EWG's Tap Water Database — 2019 UPDATE



James Fork Regional Water District

Fluoride occurs naturally in surface and groundwater and is also added to drinking water by many water systems. Read More.

Fluoride has been promoted as a chemical that reduces dental cavities. Yet it is now well-established that fluoride primarily exerts its protective effects through topical mechanisms, such as sodium fluoride in toothpaste and mouthwash. In contrast, long-term ingestion of fluoride in water increases dental fluorosis, which includes mottling, pitting and weakening of the teeth. EPA's maximum legal limit is set at 4 parts per million (ppm) to prevent skeletal fluorosis, a condition where bones become brittle and more susceptible to fractures, although these effects may occur at lower doses.

Even fluoride levels of 0.7 ppm, the amount of fluoride in drinking water recommended by the U.S. Public Health Service, can result in too much fluoride for bottle-fed babies. EWG recommends that caregivers mix baby formula with fluoride-free water. The National Toxicology Program is investigating the potential for low doses of fluoride to alter thyroid function and childhood brain development.





Samples exceeding legal limit (MCL)


Samples exceeding
health guidelines

Testing results - average by year

YearAverage resultSamples takenDetectionsRange of results
20120.744 ppm1412ND - 0.930 ppm
20130.868 ppm13130.820 ppm - 0.960 ppm
20140.668 ppm13130.540 ppm - 0.820 ppm
20150.781 ppm13130.590 ppm - 0.880 ppm
20160.791 ppm13130.640 ppm - 0.940 ppm
20170.768 ppm13130.590 ppm - 0.830 ppm

ppm = parts per million

State and national drinking water standards and health guidelines

EPA Maximum Contaminant
Level (MCL) 4 ppm

ppm = parts per million

All test results

Date Lab ID Result
2012-01-141203000060.790 ppm
2012-02-061204500390.820 ppm
2012-03-141208700060.830 ppm
2012-04-111211400070.820 ppm
2012-05-101214200130.810 ppm
2012-06-251218400030.920 ppm
2012-07-061219800050.860 ppm
2012-08-141223400230.910 ppm
2012-09-201227600170.910 ppm
2012-10-151229600080.920 ppm
2012-11-051232400210.930 ppm
2012-12-031234500220.900 ppm
2013-01-021301400210.910 ppm
2013-01-291303100170.960 ppm
2013-02-201306300090.880 ppm
2013-03-161308500190.880 ppm
2013-04-101311300030.860 ppm
2013-05-281316100020.820 ppm
2013-06-251318300260.850 ppm
2013-07-051319700200.840 ppm
2013-08-071322500410.850 ppm
2013-09-091325900240.820 ppm
2013-10-161330300090.840 ppm
2013-11-191333000190.890 ppm
2013-12-121335200310.880 ppm
2014-01-231403000610.820 ppm
2014-01-271403000180.700 ppm
2014-02-251406900180.660 ppm
2014-03-171409000390.660 ppm
2014-04-011411500030.590 ppm
2014-05-091414700050.540 ppm
2014-06-051416700300.630 ppm
2014-07-251421600110.660 ppm
2014-08-121423000220.690 ppm
2014-09-191427200100.660 ppm
2014-10-13Y1430000090.720 ppm
2014-11-25Y1434200120.610 ppm
2014-12-23Y1501300100.750 ppm
2015-01-06Y1501300510.630 ppm
2015-01-20Y1502300010.780 ppm
2015-02-20Y1506100150.880 ppm
2015-03-24Y1509600040.750 ppm
2015-04-17Y1511400140.590 ppm
2015-05-21Y1515500500.840 ppm
2015-06-15Y1517400290.880 ppm
2015-07-15Y1520800050.790 ppm
2015-08-05Y1522600290.770 ppm
2015-09-23Y1527800020.820 ppm
2015-10-21Y1530300190.760 ppm
2015-11-28Y1534100160.840 ppm
2015-12-09Y1535200230.820 ppm
2016-01-10Y1602000300.810 ppm
2016-01-14Y1601500040.770 ppm
2016-02-03Y1604700140.720 ppm
2016-03-30Y1609500020.800 ppm
2016-04-24Y1612400190.780 ppm
2016-05-20Y1615800150.660 ppm
2016-06-29Y1619300010.940 ppm
2016-07-18Y1620700300.860 ppm
2016-08-16Y1624200040.730 ppm
2016-09-22Y1627800010.840 ppm
2016-10-26Y1630800170.890 ppm
2016-11-28Y1634200010.840 ppm
2016-12-21Y1636400100.640 ppm
2017-01-20Y1703500170.670 ppm
2017-01-31Y1703300020.710 ppm
2017-02-27Y1707200080.830 ppm
2017-03-28Y1710000080.800 ppm
2017-04-19Y1712100070.830 ppm
2017-05-15Y1714200310.720 ppm
2017-06-06Y1717000060.800 ppm
2017-07-26Y1721900190.780 ppm
2017-08-23Y1724800070.590 ppm
2017-09-25Y1727600260.820 ppm
2017-10-11Y1729600030.820 ppm
2017-11-21Y1733800280.830 ppm
2017-12-19Y1736100310.780 ppm