Comment by fuoqi
6 hours ago
I wonder how much would it cost to build a tunnel as an alternative to the Panama canal to fundamentally resolve the drought issues. 1.8 km is comparable to ~80 km (probably a shorter tunnel will suffice) and dimensions are also similar (at least for the old Panamax).
Looks like the Norway tunnel is through hard gneiss. That rock formed 100s of millions or a billion years ago. https://en.wikipedia.org/wiki/Sveconorwegian_orogeny Norwegians know how to tunnel through it, like https://en.wikipedia.org/wiki/B%C3%B8mlafjord_Tunnel and https://trid.trb.org/view/512421 .
The Panama Canal famously had to deal with a lot of mud, clay, and unstable rock, causing many landslides during and after construction.
The geology of Panama is quite complex and the isthmus is only 4 million or so years old. "The geology of Panama includes the complex tectonic interplay between the Pacific, Cocos and Nazca plates, the Caribbean Plate and the Panama Microplate" - https://en.wikipedia.org/wiki/Geology_of_Panama
Looks like Panama City is working on a monorail tunnel to go under the Panama Canal for Line 3. https://www.herrenknecht.com/en/references/referencesdetail/... mentions the complex geology for the TBM has "Heterogeneous ground; La Boca Formation: Sandstone, siltstone, tuff, mudstone, pyroclastic rocks; Tucue Formation: Basalts and andesits; Panama Formation: Tuff, sandstone, agglomerate".
That's quite of bit of soft and crumbly rock.