Tap water safety
Water filters
- My water has contaminants detected above health guidelines. What does this mean? Do I need to use a filter?
- What kind of water filter should I buy?
- I’ve checked EWG’s Tap Water Database to see which chemicals were detected in my tap water and purchased an appropriate water filter. What else can I do to make my water better?
My water system
- Your database does not have any information about my water system. Where can I find this information?
- Where does my tap water come from?
- How does EWG’s Tap Water Database compare to my local water utility’s Consumer Confidence Report?
Drinking water contaminants
- Are some people more sensitive to water contaminants than others?
- Should I be concerned about lead in my tap water?
- My tap water has a strange smell, taste or color. Should I be concerned?
- My water smells like chlorine. What should I do?
- Where can I get my water tested?
- My community has issued a “boil water” alert. What does that mean?
EWG’s Tap Water Database
- What is the purpose of EWG’s Tap Water Database?
- Where did the data in EWG’s Tap Water Database come from?
- Does the EPA have a similar database available online?
Tap water safety
Is my tap water safe to drink?
In short: Legal does not mean safe.
Most community water systems get a passing grade from the federal government, even though contamination may be higher than what the latest science shows is safe. That’s because many drinking water regulations are out of date or based on outdated science. And there aren’t any regulations for many contaminants.
It’s important to understand that many of the risks posed by tap water contamination accumulate over a lifetime. And contaminants are studied – and their legal limits are set – one at a time, not based on exposure to multiple contaminants, which is what most people experience.
Some people, such as infants and pregnant people, may be at greater risk from the harms of tap water contaminants like lead.
For those who want or need better drinking water than what comes from the tap, EWG suggests buying a home water filter certified to remove or reduce the contaminants found in your tap water. EWG’s water filter guide can help you decide which is right for you.
Is bottled water safer than tap water?
In most situations, bottled water is not the answer.
One problem with bottled water is that you cannot be sure what you’re getting. Unlike public water suppliers, bottled water manufacturers are not required by law to disclose the levels of any contaminants in their products. Investigations have found that some bottled water is just tap water, filtered in some cases and not in others.
In addition to water contaminants that could come from the source water, bottled water may also be contaminated with micro- and nano-sized plastic and additives that can migrate from plastic packaging. Many of these additives have not been fully assessed for safety by the Food and Drug Administration, the agency that oversees food and beverage packaging.
Bottled water may be the appropriate choice in an emergency – after major storms or earthquakes, or a large-scale system failure.
Water filters
My water has contaminants detected above health guidelines. What does this mean? Do I need to use a filter?
A health guideline is the amount of a contaminant in drinking water that is not expected by scientists to pose any health risk, typically over a lifetime. Health guidelines are often lower than legal limits, which can be set based on outdated science or simply on the cost of treatment.
Tap water contaminants are not good for anyone. They are especially a concern for vulnerable populations and during sensitive periods of development, such as pregnancy and early childhood.
Certain contaminants can be removed only with advanced water filtration systems, but a simple countertop carbon filter is a great option for removing many types of contaminants. Check out EWG’s water filter guide for more info.
What kind of water filter should I buy?
Check out EWG’s water filter guide for help choosing a water filter that meets your needs. The guide can help you choose a filter on the basis of total cost, removal of specific contaminants or filter type.
I’ve checked EWG’s Tap Water Database to see which chemicals were detected in my tap water and purchased an appropriate water filter. What else can I do to make my water better?
One of the best things you can do to make your water better is to hold elected officials accountable.
Urge leaders to invest in better water treatment technology, create sustainable funding for water system improvements and protect source waters to keep pollution out of your water in the first place.
My water system
EWG’s Tap Water Database does not have any information about my water system. Where can I find this information?
Although EWG’s Tap Water Database shows data from nearly 50,000 community water systems, EWG was not able to obtain data for every water utility in every state.
If you seek water quality information for a system that is not in the database, contact that water utility directly.
You can also request the utility’s annual Consumer Confidence Report to investigate your system’s compliance with federal drinking water standards. The largest utilities are required by law to post their reports online, and other systems will provide a copy upon request.
But these annual reports tell only a part of the story. For more information, compare the levels detected by your utility to EWG’s health-based standards.
If you have a private well, consider getting it tested to find out the contaminants in it.
Where does my tap water come from?
Drinking water sources vary considerably across the country and even within communities.
Water utilities may pull water from surface water, including streams, rivers and lakes, or they may pump groundwater out of wells.
They may even use multiple sources that vary seasonally.
In addition, many systems buy water from other companies or large-scale suppliers.
For more information about where your tap water comes from, contact your local water utility.
How does EWG’s Tap Water Database compare to my local water utility’s Consumer Confidence Report?
The water quality reports that utilities are required by the EPA to give their customers every year show only a partial picture of what people are actually drinking.
These reports contain average levels and ranges detected for most contaminants, but they do not show spikes in contaminant levels that may have occurred during the year.
The reports also typically contain information only on federally regulated contaminants, because water utilities are not required to include any additional monitoring data they might have collected. The EPA requires only that utilities report regulated and unregulated chemicals included in special testing programs like Unregulated Contaminant Monitoring Rules.
Most importantly, annual utility reports do not list health guidelines or say whether some contaminants were found at levels that, though legal, may not be safe. Water utilities are only required to list violations of legal limits, which are often much higher than health guidelines.
A typical Consumer Confidence Report, compared to EWG’s Tap Water Database:
Consumer Confidence Reports compaired to EWG’s Tap Water Database
| Consumer Confidence Reports | EWG’s Tap Water Database | |
|---|---|---|
| Testing details | Shows yearly averages for contaminants detected and does not mention seasonal spikes in pollution. | Gives a precise picture of water quality throughout the year, listing full test results for each pollutant. |
| Safety levels | Compares pollution to regulatory limits, which are often based on political and economic compromise and do not fully protect public health. | Compares pollutants to levels scientists say are safe for everyone, including babies and pregnant women. |
| Number of contaminants | Typically show the detections of federally regulated contaminants, yet more than half of the contaminants found in tap water have no regulatory limit and may not be included. | Shows all test results for all monitored contaminants, not just those with legal limits. |
| How your water compares | Does not show how your water quality compares to that of other communities across the state and country. | Compares test results for all pollutants to state and national averages. |
Drinking water contaminants
Are some people more sensitive to water contaminants than others?
Yes. People with severely compromised immune systems, such as people undergoing chemotherapy, organ transplant recipients, people with HIV/AIDS or other immune system disorders, some elderly people, and infants and children can be particularly at risk.
People in these categories, or their caregivers, should take special precautions with tap water and seek advice from their health care providers about it.
The EPA, together with the Centers for Disease Control and Prevention, publishes recommendations to help people with compromised immune systems take extra precautions when it comes to their drinking water.
Should I be concerned about lead in my tap water?
First, ask your water provider whether tap water enters your home through a lead service line. Some cities also track where lead-based pipes are, or are suspected to be.
Testing water is important if you live in an area served by lead-based lines and if your local water company has detected lead in your neighborhood. (Even if the pipes leading to your home are not lead-based, there might be lead in household plumbing fixtures.)
If there is lead in your water, you can reduce it by flushing pipes with cold water each morning, using only cold water for cooking and using a home water filter. But these are just temporary solutions. The only permanent fix to chronic lead contamination is for communities to replace lead-based service lines, and for residents to replace lead pipes and fixtures in their homes. (Some cities have programs to help homeowners pay for such in-home replacements.)
For more information about lead in drinking water and tips to decrease your family’s exposure, read the Tap Water Database’s lead section.
My tap water has a strange smell, taste or color. Should I be concerned?
Unpleasant smells, colors and tastes do not necessarily mean your water is unsafe to drink. But these can be important indicators of potential safety problems. EWG recommends that you contact your local water supplier to investigate these conditions. If you have a private well, we recommend getting it tested.
If the smell, color or taste is related to excessive minerals in your water, a home water filter can help solve the issue. EWG has developed an extensive water filter guide to help you choose an appropriate filter.
Another source of an unusual water smell could be the growth of algae in the source water used by the water utility. Algae toxins can be removed by conventional water treatment, but treatment may not be as effective when there are high levels. If your water utility reports algae contamination, you may need to temporarily use bottled water.
My water smells like chlorine. What should I do?
Many tap water systems use chlorine to disinfect water. Water must be disinfected to get rid of dangerous pathogens and make it safe to drink. Sometimes utilities use extra chlorine for safety after a big rainstorm or for annual maintenance.
Although essential for protecting public health from waterborne diseases, disinfectants like chlorine also combine with organic matter to create carcinogenic chemicals called disinfection byproducts in tap water.
To deal with excess chlorine and help reduce disinfection byproducts from your water, you may want to use a home water filter that is effective at removing these contaminants. EWG’s water filter guide can help you find the right one.
Where can I get my water tested?
Many labs around the country test water for common contaminants. We recommend that you choose one that has been certified by the state to test drinking water. The EPA’s website has additional information and resources to help you choose an appropriate lab.
My community has issued a “boil water” alert. What does that mean?
If a water system has issued a boil water alert, it is likely that one or more microbiological contaminants were discovered at levels exceeding those allowed by the EPA and that are considered unsafe for people to drink.
The water system must warn customers of the potential danger, then take appropriate corrective action. It must continue to monitor its water supply and notify customers when it has remedied the problem. Throughout that process, you should follow guidance issued by your water system.
Under the provisions of the Safe Drinking Water Act, water systems that serve more than 25 people are required to test their water regularly for a wide variety of contaminants, including microorganisms.
EWG's Tap Water Database
What is the purpose of EWG’s national Tap Water Database?
EWG developed the Tap Water Database because we believe everyone has the right to know what’s in their tap water.
Although the government requires utilities to make some information available to the public, utility reports often don’t tell the full story.
EWG’s Tap Water Database is the only free online consumer resource that analyzes drinking water quality purely with respect to human health.
Users can search by ZIP code to find their water utility, see the detected contaminants in their water and learn how the levels of contaminants in their water compare to health guidelines.
Where did the data in your database come from?
EWG requested water contaminant data from public and environmental health agencies in all 50 states and the District of Columbia. We received more than 34 million records and compiled them. The database also includes water quality data collected as part of the EPA’s Unregulated Contaminants Monitoring Rule.
EWG released the first version of the database in 2005, with updates in 2009, 2017, 2019, 2021 and 2025.
Does the EPA have a similar database available online?
No, but it should.
In fact, the 1996 Safe Drinking Water Act Amendments require the EPA to produce such a public service, stating: “Not later than 3 years after the date of enactment of the Safe Drinking Water Act Amendments of 1996, the Administrator shall assemble and maintain a national drinking water contaminant occurrence database, using information on the occurrence of both regulated and unregulated contaminants in public water systems.”
Nearly 30 years later, the EPA still has not made this data public in a readily accessible or easy to understand manner. Until the federal government steps up, EWG’s Tap Water Database will continue to fill this important data gap.