Chasing Down a Simple Under Sink Plumbing Leak

A leak under a sink can be an annoying problem, your drain may be leaking waste water and creating a mess. This can happen for a variety of reasons, but with a little detective work, it is possible to discover the cause. We can not only find out where the leak is, but we may also determine how it occurred and reduce the chances of a recurrence. Dealing with garbage disposal units is beyond the scope of this article, and we will only be covering simple under sink leaks. A Bathroom or Kitchen Sink? There are a few differences in the way that a bathroom and kitchen sink works. A bathroom sink will have a “tail piece,” which is a straight pipe that drops from the bottom of the sink. This pipe will usually have a rod protruding on the back that is connected to the faucet with another pipe; this section is known as the “sink stopper assembly.” The “tail piece” also connects to an “S” shaped pipe which is known as a “P” trap after which the pipe goes into the floor and out into your drainage system. A kitchen sink, on the other hand, will not have a “sink stopper assembly” although it may have an attached hose above the dishwasher trap. You may also notice that a double kitchen sink will often have a pair of lines connected together, these will be above the trap and come in from both sides. Where is the Leak Located? Most times we find that the leak is located on a joint related to the waste water pipe. The drain has to move a lot of water on a daily basis, and a variety of changes could cause a leak. Let’s first take a look at the kind of pipes that are located under the sink. For those in more modern properties, the pipes will probably be ABS; these plastic pipes are usually white, but they could be black in some homes. Some people may have older chrome style pipes that are very easy to identify. It is important that any replacement parts match the ones that are currently installed. Some Quick Fixes: The source of the leak should be fairly easy to locate as there will be a pool of water under it. If in doubt, turn the faucet on to see where the water is coming from. The offending part will usually be a joint rather than a section of pipe. If you’re lucky, the leak may be the result of a pipe that has been bumped or jarred out of alignment. It may be possible with plastic fittings to simply push the pipe back into position. Just take a firm grip on the connecting pipe and push it into the related joint. It may be the case that a washer has failed or joint needs replacing, depending upon your experience this may be an easy fix for you. Once any repairs have been attempted, always test the system by draining an entire sink of water and have a suitable receptacle on hand just in case. Avoiding Future Problems: In many cases of a basically misaligned pipe, the problem could be caused by reaching under the sink for a cleaning product. It may be a better idea to limit the number of items under your sink or even store them somewhere else entirely. In bathrooms, many people store cleaning cloths or sponges over pipes, and this can cause problems. Any kind of interference with and/or unnecessary weight on pipes under the sinks in your home can lead to leaks and damaged pipes. By Giovanni Longo President Flood Brothers Plumbing Giovanni Longo is a 3rd generation master plumber who has been practicing his craft and trade in the greater Los Angeles area for well over a decade and a half. A plumbing and hydraulics-engineering innovator, Giovanni’s particular world-class expertise focuses on dealing with challenging sewer system designs as well as resolving complex commercial and residential draining issues. As a certified Flood Mitigation expert, he is also well versed in a wide variety of water damage and remediation solutions.