Looks like a Paramount side flow IFCS (in floor cleaning system)? Seems you can replace the top dome cap as the easiest fix. Thankfully there are many sites to find your part: Link to Infloorpoolparts.com
The housing is stronger CPVC, while the domes deteriorate over a decade or so-replaced my entire valve assembly (top flow) last year for leaks & fear of failure.
I’m sure a clever electrician can wire up a redundant flood protection system—I have the secondary condensate Safe-T-Switch’s on all my AC units for flood reasons, so a similar system could be designed. Patents anyone???
I have one of these systems and I’m going to be looking for electronic pressure gauges that will send an alert through Smartthings if there is a pressure drop while the pump is on. I had my lid leak around the seal and it was a little scary.
Another reason why I don’t run my equipment at night ... a lot of bad things can happen that you’ll sleep right through (especially because my equipment is located a fair distance from my house). At $8-$10 per CCF of water on average, even a minor leak can cost you a lot of money....