Monitoring Dredging Spill and Siltation
It’s impossible to dredge without spilling some part of the sediment into the water. Sediment spill may negatively affect the biota. Benthic filtering organisms are sensitive for sediment accumulation and elevated near-bed sediment concentrations. Benthic primary producers are negatively affected by a decrease in incident light caused by suspended sediment in the water column, while pelagic organisms may be directly harmed by it.
Dredging spill causes high near-bed turbidity, and sediment accumulation on the bottom, both of which may be measured using a SediMeter.
This example illustrates a project that involves dredging on a sand bottom and transporting the material to a beach. All bottoms around the site are sand, except the coral reef and seagrass bed indicated in red and green, respectively, on the map. There is also a navigational channel. Siltation is only a concern in those three areas. SediMeters are placed strategically so that the siltation can be estimated in all areas of concern. There is also a current meter, such as SediTrans, so the delay and direction from spill to impact may be estimated.
- Sediment spill can be monitored in a biotope by SediMeters
- The system can be networked so that alarms can be issued in real time