This is an existing tool, and it's one that the occupants were warned would be used if they continued their violations.

Criminal charges are slower, and don't do as much to stop the immediate threat without custodial arrest and pretrial confinement, either in jail, which itself is a public health issue, especially when high-risk transmission behavir is involved, or in separate isolation (which IIRC is available for public health order violations but is manpower intensive.)

I also see that as a vastly worse legal precedent than shutting off your water to deter disease-spreading large gatherings. That's a great way to make sure we can throw lots and lots of poor people in jail -- just as soon as the pandemic is over the our jails aren't overwhelmed as a matter of course.