International Dredging Review

International Dredging Review

By Marsha Cohen
After completing sea trials in late July in Shanghai a Damen trailing suction hopper dredge (TSHD) 650 sailed on her own keel to Australia to its new owner Gippsland Ports. The trailer named Tommy Norton is the first Damen Shipyards Group dredge built for Australia. She is specially designed for maintenance dredging and has an overall length of 60 meters (196 feet) and a width of 12 meters (39 feet) and a draft of 2.3 meters (7.5 feet). Gippsland Ports’ designated waters stretch over 720 kilometers (450 miles) along the southeastern coastline of the state of Victoria going from Anderson Inlet to Mallacoota which are south and east of Melbourne the capital of Victoria.
The new dredge will be used for maintenance of ocean access to the Gippsland Lakes. Construction commenced in June 2016 with the keel laying in September 2016 and launching of the vessel in April 2017.  She was then moved from the shipyard in Yichang China 1700 kilometers (1056 miles) downstream on the Yangtze River to Shanghai where sea trials were conducted in the East China Sea. After completing sea trials the TSHD Tommy Norton crewed by a seven member team from Damen left Shanghai on July 14th for a trip of approximately 5000 nautical miles. En route she stopped in Guam for bunkering and to take on fresh water and food supplies. Traveling at a speed of about 8 knots the dredge arrived at her destination August 31. 
For the voyage to Australia Damen’s team made extensive preparations to ensure that sufficient supplies were on board for the crew that everyone was familiar with the vessel and that all safety measures were well known. According to Captain Martin van Krieken safety is the highest priority during these preparations. This includes establishing both International Safety Management (ISM) and an International Ship and Port Security (ISPS) systems both of which have been certified by Bureau Veritas prior to departure. A number of safety drills were rolled out including abandon ship man overboard fire emergency steering collision oil spills grounding and piracy.
The team also has a comprehensive set of medical equipment and medicines in case of injury or sickness on board. In addition as captain Van Krieken is trained to administer treatment for most common medical situations and he can also count on the assistance of the Netherlands’ 24-hour doctor support service for Dutch Captains. In case of a medical situation occurring these qualified professionals judge if treatment is necessary and what form it should take.
The Tommy Norton will be operated by Gippsland Ports and will be based at Lakes Entrance position halfway between the outermost two points that fall under Gippsland Ports jurisdiction. In preparation for the delivery of Tommy Norton Gippsland Ports implemented infrastructure works to accommodate the new dredge 
and to provide necessary on-shore services and operational support. Included in this work on Bullock Island is an extension of the sewer main to provide for the vessel to connect to the reticulated sewerage system improved fendering and mooring bollards upgrading of the shore power supply at the wharf face installation of a concrete slab with collection pit and triple interceptor for refueling construction of a shed for dredge maintenance spare parts and equipment storage and bunded lubricants storage container together with upgraded data connectivity and security cameras. In addition Gippsland Ports is currently recruiting crew for the Tommy Norton which will have a complement of four when operating at Lakes Entrance. 
According to Damen to meet the demands of dredging at the Lakes Entrance the TSHD 650 has been modified to increase the installed propulsion power allowing her to manage the strong currents encountered in the harbor’s entrance. To minimise disruption to the local ecosystem an anti-turbidity valve has been fitted on the overflow to reduce air bubbles and visible plumage in the water. Additional features include an indication package to measure soil density. This allows the suction pipe to be angled precisely for accurate operations. The dredging process will be made even more efficient by the installation of the navigational dredging aid NavGuard indicating the area and quantity of substrate dredged. 

The Tommy Norton is capable of dredging to depths of 15 meters (almost 50 feet) the dredge has been built with self-emptying capabilities with bottom doors for discharging and the choice of either a bow connection or rainbow expulsion for beach reclamation work. In order to increase the vessel’s payload capacity when dredging sand with a high specific density Damen has reduced the freeboard of the vessel and applied a dredge mark.
Now that the vessel has arrived at Lakes Entrance final acceptance dredging trials will commence prior to Gippsland Ports accepting formal delivery from the Damen Shipyards Group. Following formal delivery Damen will provide Gippsland Ports’ crew with intensive training on the operation of the vessel. In preparation for delivery of the Tommy Norton a number of Gippsland Ports’ personnel are undertaking intensive training at Smartships Australia utilising a simulator which provides simulation of the Tommy Norton operating at Lakes Entrance. This highly sophisticated technology provides realistic operation of the vessel under a variety of weather tidal sea state loading and propulsion conditions. This not only provides development and assessment of operator competence in a simulated environment including emergencies such as loss of power or steering but allows development of passage plans standard operating procedures and emergency response plans prior to delivery of the vessel.
The new trailing suction hopper dredge replaces the New Zealand-based dredge Pelican operated by Van Oord. The Pelican has performed contracted dredging services on the Lakes Entrance bar for the past eight years. The Port of Gippsland Lakes is home to Victoria’s largest commercial fishing fleet. It also services commercial vessels and offshore oil and gas suppliers.
Maintenance dredging at Lakes Entrance has been undertaken for the last 120 years and is vital to provide a reliable entrance to Gippsland Lakes. Delivery of the Tommy Norton will ensure that ocean access at Lakes Entrance is maintained for the region’s economically important commercial fishing and tourism industries and this maintenance will also contribute to enhanced maritime safety for recreational boating and fishing enthusiasts using the entrance.
Up to 200 vessel transits per day of the entrance have been captured on Gippsland Ports’ web cameras which indicate the popularity and regional importance of this ocean access facility.
Maintaining ocean access will also decrease the risk and severity of flooding for local communities at Lakes Entrance Paynesville and Metung and the surrounding agricultural regions