Irrigation wells in my area of Nebraska are usually 500 gpm to 1000
gpm. Most are probably in the 700 to 800 gpm range. Wells have to
have flow meters.
Natural Resources Districts in Nebraska are responsible for
enforcing the laws regarding irrigation. I've never heard of anyone
being ordered to stop irrigating.
Farmers have been fined for irrigating roads but that goes through
county court. Sheriffs write tickets for that kind of thing.