Posted on April 29, 2021
Planned for completion mid May was maintenance and the technical overhaul of a 2,200 ton inner gate on Bremerhaven’s Kaiserschleuse ship lock, reports Tom Todd.
Lloyd Werft Bremerhaven, which has often carried out similar complex Kaiserschleuse lock work in the past, also tackled the latest job. Marketing Head Marco Graudenz told Maritime Journal “the work was completely normal: nothing unusual to report”.
The giant 57m long, 23m high and nine metre wide gate was towed across the Kaiserhafen and into LWB’s Kaiserdock 1 in April by a floating crane after the water in the harbour was raised.
Before the gate could be lifted from the Kaiserschleuse, silt had to be removed from the tank lid and water pumped from its ballast tanks. Port officials said the operation was “literally a matter of millimeters” with just 67mm of space available to manoeuvre the gate.
Along with maintenance, “technical overhaul works” were also being completed at LWB. Reports linked that work to earlier construction flaws which have dogged the new €230 million 305 x 55m Kaiserschleuse since it opened in 2011. They have led to lock closures and unexpected renovations and damage repairs costing millions of Euros.
Parallel to the work at LWB, the Kaiserschleuse gate’s 80 ton undercarriage has been undergoing structural adjustments at a second German shipyard – Fassmer Werft. Officials said that work was to match unspecified changes being made to the gate itself.
The Kaiserschleuse was closed in April because of the gate work at LWB and Fassmer. Ships heading to the inner port were rerouted through the port’s second big lock – the Nordschleuse.
However the simultaneous breakdown of a rail swing bridge near the Nordschleuse meant that even those ships using the alternative access route could not sail on into the inner port because of the damaged bridge.
In what officials described as a “monumental feat of engineering”, part of the116m metal bridge was lowered onto the 95m pontoon BHV Innovation and removed. That opened the way again for ships – but a new rail bridge will be a long time coming.
To ease ship movement even further, the closed Kaiserschleuse was also reopened much earlier than planned after officials, in another deft hydraulic engineering job, swiftly installed a reserve lock gate.
