Hate replying to myself, but I think it might be worthwhile to add: I have seen the internal workings of the water control systems of my fairly modest local area (3,000,000 area, largest municipal serves ~200-300 K). I would hate to see what happened if any of those controls were maliciously compromised, as it could lead to problematic flooding or draining municipal systems. I am concerned that the major controls for these systems are maintained computationally, but the tradeoff has been reduction in monitoring, and there may not be enough people on staff to mechanically secure the system if something seriously goes wrong. ~Fear mongering late on a Monday night.