I made a dark pact with the elder ones that dwell in the dark places of the world to commission my aquatic pen for my tame eels and dark engineering sciences. They have consumed the life of one of my fortress babies, snatched from the arms of their miner mother who toiled to complete the task stone by stone by the rising waters.
Yet i have been deceived for the price of success, a eel sits chained to a dark pool, stained with the lifeless corpse of a infant bobbing there, a less than spectacular success. All of this happened due to freak flooding via a sudden unmonitored surge of water, displacing the water level, which has trapped one of my own pump operators until it subsides. A flaw in my plans means the eel is not retrievable as pressure has pushed it to a undesirable place (my design is meticulously specific), the child is of secondary concern because eels and large aquatic livestock (soon to come) cost major cash and precious time to replace.
The eel entangled in the grate slathers wistfully at the child, dwarven lamb veal denied, it slumps to the bottom of the pool, barely alive after the ordeal of being put there, waiting for its kin to join it and foolish beef steak handlers to trip and stumble assuming the small lake of badly managed water that is gathering and steadily rushing at them doesn't claim them first.