Wasn't me, but when we had the excavator tear our house down and haul it away after the fire I saw water start spraying. I thought he hit the line the way the water was squirting. Suddenly it quit.
I asked them what happened. He said that something caught the valve and turned it on. I asked him why did it stop? He said he took the bucket and turned the valve back off.
This was a plastic line sticking out of the ground with one of the plastic valves on it. I was impressed.
Me, I'm just happy if I can get a full bucket of material and either didn't spin the tires or bog the engine.