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www.sea-technology.com March 2015 / st 17 N early all the major ports and waterways in the world have at some time required new dredging works (capital dredging) as technological developments and the require- ment to improve cost effectiveness have led to larger, more effcient ships and expanding coastal infrastructure, which more recently includes provisions for renewable energy developments. New port developments and expansion of current facilities (including larger and deeper access chan- nels, turning basins and appropriate water depths) are required along waterside facili- ties to accommodate these vessels. Recent examples include the London Gateway Port Development Project, the New Port Project in Doha, Qatar, the expansion of South- ampton docks in the U.K. and the devel- opment of the Port of Hastings in Victoria, Australia. Capital dredging projects can be both extensive and expensive. Many of these dredged sites later require maintenance dredging (removing any sediment that has accumulated in the bottom of the dredged channels and berth boxes). Maintenance dredging is necessary to maintain safe opera- tional water depths for navigation and to facilitate contin- ued access to berths, docks, wharves and jetties for the large vessels engaged in domestic and international commerce by ensuring that they are of adequate dimensions. Mainte- nance dredging is often a regular, perhaps annual, ongoing, long-term activity, but can also be required on an ad-hoc basis following storms or other hydrodynamic events. Why Do We Monitor? It is well understood that dredging operations can have signifcant negative impacts on the local environment. As a result of this fact, local government authorities stipulate that monitoring must take place as part of the process for issuing licenses for dredging and, as such, is a legal compliance issue. Responsibility for monitoring the impact from dredg- ing operations often falls to the dredge operators, including contractors, and data obtained from monitoring stations are usually shared with all stakeholders. Establishing Baseline Information It is necessary to obtain back- ground readings of water quality parameters (turbidity, tempera- ture, dissolved oxygen, pH, etc.), currents/tides and bathymetric data well in advance of the com- The Importance of Effective Dredge Monitoring Port Maintenance Dredging Essential for Continuous Safe Navigation By Dr. Richard Williams • Becky Childs (Top) CSD Dredger D'Artagnan in operation on the New Port Project in Doha, Qatar. (Bot- tom) OSIL 1.2-meter Tern Buoy performing environ- mental monitoring. (Photo Credit: OSIL) (Photo Credit: Mark Barham/Gardline)