Fremantle Highway on board Boskalis’ Boka Vanguard, heading to China on Thursday
The Fremantle Highway disaster ship is on board the semi-submersible heavy lift vessel Boka Vanguard of Boskalis. The ship will now slowly re-surface again. The cargo will then be sea-fastened, and the ship will leave for China this coming Thursday.
To get the Fremantle Highway on board, the Boka Vanguard first had to submerge. The ship has a maximum draft of 15.50 meters but can draw deeper if the ballast tanks are filled, causing it to disappear underwater. Last Sunday, the ship sank to a depth of 24 meters in 12 hours, with the loading deck about six to seven meters underwater.
To submerge the ship, the 93 ballast tanks were filled with water using four ballast water pumps, each capable of pumping 5300 cubic meters per hour. Together, they can pump water at a rate equivalent to filling eight Olympic swimming pools per hour. Only the four towers of the ship are still visible above the water of the Caland Canal, and the bridge is located on the forward tower on the starboard side.
The Fremantle Highway was towed on board, completely according to plan. The ship arrived on Monday behind tugs from Damen Verolme via the Nieuwe Waterweg in the Caland Canal. The same tugs, together with winches, then pulled the ship on board. A custom-made construction was made on the deck in advance to put the Fremantle Highway on the dry surface.
Pumps
The four pumps can both fill and empty the ballast water tanks, allowing the Boka Vanguard with the Fremantle Highway on board to resurface. The ballast tanks need to be kept partially filled. Additionally, the car carrier is not positioned in the centre of the Boka Vanguard.
The Fremantle Highway poses a relatively small and light load for the Boka Vanguard, which is the flagship of the Boskalis fleet. The ship has a weight of 17,000 tons, while the Boka Vanguard has the capacity to handle nearly 117,000 tons in theory. This has never occurred in the past. The highest weight transported was 92,000 tons, which was when the Boka Vanguard carried the Petrobras P-70 FPSO from China to Brazil.
The transport will depart for China on Thursday. The journey will last about 55 days. Upon arrival in China, the car carrier will undergo renovations and will then be put back into service under a different name and for a different owner. There is a high demand for car carriers in China. The Boka Vanguard will also undergo inspection in China and will be prepared for transportation from a large dry dock.
This article was initially published on Schuttevaer, Project Cargo Journal’s Dutch sister website.
