The vast majority of Americans can learn about every potentially harmful chemical in their drinking water and what scientists say are the safe levels of those contaminants. The Environmental Working Group says its new national Tap Water Database is the most complete source available on the quality of U.S. drinking water, aggregating and analyzing data from almost 50,000 public water systems in all 50 states and the District of Columbia.

The database includes reports on tap water from the Algoma, Kewaunee and Luxemburg water works, as well as Lakeview Heights Mobile Home Park in Algoma.

The organization claims a reputation for ambitious data-mining research projects that shake up policy debates and consumer markets. EWG’s online Farm Subsidy Database, listing millions of subsidy recipients, and its Skin Deep guide to over 70,000 personal care products, draw tens of millions of visitors every year.

By entering their zip code or local utility’s name, users of the new database will find all contaminants detected in tests by the utilities themselves and reported to federal or state authorities. Instead of comparing the levels of pollutants to the legal limits set by regulatory agencies – often the result of political and economic compromise, or based on outdated studies – EWG says its guide relies on what the best and most current science finds are the levels that will fully protect public health, especially that of infants, children, pregnant women and other vulnerable populations.

“Americans deserve the fullest picture possible of what’s in their tap water,” said EWG President Ken Cook. “But they won’t get that information from the government or, in many cases, from their utilities. The only place they’ll find that is EWG’s drinking water report.”

The vast majority of utilities are in compliance with federal regulations, but their water still often contains contaminants in concentrations exceeding the levels that scientists say pose health risks.

EWG researchers spent the last two years collecting data from state agencies and the EPA for drinking water tests conducted from 2010 to 2015 by 48,712 water utilities in all 50 states and D.C. All told, the utilities tested for approximately 500 different contaminants and found 267.

Click here to reach the EWG Tap Water Database home page.