Part 1 of this article was originally published in edition 43 of Port Technology International and is available for download here.
Misunderstandings about dredged material abound: “It’s dirty.” “It’s a waste.” “Dump it, but not in my backyard!” In an effort to create clarity about the characteristics of dredged material and how it can be used to improve our environment, the IADC continues here with part 2 of its question-and-answer narrative.
How can the supply of dredged material be matched with a demand?
Finding a supply of dredged sediment that matches the needs of a nearby construction project is no easy task. Matching supply and demand requires an overall management strategy at the earliest possible moment preferably during the project design phase. Mechanisms to coordinate linking a supply with a demand, to create a connection between the customer for a potential use and the supplier of dredged material, requires careful preparation.
One such mechanism that has been successfully applied is a specialised, so-called “incentivising” contract. This contract establishes incentives for the dredging company itself to seek opportunities for potential uses. The essence of such a contract is to provide positive outcomes for the owners of the dredging project, the construction users and the dredging company. To be most effective, the terms of the contract should be known prior to the tendering process.
What issues need to be considered when matching dredged
material with a use option?
Several critical issues to consider when trying to match a specific dredged material with a potential use option are:
• The quality and sufficiency of sediments is crucial. Is the material physically and chemically suitable? Is it environmentally acceptable? Will there be enough suitable material available?
• The time frame of both the dredging project and the use destination must be coordinated. If they are not concurrent, are there interim holding areas for the sediment whilst waiting for a particular use? Or does the timing of the dredging project need to be adapted. Can or should the start of the project be delayed or pushed forward?