Flooding would be catastrophic even today, but it is not uncommon for rainwater and groundwater to fill spaces over time. Most abandoned US missile solos are filled because of rain and it is not uncommon for old, abandoned bunkers to be filled too. If we’re comparing it to an “ancient” structure it can add up.
The LHC currently uses sump pumps to deal with natural water infiltration. Without those pumps the water can collect in the space. There are also installed sources of water that could leak over time, such as for firefighting.
Flooding would be catastrophic even today, but it is not uncommon for rainwater and groundwater to fill spaces over time. Most abandoned US missile solos are filled because of rain and it is not uncommon for old, abandoned bunkers to be filled too. If we’re comparing it to an “ancient” structure it can add up.
The LHC currently uses sump pumps to deal with natural water infiltration. Without those pumps the water can collect in the space. There are also installed sources of water that could leak over time, such as for firefighting.