Visible low-flow indicators can reveal small ongoing use, but register designs vary. Read the district's meter guidance rather than forcing covers or fittings.
IWVWD describes meter checks as part of investigating high use, and EPA also recommends comparing readings during a no-use interval. Automatic irrigation, toilets, coolers, softeners, ice makers, and water-heater filling can invalidate an apparent result.
Keep this boundary: Do not operate the street-side district valve. A moving meter proves registered use during that interval, not a specific broken pipe.