My fortress is built under an ocean, so I decided to build a mechanism that takes advantage of the ocean's hydrostatic pressure to flood my entire (very long) entrance hall in a single frame.
Another feature of my entrance hall is a box built into the ceiling with a pet on a rope overlooking the hall, used to watch for ambushers. Floor grates seperate the box from the hall itself, and the only way into the box is from deep within my fortress, so the pet is completely-safe from attackers.
Anyways, after getting all of the required floodgates, safety hatches and drain covers set up and linked, I opened the floodgate blocking the passage which was to conduct water from the ocean to my entrance hall and ordered a recent immigrant with no friends to carve a fortification into the side of the ocean basin. I didn't want to lose anyone important, you see.
As expected, there was a long stall as the my computer processed hundreds of units of water rushing from the ocean into my fort in a single frame.
Immediately afterwards, several facts were brought to my attention:
- Pressurised water can and will flow upwards through gaps in the floor.
- Floor grates, to wit those seperating my observation post from the entrance hall below, do not stop this from happening.
- I had neglected to install any doors or other physical obstructions into the tunnel running between said observation post and the rest of my fortress.
- My entire fortress save for the farms and dining hall was now completely-full of seawater.
However, most of my fortress, including my miners, had been safely behind the dining room's doors when the deluge hit; I decided that savescumming was for the weak and that I would try to make the best of it.
Then I realised that all of my food supplies, including seeds, were still in their stockpiles along with many gallons of pressurised seawater.
Then I savescummed.