No map marker is shown for a known source of water
Map markers on this website, such as the local water-quality maps, indicate where water has been tested or observed and recorded in some formal way. They do not indicate all known sources of water, only water for which records are available. It’s also possible that water data is recorded in places we have not yet included in our “water-quality explorer” tools. Yet!
[Editor’s note: we wish the community and household wells of our childhood were included!]
“No results recorded” on reports
When we find a record stating a test was performed, we include that fact in our reports. Sometimes there are no recorded results for the test. This might occur for a number of reasons. For example, the test wasn’t actually performed, results were inconclusive or unreliable, someone neglected to record the results, etc.
I see a web page saying just “502 Bad Gateway”
That seems to happen sometimes when using the site’s map to explore local water quality. The remote server might be overloaded (or just very slow). When we have run into that message and simply tried again a few hours later, or the next day, the problem seems to go away and the expected content loads normally.
Why are you doing this project?
We want to make it easier for more people to learn about the water in their communities, whether they’re urban, suburban, or rural. A recent study concludes that 77% of Americans who are not on well water do not know the source of their supply. We aim to provide easy ways to get such information, and more. Of course, if our work also helps agencies and leaders to better understand and manage these shared resources, we are even happier.
Can I trust the information on this website?
We retrieve water-quality data from trustworthy sources that we identify in the reports provided here. They may also identify who collected the samples that were analyzed.
How accurate are the water-quality tests?
The reports we display may include data from multiple sources, which the reports identify. While we may have no direct knowledge of the individual data providers, it’s informative to see how the U.S. EPA certifies water-testing laboratories.
By necessity, we rely upon responsible organizations, scientists, technicians, and others working at many facilities. If you find a report where the source of the data is not clear, or it appears to be unreliable, contact the reporting organization shown.
How current is the water data shown in the site’s water maps and water-quality reports?
Where test dates are reported, they should be shown in our reports.
We cannot vouch for how recent the data is for any particular location, but we can share the following practices of these major data providers:
USGS NWIS — Water-resource data is collected from approximately 1.5 million sites in all USA states, the District of Columbia, Puerto Rico, the Virgin Islands, Guam, American Samoa, and the Commonwealth of the Northern Mariana Islands. NWIS is updated every 24 hours. Data recently added to NWIS may not be immediately accessible. Data is available for each location since the beginning of the database.
USEPA STORET — A data warehouse for water quality, biological, and physical data used by state environmental agencies, EPA, other federal agencies, universities, private citizens, and others. STORET is updated weekly on Thursday evening. Data recently added to STORET may not be immediately accessible through the WQP. The portal will return data from each location since the beginning of the database.
Should I be alarmed if certain substances/characteristics show up in my water-supply report?
Items of potential concern in a water sample might not necessarily indicate danger. And it’s not only “what is there,” but also “how much of it is there?” The need for concern can only be evaluated by referring to authoritative scientific and public-health authorities.
We are not medical or public health experts. This site does not make determinations as to threat, risk, healthfulness, danger, etc. We may provide access to third-party sources of such information and, in some cases, we may summarize such information on this site with appropriate credit.
The USA EPA Substance Registry Services (SRS) is the Environmental Protection Agency’s (EPA) central system for information about substances that are tracked or regulated by EPA or other sources. The agency intends for it to be the authoritative resource for basic information about chemicals, biological organisms, and other substances of interest to EPA and its state and tribal partners.
The system provides a common basis for the identification of and information about:
- Biological organisms
- Physical properties
- Miscellaneous objects