Electric can also spike in the summer with A/C.

Another was at a bar, and his drink got spiked with narcotics. 

Up until a couple of months ago, the water usage was typical, I think around 8,000 gallons but then it spiked to over 64,000 gallons. 

See if there is a spike then address the spike..

I live in a market where purchase prices were high even before the spike.

Apple, Google, Xerox, Fuji film, and Meta are all coming into the area. 5k people a month move to the area which has created a housing shortage, rent spikes, major appreciation (not just due to inflation) and you can still find single family homes for sale on the MLS in good condition for ~250k+ Tenant-landlord laws are landlord-friendly and taxes are low.

Unless there is another spike or access to easy money that we had back in the early-mid 2000's. 

The high-usage unit has a minimum of 75 gal/day with an average of about 400 g/day and more spikes over 1000 gals.

You should also be monitoring the bills from the water company to see if there are any spikes in usage. 

Maybe they will build a large low income housing complex near you in 5 years and crime spikes way up and the area goes to crap maybe they will build a prison nearby or there is a shooting on that street .