Why Does My Shower Water Smell Like Onions?

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Picture this: You're luxuriating in a hot shower, taking your sweet time, when suddenly a faint but unmistakable whiff of onions hits the air. Ick! If you're dealing with offensive bathroom odors, it's important to tackle the problem right away in case it's a health hazard.


Even if you haven't encountered a stinky shower, chances are that you will at some point, and it never hurts to be prepared. Luckily, most shower drain odor-related issues are easy to solve.

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Shower water odors typically occur because of a clogged drain, either from hair and dead skin cells or soap scum, or you may be facing a problem with your P-trap, which indicates a deeper clog.

Common Causes of Drain Odors

If your shower water smells bad, this is likely due to a clogged drain. Clogs can cause smells because they trap bacteria and don't allow the water to drain properly. Trapped hair and dead skin cells are a major cause of clogs, or you may be dealing with soap scum buildup. In both cases, your water might smell vaguely musty or otherwise unpleasant.


Otherwise, the problem may be related to your P-trap, which is a U-shaped pipe that stops sewer gases from entering the home. If your water smells like sulfur and/or there's standing water around your drain, the clog is probably in the P-trap.

How to Get Rid of Drain Odors

Are you ready to banish that pesky shower onion smell once and for all? Start by cleaning the area around your drain. A mold/mildew remover will do the trick. Then, to unclog your drain, use a bottle of drain cleaner to get rid of hair and other debris. If the odor disappears after a day or so, then you've successfully unclogged the drain.


Sometimes, though, you may need to physically move debris down the pipe to get it clean and smell-free again. A toilet plunger should work, but just in case, you'll want to have a good-quality drain snake on hand for hardcore clogs.

It's important to note that if you can't get rid of shower drain odors on your own, it's likely time to bring in the big guns. If there's an issue with your shower or septic tank, it's best to leave this to the pros.


How to Prevent Shower Clogs

Preventing shower clogs from happening in the first place will make things easier on you in the long run. Try brushing your hair before you shower or use a mesh drain (otherwise called a hair catcher) to catch hair and soap scum. It's also a good idea to flush your shower drain regularly to prevent clogs from forming. Simply boil a large pot of water and pour half of it down the drain. Wait five minutes and then pour in the rest. This will help loosen and dislodge soap, grease, and other debris before they become a problem.




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