[sokoloff]

There are motorized whole house water valve shut offs that can be connected to leak sensors. Have a water heater rust out, leak, fill the pan, trip the sensor, shutoff the house water, continue to slowly leak its 30-60 gallons out, but at least it’s not continuous, pressurized leaking until you notice.

Even without an automated valve, you could shut off a manual valve yourself if alerted to a slow leak.

Leak sensors can also help if you have a failed sump pump. My sump pits have a main pump, about 6” higher a second battery-backed pump with a (local) alarm. It’s a good idea, but the battery pump often fails to run when needed because of sitting so long, so the alarm is a wise addition. (If it ever goes off while you’re not testing the system, something needs attention.)