VESSEL REVIEW | Ursa – Shallow water-capable hopper dredger enters service with Polish maritime agency

The Maritime Office in Gdynia in northern Poland recently took delivery of a new trailing suction hopper dredger (TSHD) built by Finnish shipyard Tyovene. Named Ursa, the vessel was designed by Netherlands-based C-Job Naval Architects to also be capable of operation in both shallow and deep waters.

The Bureau Veritas-classed TSHD has a steel hull, a length of 62.75 metres (205.9 feet), a beam of 12 metres (39 feet), a draught of 3.9 metres (13 feet), a displacement of 2,341 tonnes, and a hopper capacity of 950 cubic metres (340 feet). Dredging can be performed at water depths of as low as 18 metres (59 feet). The dredging equipment supplied by Holland Marine Technologies includes a suction drag arm, hopper doors, and discharge pipes.

Ursa will be used to preserve the main 20-kilometre (12-mile) waterway between the Gulf of Gdansk through the Vistula Lagoon to the Elbląg River. It will also be used to maintain track depth parameters of smaller ports of the Vistula Lagoon as well as in the fairway from the newly constructed Nowy Swiat channel to the Port of Elbląg. This will permit safe passage to and from the port by ships measuring 100 metres (330 feet) long and with draughts of 4.5 metres (15 feet).

Versatile vessel with durable propulsion setup

“This vessel is the first dredger that we have worked with so almost everything about it is unique,” Tyovene told Baird Maritime. “For example, the hopper’s bottom doors, which can be opened to be able to release the collected sediment into the seabed, is a unique feature for this vessel type.”

Tyovene said the owner had crafted a pre-made construction specification that needed to be followed. The main particulars, the performance required of the vessel itself, and the expected performance of the dredging equipment (with regard to loading times, for instance) were already included in the brief. This then allowed the builder to know the owner’s requirements prior to the signing of the contract, and those specifications were fulfilled with some features even exceeding the owner’s requirements.

“The owner previously did not have any dredgers in its fleet, and so dredging works had been outsourced to specialised companies,” added Tyovene. “Since there are continuous dredging works going on nearly all the time, the owner decided to invest in a dedicated vessel and crew. In addition to being a financially more viable approach, it will also lessen dependence on third party dredging companies.”

Ursa utilises a twin-screw setup with two Cummins QSK19 diesel engines driving fixed-pitch propellers via ZF 3350 gearboxes. The propulsion setup was kept as simple as possible to ensure greater durability and reliability, as the TSHD will be operating in shallow and sandy waters. The dredger also boasts a vessel automation system and an automated dredging system.

Slated for future deployment at other local ports

The TSHD has its wheelhouse and accommodation placed at the front. This will ensure it can pass safely underneath the Trasa Unii Europeiskej bridge. The deck equipment meanwhile includes a Melcal boom crane, one aft and two foredeck anchors with windlasses and rope drums, folding fore and main masts, and a dedicated davit for use with a Viking rescue boat.

“It was interesting to see the various pieces of deck equipment work seamlessly together to ensure the success of dredging operations,” said Tyovene.

The newbuilding contract for Ursa was signed just before the war in Ukraine broke out, which then led to a number of issues. Tyovene remarked that this was especially true in the case of the costs of materials, the availability of manpower, and delivery times. All these factors were impacted but the builder still needed to make up for these somehow.

“The construction highlighted some key lessons,” Tyovene told Baird Maritime. “These included the importance of having a clear and effective plan as well as a schedule for system integration and communicating that plan to all parties involved. Also, communication between various parties, such as between designers and key component suppliers, will always have room for improvement.”

The Maritime Office in Gdynia expects to also utilise Ursa in other large ports such as Tolkmicko or Frombork.