Oct 08, 2018 · This is the telltale sign of a kitchen sink drain pipe leak: whatever is underneath the sink is soaking wet. If there’s nothing under the sink, you’re more likely to see water pooling on the bottom of the cabinet or the floor. If the leak has been there for a while, though, you could see water stains under the sink. Do you have a Garbage Disposal Leak? by A&T HVAC | Dec 28, 2020 | HVAC, Plumbing. If you’ve discovered your garbage disposal is leaking, don’t despair. Usually, it just involves a simple fix. If you’re unsure if you have a garbage disposal leak, be proactive by checking key areas to minimize damage. Disposals usually leak from one of three... May 19, 2005 · Hi, The leak is from the bottom part of sink strainer that goes into a compression coupling on the "drain pipe," after a closer examination. This (compression coupling) is very tight as it can't be hand twisted any further.