Water, gas, and to a great extent electrical systems do not work on oversubscription, ie their aggregate capacity meets or exceeds the needs of all their customers peak potential demand, at least from "normal" demand standpoint.
Hi, former municipal water and sewer commissioner here. We size the system to meet likely demand, but not peak demand. If it's a hot dry summer and everyone wants to water their lawn, or there's a big fire that's drawing a lot of water from hydrants, we can have capacity problems. We deal with it by interrupting service to a few large customers, a car wash and a golf course. But it's not really comparable to broadband service, because on the Internet, nearly every consumer end user device could easily saturate the entire network if it wanted to. It's like every house having a 100,000 gallon toilet. Better hope you don't have a lot of people flushing at once. R's, John