This one needs a licensed pro
Likely cause: a leak at the garbage disposal
Water is leaking at the disposal, its sink flange or its connections. Fixing it means taking the disposal down, so call a plumber.
Why this happens
Bob Vila says a disposal leak usually shows at one of three places: the top where the disposal meets the sink drain, a side where the dishwasher hose or the main drain pipe connects, or the bottom. At the top, the sink flange is sealed with plumber's putty and held with bolts under the sink, and if the putty breaks down or the bolts loosen the seal fails. InSinkErator points a leak at the top of the disposal to its mounting assembly, and says that for a leak at the bottom or the container body you should first confirm it is not dripping down from higher up, while a motor joint leak is one to contact the maker about. Moen says a damaged drain elbow gasket can let water run down between the shell and the unit and out of the bottom plate.
What to do right now
- Turn off the disposal's power at the breaker box first, but only if you can reach the panel safely. If you cannot, do not add water, stay away from the area and call an electrician or emergency services. Bob Vila says to unplug the disposal at the outlet and turn off its power at the breaker box before you check it for leaks. Unplug it only if the plug, cord and outlet are dry. Keep it off until a plumber has looked at it.
- If you see water on the disposal's plug, cord or outlet, leave them alone and call an electrician as well as a plumber. About sewage that has reached outlets, appliances or wiring, This Old House says to shut off power to the affected circuit only if it can be done safely, and to contact an electrician or emergency services if you cannot safely reach the breaker panel.
- Do not reach into the disposal. Waste King says never to place your hand inside the disposal. Taking the unit down to reseal the flange or replace a gasket is plumber's work.
- To help the plumber, and only if no plug, cord or outlet under the sink is wet, run Moen's leak test with the power still off. Put the stopper in and fill the bowl. Wrap paper towels around the sink flange at the top, around the drain elbow on the side, and around the dishwasher connector. Release the stopper, let the water drain, and see which towel is wet.
- Bob Vila notes that top leaks show most while the sink is plugged, and side and bottom leaks show most while it drains. Note which one you see.
- Dry the cabinet floor only with the breaker off and away from any wet plug, cord or outlet, and keep a bucket under the disposal until the repair is done. Skip the dishwasher too, since Bob Vila says the dishwasher hose drains into the disposal, and use this sink as little as you can until the plumber has fixed it.
When to stop. If water reaches the disposal's plug, cord or outlet, do not touch it and call an electrician. Turn off the breaker only if you can reach the panel safely. Do not run the disposal until a plumber has fixed the leak.
What to tell the plumber
- Which paper towel was wet: the top flange, the drain elbow, the dishwasher connector or the bottom.
- Whether the drip shows while the sink is full and plugged or while it drains.
- The disposal brand and model, and how old the disposal is, if you know.
- Whether the sink is a double sink and which bowl the disposal is under.
- Whether a chemical drain cleaner has gone down this sink.
Build the full list: what to tell the plumber.
Start this troubleshooter over
FourHome is our sister brand. Browse all FourHome replacement faucet and shower parts on the FourHome Amazon store. We earn from purchases made through this link.