Are you arguing that losing electricity is a bigger problem than running out of water?
>> creating a new attack vector against critical infrastructure
Just because you've never thought of it before, doesn't mean it's new. It's long been assumed that foreign agents have access to critical infrastructure systems in the US. Who cares about a hacker emptying a water tower when some have the ability to cripple power grids and overload power plants? Although I do get a chuckle out of thinking about a hacker being malicious by watering peoples yards.
So... information leakage may lead to literal water leakage.