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EWG's Tap Water Database — 2019 UPDATE

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Chlorate

Sun Valley Gid

NOTE: Sun Valley Gid purchases water from Truckee Meadows Water Authority which is required to test for chlorate. Sample information shown below was taken by Truckee Meadows Water Authority.

Chlorate forms in drinking water as a byproduct of disinfection. Chlorate impairs thyroid function, making chlorate exposure most harmful during pregnancy and childhood. Read More.

In 2002, California scientists proposed an advisory value, called an action level, for chlorate at 200 parts per billion. Between 2013 and 2015, the EPA collected data through the Unregulated Contaminant Monitoring Rule program and found that over 15 percent of water tests from 38 percent of utilities had chlorate levels above a health-protective concentration, which federal scientists defined as 210 parts per billion, nearly equivalent to the California advisory value.

Click here to read more about disinfection byproducts.

 

45

Samples

0

Samples exceeding legal limit (MCL)

0

Samples exceeding
health guidelines

Testing results - average by year

 
YearAverage resultSamples takenDetectionsRange of results
2012N/A00N/A
201388.9 ppb8823.0 ppb - 130.0 ppb
201463.5 ppb1110ND - 89.0 ppb
2015N/A00N/A
2016N/A00N/A
2017N/A00N/A

ppb = parts per billion

State and national drinking water standards and health guidelines

EWG Health Guideline 210 ppb

The EWG Health Guideline of 210 ppb for chlorate was defined by the Environmental Protection Agency as a benchmark for testing under the Unregulated Contaminant Monitoring Rule program. This health guideline protects against hormone disruption.

ppb = parts per billion

All test results

NOTE: Sun Valley Gid purchases water from Truckee Meadows Water Authority which is required to test for chlorate. Sample information shown below was taken by Truckee Meadows Water Authority.

Date Lab ID Result
2013-05-20201305210061AM67.0 ppb
2013-05-20201305210275AM48.0 ppb
2013-05-20201305210066AM47.0 ppb
2013-05-20201305210059AMND
2013-05-22201305230338AM50.0 ppb
2013-05-22201305230342AM43.0 ppb
2013-05-22201305230289AM38.0 ppb
2013-05-22201305230335AMND
2013-06-04201306050241AMND
2013-06-04201306050256AM88.0 ppb
2013-06-04201306050182AMND
2013-06-11201306120169AM32.0 ppb
2013-06-11201306120229AM96.0 ppb
2013-06-11201306120227AM34.0 ppb
2013-06-11201306120163AM53.0 ppb
2013-06-11201306120172AM73.0 ppb
2013-06-11201306120213AM36.0 ppb
2013-06-19201306200237AM130.0 ppb
2013-06-19201306200268AMND
2013-06-19201306200241AM26.0 ppb
2013-06-19201306200126AMND
2013-06-19201306200250AMND
2013-06-19201306200243AM83.0 ppb
2013-06-19201306200239AMND
2013-06-24201306250077AM77.0 ppb
2013-06-25201306260231AM45.0 ppb
2013-06-25201306260226AM44.0 ppb
2013-06-27201306280176AMND
2013-09-17201309200267AM150.0 ppb
2013-09-17201309200263AM170.0 ppb
2013-09-17201309200279AM140.0 ppb
2013-11-25201311270060AM100.0 ppb
2013-12-16201312180499AM110.0 ppb
2013-12-17201312180531AM130.0 ppb
2014-03-05201403070277AM67.0 ppb
2014-03-05201403070313AM69.0 ppb
2014-04-22201404250162AM45.0 ppb
2014-04-22201404250189AM89.0 ppb
2014-04-22201404250157AMND
2014-04-22201404250176AM84.0 ppb
2014-04-29201405020257AM72.0 ppb
2014-04-29201405020173AM71.0 ppb
2014-04-29201405020265AM66.0 ppb
2014-04-29201405020169AM64.0 ppb
2014-06-09201406110932AM71.0 ppb