This came to mind because I recently had reason to set up automated sump pump monitoring for a rental property which doesn't have a proper basement, just a crawl space.
We had the choice of just installing a binary state (wet or not wet) zigbee liquid sensor, which we did, talking to a cheap USB dongle and home assistant, just above the height of the sump pump. But in addition to that I put a $60 camera which has a medium-wide overview of the whole crawl space, generally centered on the sump pit so that it can be checked in the event the liquid alarm goes off.
Stapled some cat5e across the floor joists that comes up through a small hole in the utility room where the PoE switch is. Theoretically it should also serve to check for things like "are raccoons inhabiting the crawl space?" or a few other possibilities.