This makes me think about mechanisms to protect water pipes in much the same way as GFCI protects electrical wiring. Of course, measuring return flow back into the sewer would be hard to do. But maybe a flow meter in the main that has a threshold where the flow rate has to fall below that level at least every N hours (such as 3 hours), and shuts everything off if the flow stays high too long, might work to avoid those extensive levels of damage from long term water flow. But this would be for a plumbers forum. It was just a thought.
