By the look for things you can tell this isn’t normal or maybe even suppose to happen. But guess again this happens each and everyday. It’s a nightmare if your plumbing isn’t updated or if you don’t have the proper shut off’s.
This issue could have been solved easily if they had a shut off that worked but instead they had to call the city at night for an emergency to shut the water off. It’s never fun to have a shower coming into your house other then through your bathtub shower head. The force of that water coming through the pipe was stronger then what comes through your shower head.
be careful and be on top of as much plumbing as you can in your home. Some things you can’t help but old neglected drains and pipes is something you should consider addressing before it’s too late.