Why Your Tap Water Is Cloudy (and Why It Matters)

Picture your ideal glass of water. Maybe there's ice in it, or possibly a slice of lemon or lime, but regardless of the variations, it's probably safe to say that the water in that glass is clear—not cloudy. While cloudy tap water usually clears up on its own—and, as a result, is rarely cause for concern—it may be a symptom of a larger issue with your plumbing. Or it simply could have to do with where your household's water is coming from.

Why is my tap water cloudy?

To figure out what, exactly, is making your tap water cloudy, start by determining whether this is only an issue with water from one faucet in particular, or all the ones in your home.

Cloudy water from a single tap

Cloudy water limited to a single tap in your home is likely tied to the aerator on the faucet, says Roy Barnes, a plumber with roughly 30 years of experience, and the co-owner of Service Force Plumbing in Rockville, Maryland. To find out, remove the aerator from the tip of the faucet (most screw on/off, but others require a small key), and put it in a glass of white vinegar for about five minutes to remove mineral deposits or other contamination. You can tackle any stubborn spots with an old toothbrush. When the aerator is clean, give it a rinse, and pop it back on the faucet. Then turn on the tap. If the water coming out of it is no longer cloudy, you've found the culprit.

Cloudy water from multiple taps

When cloudy water is coming out of more than one tap in your home, Mark Collins, a fifth-generation plumber, and the CEO of 1-800-Plumber + Air, recommends filling a clear glass with water, then letting it settle.

If the water clears up

If the water clears up quickly, you'll know that cloudiness was actually tiny air bubbles. These bubbles rise to the top of the glass, then enter the air—leaving the water in the glass crystal clear.

So, how did the bubbles get there? There's probably residual air in your water line, says Collins. This can happen for multiple reasons—including cold outdoor temperatures. According to Barnes, cold water can hold more oxygen than warm water, and may look cloudy for a few seconds because of that extra air. Another more concerning explanation. he says, is that your water pressure could be too high.

Your home has a pressure reducing valve (PRV) that reduces the higher-pressure water from your supplier to a safe pressure for your home plumbing. If the pressure is high enough to make your tap water cloudy, Barnes says it could be causing other issues in your home, like shortening the life of appliances designed to function at lower pressures. This is something that anyone apart from the most competent DIYers should call a licensed plumber about, Barnes says—both to test the water pressure, and replace the PRV if needed. 

If the water doesn't clear up

According to Barnes, the two most common explanations for tap water that doesn't clear up when left to settle, are hard water containing a lot of dissolved particles, and a hot water heater that needs to be flushed.

If it's only your warm or hot tap water that's cloudy, there's a good chance that sediment has built up at the bottom of your hot water heater, and needs to be emptied, or flushed. This is something you should be doing yearly, Barnes says, in order to prevent high utility bills and reduce wear and tear inside the water heater.

If hard water is the problem, Barnes recommends having a professional plumber or filtration company test your water, then install the appropriate softener and/or filter. 

When is cloudy tap water cause for concern?

If the cloudiness has a brown tint, starts to look milky, or doesn't clear up after flushing the hot water heater or having your water tested, Barnes and Collins both recommend having it evaluated by a professional to make sure that it's safe.