A steady overnight change during a genuine no-use period supports further leak investigation.
IWVWD tells customers with a disputed high read to contact customer service and also check irrigation, overnight meter readings, swamp-cooler pumps, and running toilets. Work from those large categories toward a repair call.
Keep this boundary: A bill total cannot locate a leak or assign utility responsibility. Rate and usage questions belong with the district; private-plumbing evidence belongs in a service scope.