The flange is the rim where the disposal meets the sink opening. If the seal there fails, water can appear at the top of the disposal and run down the housing. Leaks at the dishwasher inlet or drain outlet can wet the same cabinet, so the highest wet spot is useful evidence.
Observe without running the motor
Leave the disposal switched off. If you have already seen a leak, note whether it happened when the sink held water, while it drained, or when the dishwasher emptied. Keep clear of wet wiring and stop using the fixture if water is escaping.
Show the plumber where it starts
Take a picture of the sink opening and the visible fittings beneath it. Mention recent sink or disposal work. The plumber can check the flange seal, mounting hardware, and outlet connections before deciding which component to service.
Learn more about our home plumbing service.