In a chapter of 2013 master thesis, I have demonstrated that the U-Boat Bunker of Saint-Nazaire didn’t have any interest for the French Navy (Marine Nationale) as it’s concrete-structure would not endure a nuclear attack. It’s of course not the only reason why the Marine didn’t use the base after war. Here follow the others reasons. She also wanted to concentrate it’s submarine activities in the Brest and Lorient harbors’. The so many bunkers and submarine pens’ that inherited the Marine Nationale seemed to her useless at this moment. Also, St-Nazaire has never been a French military port in the History. The port was already considered as too small for the large military ships [Note 2: see the French version].
This year I also discovered in the Archives some others documents from the 60’s on an amazing subject: do the U-Boat bunkers can handle a nuclear explosion? Regarding the Bordeaux U-Boat bunker, I didn’t (still) found any study on that subject. This could be understood as the submarines pens of Bordeaux are – like the others – opened to the tidal basins. But the Bordeaux annexe tower, which is generally the only hermetic element of the whole structure, has never been finished. This could explain why there was no study conducted by the Army concerning the Bordeaux U-Boat bunker resistance to a nuclear attack. If case or such a nuclear explosion occurred, the blast would destroy the pens and the unfinished annexe tower would not protect us if we thought to seek refuge inside. Besides, and this final point concerns all the U-Boat bunkers, the radiations would not allow us to drink water even if a well was dug.
“All in all we are hardly no more advanced” as the Captain says to Tintin on a well-known vignette extracted from The seven crystal balls which can be seen on the second tidal basin of Saint-Nazaire.
Have a good V-E day!