But NYC has a rather high level of vulnerability with a small number of choke points (there are currently only two water tunnels for the entire NYC metro area), but yes, the water infrastructure for a lot of major cities could be disrupted disturbingly easily.
> there are currently only two water tunnels for the entire NYC metro area
How are you counting this? If you mean Hudson River crossings between NJ and Manhattan, there are five: two road tunnel groups (Holland and Lincoln) and three rail grops (Upper/Lower Hudson and North River). When Gateway is complete (2030s), there will be four rail groups.
But if you mean the entire NYC metro area, there are significantly more: Manhattan <-> Brooklyn alone has the Hugh L. Carey for road traffic, and then six active subway tunnel groups. Manhattan <-> Queens has a similar number.
Thanks, I misread that. Although technically there are three operational water tunnels for NYC :-) — tunnel #3 is operational despite being under construction.
