Occasionally, trapped (or entrained) air will be noticeable in tap water. This is due to air dissolved into the water at its source, which can turn into bubbles after the water leaves your tap. These bubbles may make your water temporarily appear cloudy. Both the bubbles and cloudiness are harmless and will disappear when allowed to sit, similar to how the bubbles in soda will dissipate over time.You can confirm that the cloudiness of your water is caused by air in the water line by performing a simple experiment. Fill a clean glass with cold tap water and let it sit on the counter. Watch the cloudiness clear as the bubbles dissipate. If it starts to clear from the bottom of the glass first, this confirms that the cloudiness was nothing but air.Air in Water LinesIf cloudy water is accompanied by sputtering from the faucet, there may be air trapped in the water line. If you have had recent plumbing work done, the air may be in your home plumbing. This should clear as the water is used.Air may also become trapped in the line after Cal Water does work on a water main. This also will clear as the water is used, but if it does not or if the sputtering is accompanied by sediment in your water, please contact us.Testing Your WaterCal Water cannot recommend one water quality testing laboratory over another; however, if you would like to have your water tested, you should use a State-certified laboratory. More information is available on our Water Quality Testing Labs page.Additional InformationMore information on air trapped in water is available here: Video—Color in Water The USGS web site