How to Find Out What’s Actually in Your Tap Water

Most people buy a water filter the way they buy a smoke alarm. Something in the news made them uneasy, so they bought the thing that seemed most protective and moved on. Which is how you end up with a pitcher that’s excellent at chlorine and blind to the nitrate that’s actually in your supply.

You can skip the guessing. The information is public, it’s free, and it takes about ten minutes.

Short answer: every community water system in the US has to send customers a Consumer Confidence Report every year, by July 1. It lists what was detected and at what levels. The EWG Tap Water Database translates the same data into plain language by ZIP code. Neither one can tell you about lead, because lead usually comes from the pipes between the main and your tap, so that needs either your utility’s service line inventory or a home test.

The report your utility already owes you

The Consumer Confidence Report is required under the Safe Drinking Water Act. Every community water system has to produce one annually and deliver it to customers by July 1. Search your utility’s name plus “consumer confidence report” and it’s almost always a PDF on the first page of results.

What you’re looking for is the detections table: the contaminant, the level found, and the legal limit alongside it. Anything detected above its limit is a violation and the report has to say so.

Here’s the part that trips people up, though. A result inside the legal limit is not the same as a result with no health significance. Some limits were set decades ago, some were set with treatment cost factored in, and EPA’s own health-based goals for certain contaminants sit at zero while the enforceable limit sits higher. “No violations” means your utility complied. It doesn’t mean the water is free of things you might rather not drink.

EWG’s database, and why its numbers look scarier

The EWG Tap Water Database takes utility testing data and presents it by ZIP code in language a normal person can read. It’s the fastest way to see what your area’s water has historically contained.

It also compares results against EWG’s own health guidelines rather than the federal legal limits, which are stricter. That’s why a utility can report full compliance while EWG shows several contaminants “above guideline” for the same water. Both statements are true. They’re answering different questions: one is “did they break the law”, the other is “what would a cautious health standard say”.

Read it as a map of what to investigate, not a verdict. Then check the actual CCR for your current numbers, because the database can lag.

Well water: nobody is testing it for you

If you’re on a private well, none of the above applies. There’s no utility, no annual report, and no legal requirement that anyone check your water at all. Testing is entirely on you.

That’s worth saying plainly because well owners are the group most likely to have a specific, fixable problem and least likely to know. Nitrate from agricultural runoff, arsenic from local geology, and bacteria after flooding are the usual suspects, and none of them announce themselves by taste or smell. Your county health department can usually point you to a certified lab, and annual testing is the standard advice.

The one thing no report can tell you: your own pipes

Utility testing samples the system. It cannot sample the pipe running into your house, or the plumbing inside it, and lead is almost always a plumbing problem rather than a source-water problem.

There’s a real development here. Under EPA’s lead and copper rule changes, water systems had to compile an inventory of their service lines and submit it by October 16, 2024, make it publicly accessible, and notify people served by lines that are lead or of unknown material. Systems serving more than 50,000 people have to post the inventory online. So for many households, “is my service line lead” is now a question with a published answer. Search your utility’s name plus “service line inventory.”

An “unknown” entry is common and is not reassurance. It means nobody has verified it yet.

When a home test is worth the money

Buy a test when the answer would change what you do. If your service line is lead or unknown, if you’re on a well, if you live in older housing stock, or if the CCR shows something specific you want to confirm at your own tap, a certified lab test is the honest way to know.

Skip the free strip that comes bundled with a filter. It’s a marketing device, and it typically measures total dissolved solids, which tells you almost nothing about safety. High TDS can be harmless minerals. Low TDS doesn’t mean an absence of PFAS or lead. A mail-in kit from an accredited lab costs more and actually answers the question.

Once you know what you’re dealing with, the filter decision becomes arithmetic instead of anxiety. Carbon and reverse osmosis fail at different things, which we lay out in reverse osmosis versus carbon filters, and the certification on the box is what ties a product to your specific contaminant, covered in what the NSF standards mean. Our vetted picks are here.

Frequently asked questions

How do I get my Consumer Confidence Report?

Search your water utility’s name plus “consumer confidence report” or “water quality report.” Community water systems are required to deliver it to customers annually by July 1, and nearly all of them publish it as a PDF. If you rent and never see one, your landlord or building manager receives it, and you can request it directly from the utility.

Does “no violations” mean my water is safe?

It means your utility met the enforceable legal limits, which is not quite the same claim. Some limits are decades old, and EPA’s health-based goals for certain contaminants are set at zero while the enforceable limit is higher. Compliance is a floor. If you want a stricter reading of the same data, compare against EWG’s health guidelines.

Are the free test strips that come with filters any good?

Generally no. Most measure total dissolved solids, which lumps harmless minerals in with everything else and says nothing about lead, PFAS, nitrate or bacteria. Water can show low TDS and still contain contaminants that matter. If you want a real answer, use a certified laboratory test.

How do I find out if my home has a lead service line?

Start with your utility’s service line inventory, which systems had to submit by October 16, 2024 and make publicly accessible, with larger systems posting it online. If your line is listed as lead or unknown, or your home predates the 1986 lead plumbing restrictions, a certified lab test at your own tap is the way to confirm what’s reaching you.

Related reading

Once you know what’s in your water, the next questions are mechanical: reverse osmosis versus carbon filters, what the NSF certifications actually cover, and whether a Brita does anything about PFAS. Then see the best water filters for systems that clear the bar.