The Fehmarnbelt project has now placed its second tunnel element on the seabed. It happened on June 27, 51 days after the first element was reported in place off Rødbyhavn.
That moves the project into a phase in which progress can begin to be measured in practice. After several years of delays, disputes and preparations, there are now two concrete dates in the part of the work that will carry the entire future timetable.
The gap between the first two elements therefore matters. Fifty-one days is the first real measure of pace in the lowering operation, and it shows how sensitive the timetable is. The Fehmarnbelt tunnel consists of 89 elements. Two are now in place. That leaves 87. If the gap between the first and second element were repeated throughout the remaining lowering work, the rest of the elements would take 4,437 days to put in place. That is a little more than 12 years.
That calculation is back-of-the-envelope arithmetic and should be treated as such. The first two elements are far too narrow a basis for a real forecast for the rest of the tunnel. The first lowering operations are taking place in a start-up phase, and currents close to the coast have been the main challenge. The calculation still shows why the rhythm between the elements now becomes critical. Every extra week between two lowering operations quickly carries through in a project where 89 elements have to be placed one by one in an 18-kilometre tunnel trench.
12 days between each lowering
The original master schedule provides the benchmark. It allowed 36 months for the lowering of the tunnel elements. That corresponds to about 2.5 elements a month, or roughly one element every 12 days on average. The gap between the first two elements is far from that rhythm.
That is why the next element becomes important. The first element was the breakthrough after a long period without any lowering operations. The second showed that the operation could be repeated. The third will be the first indicator of whether the work can begin to settle into a more stable pace.
If it comes quickly, the 51 days between the first and second element will look more like a start-up phase shaped by weather windows and difficult currents close to the coast. If several weeks pass again, the pace becomes a much bigger problem for the forthcoming timetable. That development will be increasingly difficult for the client, the contractor and the political level to avoid.
The lowering operation also runs directly into the project’s financial dispute. The main contractor, Femern Link Contractors, has already put both money and months on its assessment of the delay. In its DKr14.5bn claim against Femern A/S, the contractor estimates that the delay to the work amounts to 20 months. The claim is linked to the marine works and to the strict environmental requirements imposed on the project by the German authorities. Those requirements were not known when the contract was signed.
Revised timetable
The central point in this context is the time estimate. FLC has put 20 months on the delay it believes has hit the lowering works. Reality is now starting to provide the first figures against which that assessment can be measured.
At the same time, the first lowering operations are taking place in the coastal beginning of the tunnel trench off Lolland. This is where the currents have caused problems, and this is where the project now has to show that the practical difficulties can be turned into a repeatable working rhythm. Farther out in the Fehmarnbelt, other constraints await, including German environmental requirements and work inside the Natura 2000 area. For now, the coastal section is the concrete test.
The Fehmarnbelt project has said that a revised timetable will be presented once four standard elements and one special element have been lowered. That means the next elements are more than ordinary progress on a construction site. They will form the data on which the plan replacing the 2029 target must be built, and show how far the delay really extends.
The second element on the seabed is therefore both progress and warning. The Fehmarnbelt project has entered the phase that stood still for far too long. At the same time, the 51 days between the first and second element show how large the gap is between the first lowering operations and the pace required for a completed tunnel.
The real test begins now. The Fehmarnbelt project has shown that a tunnel element can be lowered. It has also shown that the operation can be repeated. The next lowering operations must show whether the work can find the rhythm on which a new timetable can be built.
