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UCMR (Unregulated Contaminant Monitoring Rule) Data
Massachusetts Water Resources Authority


Cryptosporidium and Giardia information

Research for New Regulations

The US Environmental Protection Agency (EPA) periodically requires water systems across the country to conduct monitoring for substances that may be present in drinking water to help understand their national occurrence as part of the process of deciding whether to regulate these substances. Under the Safe Drinking Water Act Amendments, EPA is required once every five years to develop a list of up to 30 new contaminants that must be monitored by public water systems.

MWRA collected samples during 2013, 2014, and 2015 at locations throughout our service area for 21 substances and for 7 hormones. Even with the extremely sensitive test methods used capable of detecting some substances at parts per trillion levels, we expected to find very few of the substances that we were required to test for due to MWRA’s highly protected watershed and reservoirs. Only 5 of the 21 substances tested for in 2013, 2014, and 2015 were detected, and all were at extremely low levels. None of the seven hormones tested for in 2014 and 2015 were detected.

Here is the complete list of 21 substances plus 7 hormones:


Substances (21)
1,2,3-trichloropropane  strontium
bromomethane  total chromium
chloromethane hexavalent chromium
bromochloromethane chlorate
chlorodifluoromethane perfluorooctanesulfonic acid
1,3-butadiene perfluorooctanoic acid
1,1-dichloroethane perfluorobutanesulfonic acid
1,4-dioxane perfluorohexanesulfonic acid
vanadium perfluoroheptanoic acid
molybdenum perfluorononanoic acid


Hormones (7)
17-a-Ethynylestradiol 17-b-Estradiol
Estrone 4-androstene-3,17-dione
Estriol Equilin

More information on these substances and UCMR3 can be found at at on the US EPA web site.


MWRA UCMR 3 Test Results 2013-2015*
Fully Supplied Communities Chicopee Valley Aqueduct
(CVA) Communities
Partially Supplied Communities
2015 2015 2015
2014 -- 2014
2013 -- --

* UCMR 3 (2013-2015) monitoring is complete. UCMR 4 (2018-2020) monitoring is underway.

How will this data be used?

EPA will collect and analyze data for all three years and from systems all across the country to develop an understanding of the occurrence, level and distribution of these substances in drinking water.  That data, along with information on potential health effects and water treatment effectiveness will be used by EPA to determine if any new regulations are needed. 


Updated May 31, 2018

Posted June 3, 2016

Historic Withdrawls Reservoir Levels