Learn About Your Tap Water

Learn how to read water reports, understand EPA standards, and make informed decisions about your tap water.

39 articles

Deep-dives on specific water contaminants including lead, PFAS, arsenic, and more. Learn about health effects and removal methods.

5 articles

NSF certification explained, filter comparisons, and expert recommendations for removing specific contaminants.

15 articles

City-specific water quality analysis, contamination issues, and local recommendations.

3 articles

Home test kits, certified lab reviews, and guidance on when and how to test your tap water.

2 articles

Running the tap clears water that sat in your pipes, but how long matters, and a quick rinse can make lead worse. The answer for your home, and what it costs.

Wash a reusable water bottle every day, take the lid apart, and let every piece dry before you reassemble it. In a peer-reviewed test of 90 used bottles, 60% were above 500 bacteria per milliliter. Saliva is a big part of the reason, and filtered, RO and bottled water carry little or no disinfectant to slow regrowth. Here is the routine that works, how to clean the straw, and what vinegar, baking soda and bleach actually do.

EPA research puts high-pressure membranes such as reverse osmosis typically above 90 percent removal across a wide range of PFAS, shorter-chain ones included. A PFAS claim for a given model is rarer: of 547 listings certified to NSF/ANSI 58, 39 carry a PFAS claim. Here is what each number means and how to check the model you own.

Softened water is safe for almost everyone to drink — an ion-exchange softener adds roughly 7.9 mg/L of sodium for every grain per gallon of hardness it removes, which in very hard water lands the finished glass near 159 mg/L, about 14% of a day's sodium. The harder question is what was in the water beforehand: every community water system in America is required by federal law to measure sodium, is held to no limit whatsoever, and is not required to tell you the answer.

Since 2018, Pennsylvania schools that tested their water had to report any detectable lead. The July 2026 budget raised that to 5 parts per billion. We pulled the state's own spreadsheet — 999 readings from 764 school buildings — and found a median of 26.6 ppb, a maximum of 8,768 ppb, and only 67 of Pennsylvania's 500 school districts reporting anything at all in seven years. Meanwhile Michigan, Indiana, and Minnesota each expanded public reporting.

Test a private well every year for total coliform bacteria and nitrate, every three to five years for the contaminants your local geology carries, and immediately after flooding, repairs, or any change in taste. That is what EPA, the CDC, and state agencies converge on — and in 47 of 51 US jurisdictions no law will ever require any of it. Priced at a state laboratory, the whole schedule costs about $70 a year.