[MS90]

It also has a disadvantage in that it's extremely porous and allows water to seep through it, which expands and contracts with temperature changes and causes the limestone to crack. There's areas around town where roads have been cut through hills, and if you drive through these after a big rainfall you can literally see water pouring out the side of the rock face. Chunks of limestone breaking off and falling onto the side of the road is a pretty regular occurrence.

There's other issues, too, such as the lake that runs through the middle of the city, the underground rivers and cave networks in the area, and the unstable clay on the East side of town that expands and contracts with rain, causing all sorts of problems.

[bin_bash]

Do you actually have any sources or are you just making assumptions based on how you see limestone behave on the surface?

I don’t have sources myself but to me the porous nature of limestone seems like a benefit since water would easily flow to the water table instead of flooding in the tunnel.

Erosion seems like it would be a far bigger problem for tunnels in soil or sand than it would be for limestone.

[bobthepanda]

Water generally flows down. If you have a high water table building basements is usually foolish.

Limestone, because it dissolves in contact with acidic water (and rainwater is slightly acidic) is also prone to sinkholes. Best to keep the ground stable by not exposing it to more water. It happens so often in Florida there’s an FAQ page. https://floridadep.gov/fgs/sinkholes