOP250 was lowered into the sand cargo, emptying the barge and pumping the coarse sand over some 300 m to the new isle through a Di 250 mm pipe line.

The new island will create a safe habitat in the dynamic tideland.