On my 40.07 fort, i embarked over an aquifer, but it was willingfully as i wanted to make use of it as an easy water source underground
I made a cave in to pierce the aquifer with a few 3x3 layers dropping into it.
I think it worked good, though as usual my miner making the final channel on the surface to drop the whole thing i prepared got unconscious from what i assume is some kind of shockwave, but he recovered quickly.
Here's the aquifer that is now pierced by the accumulated fews layers i dropped on it
Happy that everything went smoothly, i ordered a floor tile leading into the mass piercing the aquifer and ordered a stair down.
The floor was made but the stair wasn't , waiting for a while , still not dug down.
I looked at the list of message the fight reports and noticed the miner fighting, "slammed into obstacle, unconscious, get up", well that was the wind/shockwave of the cave in i guess.
Looking for the miner he was nowhere to be seen, and i then noticed a "horrified" dwarf message.
Zooming in i saw, the miner was drowned in the river
What? why is that miner went to jump in the water and drown for ?
It couldn't be the cave-in shock that threw him there (as seen the distance is too big) because i saw when he moved away after the cave in and his supposed short unconsciousness, so for reason i have no idea the guy must have jumped on his own.
Wouldn't be that bad if the miner was not still in possession of the unique pick of the whole fort.
And no dwarf is ever going to dig that stair without a pick.
No metal or stone available yet on the surface and diggable area, so no metalsmith forge and so no pick forging possible.
Caravans are probably a few months away, so no trading a pick (despite i made several wood craft in prevision)
So my solution was to build a screw pump to drain a bit of the river and get someone to fetch the dwarf corpse and throw it to my corpse stockpile while waiting for slab/coffin
Unfortunately my first attempt failed, i forgot to build some walled corridor to lead the water extracted away from the pump operator i just assigned to the job, so the guy ran away afraid of the water getting around him
The pick was still there, i needed to mount a better rescue operation, and additionally the poor bugger corpse so i could bury him
Migrants came but not a single guy with a pick, so i still had to follow my plan.
So i setup another pump , this time some walling enough to lead the water away a bit
Assigned a few more pump operator to the migrant so i could at least get 2 guys working at the same time, and the pump started
And ... it worked !
The water lowered enough (1/7 water around the corpse+items) apparently for the dwarves to carry what they had to carry (i had enabled the order to gather outside refuse too, just in case)
No more item in the river bottom, success !
Yes ! the pick was well rescued, along the poor guy corpse.
The mission was completed, i was proud of my dwarves.
Though there was a couple more ponds out there
And when all was well, the digging of the stair (that i changed to up/down one, as i noticed fortunately before the digging that i did a designation mistaked) ...
You must be kidding me, a 2 layer aquifer ?
Oh well looks like the game really hates me .