Water pump that can shut down if no water from supplier
The HC6000 can turn on an outlet at a certain water level and turn off the outlet at a certain water level.  Attach an AC pump and this is an example of a pump that can turn off when the water level is too low.

https://www.amazon.com/HC6000-Hi-Lo-Controller-Float-Switch/dp/B006AU4L4U/ref=sr_1_1?keywords=hc6000&amp;qid=1554961547&amp;s=gateway&amp;sr=8-1