Drip.
There's a sound that comes before a rockslide. Once you've heard it once, you'll never forget it. It's a small sound, and builds up into the crescendo of the landslide. It starts with the little sounds of pebbles rattling.
Drip.
It doesn't come that way with all things. Artificial objects are usually built without this handy feature inside. They rely on alarms, on bells and whistles to alert the user of danger.
Drip.
In this case, however, the sound was that of a single drop of water, falling.
Drip.
"ALL CREW TO THE EMERGENCY RELEASE VALVE, IN THE PROGENITOR'S NAME!" bellowed the construct. Unicorns were running frantically over the wall, but at the sound of the bellowed order, they organised themselves and quickmarched over to the cave. Their picks were ready, and they commenced the release. The construct was horrified. The Progenitor Himself had given him a task, and he would have to fail it. The water was at the level of the dam, and the pressure was building. Even the tiniest bit more pressure would destroy the dam and undo all the work. The only chance would be to leak out some of the water. This had been done before, and worked...the construct had only not predicted they would need to do it again so suddenly. He looked desperately out at the wall, at the dripping from there, and prayed that the Progenitor would speed their work.