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How to Prevent Water Behind Kitchen Sink

How to Prevent Water Behind Kitchen Sink

Water is a humble and valuable resource that needs to be treated with respect and care. Some may say we waste more water than any other resource on Earth. That’s why it’s important to learn how to prevent water behind kitchen sink. When it comes to the plumbing of your kitchen, you can reduce the amount of wasted water and also improve the efficiency of your sinks, washing machine, and dishwasher.

Water behind kitchen sink is not only annoying, it can be a threat to your household as well as you’re plumbing. Water that backs up behind kitchen sink can cause your utility bills to rise, break your walls and floors, and destroy the rest of the items in your house.

Usually, water behind your sink is caused by clogged drains

The most common cause of water collecting behind the sink is clogged drains. The problem usually lies in a clogged pipe. In most cases, it’s caused by a blockage that, once removed, gets rid of the problem. If your sink is leaking from the drain, you may be able to fix it simply by tightening the nut under the sink.

If your kitchen sink has two basins with a divider between them, water may collect on one side because of a leak in the divider. This can happen when you are using one side and water runs over the top of the divider into the other side. Or perhaps you have an undermount double-basin kitchen sink where water leaks down between the basins and collects on your countertop or cabinet floor.

Close the Drain Plug

Remove all items from under the sink and turn off the water supply to the sink. Open the faucet to relieve pressure in the system. Place a bucket under the drain trap to catch any residual water, then loosen the slip nuts connecting the trap to the drain tailpiece and waste line with adjustable pliers or channel lock pliers. Allow all of the water to drain into the bucket. Place some plastic wrap, a plastic bag or a small piece of carpeting over your drain opening so that no tools fall down there during your repair session, as this could result in more problems for you later on.

Loosen and remove the slip nut holding your drain trap to the waste line using hand pressure or channel lock pliers. Remove the end of your waist line from inside your wall with your hands; if it’s tight, wrap a rag around it and twist it gently with channel lock pliers until it comes out.

Remove the Garbage Disposal Plug

Remove the garbage disposal plug. This is one of the first things to check if you notice water leaking from under your sink. The plug, which is located underneath the garbage disposal may have been knocked loose during installation of the garbage disposal, or it may have fallen out over time. Remove the disposal, and check underneath it for rubber plugs that fits into a hole on top of the mounting ring. If it’s not there, you’ll need to retrieve it from inside your garbage disposal, or replace it with a new one.

Run the Water

Running water into the disposal for 30 seconds before turning it on helps flush out any food particles that may be stuck in the unit. It’s also a good idea to run the water for a few seconds after you turn it off, to ensure no food particles are left. Run the Garbage Disposal Regularly

Check the P-Trap

Check the P-Trap. This is the most common cause of water leaking behind your cabinet. If you need to access the P-trap, remove the sink stopper and clean away any debris. If you see water leaking from the joint where the trap connects to the sink’s drain, unscrew and clean it with a pipe cleaner. Reattach the trap by hand and then tighten it with adjustable pliers. Don’t over-tighten it: If it’s too tight, it might leak later.

Check for Leaks in Other Fixtures. Water behind your kitchen sink may have originated from some other source, such as a leaking supply valve or a faulty dishwasher line. Open up all cabinet doors underneath your kitchen sink and inspect for leaks at other fixtures. Check for Cracks or Leaks in Supply Lines. Turn off your home’s main water supply to prevent damage from a burst pipe while you’re at work fixing things under your sink.

Replace the P-Trap

The P-trap is the curved section of drainpipe located under the sink. This curved portion is what allows water to flow down and out of the sink. When the P-trap is clogged or broken, it can allow water to begin seeping out of the bottom of the sink. Replacing a P-trap is an easy do-it-yourself job that requires only a few tools to complete. Steps to Prevent Water Behind Kitchen Sink:

  1. Turn off water supply at shutoff valve under sink.
  2. Place a bucket underneath pipes to catch any excess water still left in pipes.
  3. Remove old P-trap with adjustable wrench.
  4. Screw on new P-trap onto bottom of tailpiece and onto waste arm coming from wall. Tighten with wrench until hand tight, then tighten one more turn with wrench to ensure tightness.


Leaky dishwashers, malfunctioning garbage disposals, broken sink stoppers, and burst pipes are all common emergencies in the kitchen. It’s critical to fix the leak quickly before it causes any permanent damage. To avoid water behind the sink and other disasters, be sure to familiarize yourself with your equipment and areas of potential weakness.

The best way to do that is to read your owner’s manual from cover to cover and be prepared when disaster strikes. The only way to stop water seepage behind the sink is to remove the lead pipe, which may mean removing all the tiles around the sink to get at it.