Surveying and Monitoring

As regular maintenance and relocation of sediment deposits are highly expensive, Port authorities seek more efficient solutions for reducing the costs and CO2 emissions of maintenance dredging. One solution, water injection dredging (WID), is carried out for maintaining the sediment deposits which predominantly consist of clay and silt. WID has been proven to be a cheaper solution by leaving the sediment in place, eliminating substantial costs for relocation of the dredged sediment.

Winning co-author Liesbeth De Keukelaere the Young Author Award, an article about the pilot test case organised at the Prins Hendrik Zanddijk project in Texel, The Netherlands, demonstrating drone technology for water quality monitoring.

IADC’s Young Author Award winner François De Keuleneer and co-authors Joris de Vroom and Arjan Mol discuss the Workability Tool which ensures captains of specialised vessels can make informed decisions to dredge during favourable wave conditions.

Dredging activities often result in the suspension of sediment into the water column in the vicinity of the activity. Sediment release to the aquatic environment and the effects of this release are often the prime environmental concern associated with dredging.

The continuing surge in vessel sizes is putting increased pressure on port authorities worldwide. Experts recount the implementation of innovative modelling for maintaining channel depths at the ports of Brisbane and Geelong, Australia.

To show the success of polymer use in highly contaminated areas, two recent projects are presented: at Port-La-Forêt harbour in La Forêt-Fouesnant, France and at the Kishon River seven kilometres downstream from Haifa, Israel.

Randle Reef at Hamilton Harbour, an Area of Concern (AOC), is the largest site in Canada contaminated with Polycyclic Aromatic Hydrocarbons (PAHs). A collaboration of municipal and federal entities is working on remediation measures.

Multicopters, unmanned aerial surveyors, can fly and take pictures in difficult-to-reach or potentially dangerous areas, improving the speed and safety of acquiring data.

TNO’s acoustic surveys of dredgers during all phases of the dredging cycle showed that permanent hearing threshold shift was not exceeded in any cases studied or in any species in question.

Removing sediments with high dioxin concentrations requires extra care, with modern surveying and tracking techniques from beginning to end, from dredging to a high-tech dewatering process to the final disposal.

A review of survey and monitoring techniques as well as specialised environmental systems are realised in an "ideal" vessel.

“Facts About Underwater Surveys” describes why surveys are crucial to a well-executed dredging project and the technologies and instruments being used.

The Fact Sheet "Environmental Monitoring” describes the methods used to alert dredging contractors to environmental impacts so they can be addressed quickly.

IADC presents a series of interactive free live webinars with experts from the dredging sector. Topics discussed are all based on high-profile projects.