https://www.newcivilengineer.com/latest/fehmarnbelt-delayed-...

> Sund & Bælt, the Danish transport company overseeing the project, has now confirmed that IVY has not yet completed full testing and has not received final approvals from relevant authorities, despite arriving on site last October. The preparatory delay is about 18 months, a setback that project managers say makes meeting the original 2029 opening target difficult.

> There is also an issue with restrictions around the working conditions. Contracts for the main construction works were signed in 2016, before German planning approval had been granted. That timing meant certain later-imposed requirements – notably restrictions on underwater noise from work vessels and limits on sediment spill in German waters – were not written into the original contracts, complicating attempts to speed up work now that the rules are in place.

Over budget, decades behind schedule because Germany does everything to rise costs and delay. First they sunk the bridge project, now they delay the tunnel project. See the Wikipedia page.

Hadn’t they designed a bridge, they were getting ready to build it, and it was changed to a tunnel.

It does make sense since tunnels won’t need to closed for high winds like bridges do.

I might have misremembered bits of this.