One Side of Kitchen Sink Not Draining: Causes & Fixes

That familiar problem hits hard when dirty water refuses to go down one side of your kitchen sink. Standing water in the sink basin can quickly turn your kitchen duties into a frustrating ordeal. Food preparation becomes challenging, and washing dishes feels like an endless battle against rising water levels.

Here’s some good news – most single-sided sink drainage problems can be fixed without calling a plumber. A few basic tools and proper knowledge can get your sink back to perfect working order fast. Let’s check what might be causing the problem and go through some proven solutions that help countless homeowners restore proper drainage.

One Side of Kitchen Sink Not Draining: Common Causes

Understanding what’s blocking your sink helps you fix it properly. Several issues could be causing your sink’s drainage problems, from simple blockages to bigger plumbing concerns.

1. Food Debris Accumulation

Food particles, especially sticky substances like rice, pasta, and coffee grounds, build up in your drain pipes. These bits of food can form a thick paste that sticks to pipe walls, slowly narrowing the drainage path until water flow slows to a crawl or stops completely.

2. Grease and Oil Buildup

Hot grease flows freely down your drain, but once it cools, it solidifies and sticks to pipe walls. This sticky coating catches other debris passing through, making the clog bigger. This happens more often during winter when cold pipes make grease solidify faster.

3. Faulty Garbage Disposal

A broken garbage disposal on one side of your sink can stop water from draining. The disposal might be stuck, blocking water from flowing through properly. Sometimes the issue isn’t the disposal itself but how it connects to the drain system.

4. Blocked P-Trap

The P-trap, that curved pipe section under your sink, often collects various debris. Since this part holds some water to block sewer gases, it also tends to collect heavy materials that sink to the bottom of the curve.

5. Cross-Connection Problems

Double-sink setups share a common drain line. The connection between the two sides can become problematic, especially if it wasn’t installed correctly. This can make one side drain slower than the other or stop draining altogether.

Kitchen Sink Not Draining on one side

One Side of Kitchen Sink Not Draining: How to Fix

Now that we’ve identified possible causes, let’s get that sink draining again. These solutions start simple and move to more detailed methods.

1. Plunge the Affected Side

Put a stopper or wet rag in the other sink drain. Fill the problematic side with enough water to cover the plunger’s head. Place the plunger over the drain and push up and down strongly for about 30 seconds. This creates suction that can break up many clogs.

2. Clean the Garbage Disposal

Switch off the power to the disposal at the circuit breaker. Look for visible blockages in the disposal with a flashlight. Put an Allen wrench into the hole at the bottom of the disposal and turn it back and forth to free any jams. Once cleared, turn the power back on and run cold water while running the disposal to flush it out.

3. Snake the Drain

Put a plumber’s snake or drain auger into the affected drain. Turn the handle clockwise as you push it deeper into the pipe. Once you feel resistance, you’ve probably found the clog. Keep turning the snake to break up the blockage. Pull the snake out and flush with hot water to remove any leftover debris.

4. Clear the P-Trap

Put a bucket under the P-trap to catch water. Use channel-lock pliers to loosen the slip nuts at both ends of the P-trap. Take off the trap and clean it well with a bottle brush. Look for damage during cleaning. Put the P-trap back, making sure all connections are secure but not too tight.

5. Use Natural Drain Cleaners

Pour 1/2 cup of baking soda down the drain, followed by 1/2 cup of white vinegar. Cover the drain right away with a plug or rag. Wait 15 minutes, then flush with very hot water. This natural solution can break down grease and organic matter safely.

6. Check the Branch Drain Line

Should previous steps fail to work, the problem might be in the branch drain line connecting both sinks. Use a longer snake to reach farther into the plumbing system. Put it through the affected drain until you meet resistance, then clear the clog as described earlier.

If these solutions don’t restore proper drainage, call a licensed plumber. They have special tools and knowledge to handle serious plumbing issues that might be causing your sink’s drainage problems.

Final Thoughts

A partially draining double sink shouldn’t disrupt your kitchen activities. Most drainage issues come from common problems you can fix yourself with basic tools and some effort. Running hot water down both drains daily and watching what goes down your sink prevents many of these issues.

Quick action on sink drainage problems helps avoid bigger plumbing issues later. Start with the easiest solutions, then try more detailed fixes if needed. Your sink should work normally soon.

FAQs

Can a double sink share the same P-trap?

Yes, double sinks often share a single P-trap through a special Y-fitting that connects both drains. This setup works well if installed correctly.

Why does my sink gurgle when the other side drains?

Gurgling shows a venting issue in your plumbing system. Air might have trouble entering the system as water drains, causing the noise and possibly slow drainage.

Should I use chemical drain cleaners on my kitchen sink?

Chemical drain cleaners might harm pipes and garbage disposals with regular use. They’re especially tough on older plumbing systems. Try natural solutions or mechanical methods first.

How often should I clean my kitchen sink drains?

Clean your drains monthly with baking soda and vinegar to stop major clogs. Run hot water down both drains daily after use to prevent buildup.

Can a clogged dishwasher affect sink drainage?

Yes, many dishwashers connect to the same drain line as the kitchen sink. A clogged dishwasher drain hose can stop your sink from draining properly, especially on one side.