Chlorate

Lyon County Rural Water District 2

NOTE: Lyon County Rural Water District 2 purchases water from City of Emporia which is required to test for chlorate. Sample information shown below was taken by City of Emporia.

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.

MORE ABOUT THIS CONTAMINANT

Samples

Samples exceeding legal limit (MCL)

Samples exceeding
health guidelines

Testing results - average by year

Year	Average result	Samples taken	Range of results
2013	ND	8	ND
2014	ND	8	ND
2015	N/A	0	N/A
2016	N/A	0	N/A
2017	N/A	0	N/A
2018	N/A	0	N/A
2019	N/A	0	N/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: Lyon County Rural Water District 2 purchases water from City of Emporia which is required to test for chlorate. Sample information shown below was taken by City of Emporia.

Date	Lab ID	Result
2014-02-28	2984516	ND
2014-02-28	2984521	ND
2014-05-22	3032466	ND
2014-05-22	3032454	ND
2014-08-28	3094125	ND
2014-08-28	3094158	ND
2014-11-19	3142668	ND
2014-11-19	3142660	ND