PHY3 Drinking water quality: Percentage of children served by community water systems that did not meet all applicable health-based drinking water standards, 1993–2020

excel icon PHY3 Excel Table

Characteristic 1993 1994 1995 1996 1997 1998 1999 2000 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 2011 2012 2013 2014 2015 2016 2017 2018 2019 2020 2021
Type of standard violated
All health-based standards 19.6 15.7 11.1 10.2 9.9 8.8 7.9 8.5 5.2 11.6 8.5 8.9 12.1 11.2 8.3 6.8 7.6 7.8 5.2 8.4 6.7 8.0 9.2 5.5 8.5 8.1 7.4 6.4 7.0
Lead and copper 2.9 1.9 2.2 2.0 2.0 1.8 1.6 1.3 1.1 0.8 0.7 0.9 0.8 0.6 0.4 0.5 0.8 0.2 0.1 0.1 0.1 0.1 0.2 0.3 0.4 0.7 0.7 0.8 0.9
Total coliforms 10.4 8.6 4.3 4.5 3.8 3.1 3.3 3.1 2.3 2.7 3.2 3.7 3.6 2.9 2.6 2.4 2.6 2.6 2.6 2.5 2.8 4.1 3.1 0.4 0.6 0.4 0.3 0.3 0.4
Chemical and radionuclide 0.9 0.8 1.4 0.8 1.1 0.9 0.7 0.7 0.6 0.7 0.7 1.1 1.0 1.3 1.2 1.1 1.2 0.9 0.9 0.7 0.5 0.5 0.4 0.4 0.4 0.3 0.3 0.6 0.2
Surface water treatment 6.5 5.5 3.9 3.5 3.3 2.7 2.4 3.1 1.2 5.5 1.5 1.5 4.8 4.6 2.7 1.3 1.9 2.9 0.6 4.1 0.9 0.6 1.6 1.0 4.4 4.6 4.0 3.6 4.8
Nitrate/nitrite 0.2 0.1 0.2 0.2 0.4 0.8 0.3 0.7 0.2 0.6 0.3 0.1 0.1 0.6 0.2 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.5 0.6 0.1 0.1 0.0 0.0 0.0
Disinfection byproducts 1.5 2.9 2.6 2.2 1.7 1.5 1.5 1.3 1.4 1.1 1.2 2.5 3.0 3.9 3.2 3.0 2.6 2.3 1.4 1.0
— Not available.
NOTE: Revisions to the following standards were made between 2002 and 2006: disinfection byproducts (2002 for larger systems and 2004 for smaller systems), surface water treatment (2002), radionuclides (2003), and arsenic (included in the chemical and radionuclide category in 2006). Revisions to the Total Coliform Rule took effect in 2016. No other revisions to the standards have taken effect during the period of trend data (beginning with 1993). Indicator values reflect the standards in place for each year depicted. Some estimates have been revised since previous publication in America's Children. Values for years prior to 2018 have been recalculated based on updated data in the Safe Drinking Water Information System.
SOURCE: U.S. Environmental Protection Agency, Office of Water, Safe Drinking Water Information System.