DOP Submersible dredge pumps

DOP350L eliminates chemical contamination

Project Summary

Location: The Ebro river near Flix, Tarragona, Spain

Period: Q4, 2011-Q4,2013

Challenge: Removing contaminated lays of top soil and a hard layer below

Solution: DOP350L, first with auger head then with cutter unit

Contractor: Canlemar S.L. as subcontractor for FCC S.A.

Wouter Beekman, Service Coordinator at Damen Dredging Equipment

“The solution of switching between the various possibilities of the DOP – with the auger head, the cutter unit or as a booster station – was the key factor to the success of the job”.

Years of uncontrolled production at a chemical plant had severely contaminated the Ebro River near Flix, Spain. The challenge was to remove the contaminated sediment without any turbidity and pumping it to a dewatering plant.

An overview of the pontoon based excavator with the DOP connected to its boom.


Two DOP pumps provided the solution. The first one, a DOP350L was fitted out with an auger head and attached to a pontoon-based excavator. The auger head cut away the layers of contaminated sand and silt with high accuracy - the excavator had been fitted out with NAVGUARD positioning and survey sensors and software.

The crane boom is fitted out wth inclino sensors for accurate dredging.


When the top layer was removed, the cutter unit replaced the auger head as a hard sandy gravel layer was to be removed. The cutter force was required to break the soil; the mixture was pumped to the dewatering plant making use of another DOP pump which was in use as a booster station.

The auger head is a compactly built unit.


Yet the contamination was even deeper, in relative coarse material containing large stones. Again, the dredge configuration was altered. The excavator was fitted out with its bucket, digging the stones out and dumping the material in a grit-topped barge. Larger stones were removed from the grid, all sand and gravel were pumped from the barge… using the DOP pump again.

DOP350L fitted out with cutter head working in a area that has been shielded off