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EWG's Tap Water Database — 2021 UPDATE

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Merrimack Village District

EWG's drinking water quality report shows results of tests conducted by the water utility and provided to the Environmental Working Group by the New Hampshire Department of Environmental Services, as well as information from the U.S. EPA Enforcement and Compliance History database (ECHO). For the latest quarter assessed by the U.S. EPA (January 2021 - March 2021), tap water provided by this water utility was in compliance with federal health-based drinking water standards.

Utility Details

  • Merrimack, New Hampshire
  • Serves: 25,000
  • Data available: 2014-2021*
  • Source: Groundwater
  • * 2020/2021 testing is for chemicals in EPA's Fourth Unregulated Contaminant Monitoring Rule (UCMR-4) only.

Contaminants Detected

10

EXCEED
EWG HEALTH
GUIDELINES

30 Total Contaminants

  • Legal does not necessarily equal safe. Getting a passing grade from the federal government does not mean the water meets the latest health guidelines.
  • Legal limits for contaminants in tap water have not been updated in almost 20 years.
  • The best way to ensure clean tap water is to keep pollution out of source water in the first place.

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Contaminants Detected

Bromodichloromethane

Potential Effect: cancer37x EWG'S HEALTH GUIDELINE
THIS UTILITY2.21 ppb
EWG HEALTH GUIDELINE0.06 ppb
NO LEGAL LIMIT
DETAILS
X

Bromodichloromethane

more about
this contaminant

Bromodichloromethane, one of the total trihalomethanes (TTHMs), is formed when chlorine or other disinfectants are used to treat drinking water. Bromodichloromethane and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy. Click here to read more about disinfection byproducts.

Bromodichloromethane was found at 37 times above EWG's Health Guideline.

EWG Health Guideline

0.06 ppb or less

This Utility

2.21 ppb

National Average

5.79 ppb

State Average

2.96 ppb
NO LEGAL LIMIT
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2017-2019.
ppb = parts per billion

Health Risks

The EWG Health Guideline of 0.06 ppb for bromodichloromethane was proposed in 2018 by the California Office of Environmental Health Hazard Assessment as a one-in-a-million lifetime risk of cancer. Values greater than one-in-a-million cancer risk level can result in increased cancer cases above one in a million people.

Pollution Sources

Treatment Byproducts

Filtering Options

Activated Carbon

Reverse Osmosis

Chloroform

Potential Effect: cancer9.1x EWG'S HEALTH GUIDELINE
THIS UTILITY3.64 ppb
EWG HEALTH GUIDELINE0.4 ppb
NO LEGAL LIMIT
DETAILS
X

Chloroform, one of the total trihalomethanes (TTHMs), is formed when chlorine or other disinfectants are used to treat drinking water. Chloroform and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy.

Chloroform was found at 9.1 times above EWG's Health Guideline.

EWG Health Guideline

0.4 ppb or less

This Utility

3.64 ppb

National Average

15.5 ppb

State Average

12.7 ppb
NO LEGAL LIMIT
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2017-2019.
ppb = parts per billion

Health Risks

The EWG Health Guideline of 0.4 ppb for chloroform was proposed in 2018 by the California Office of Environmental Health Hazard Assessment as a one-in-a-million lifetime risk of cancer. Values greater than one-in-a-million cancer risk level can result in increased cancer cases above one in a million people.

Pollution Sources

Treatment Byproducts

Filtering Options

Activated Carbon

Reverse Osmosis

Chromium (hexavalent)

Potential Effect: cancer7.7x EWG'S HEALTH GUIDELINE
THIS UTILITY0.154 ppb
EWG HEALTH GUIDELINE0.02 ppb
NO LEGAL LIMIT
DETAILS
X

Chromium (hexavalent)

more about
this contaminant

Chromium (hexavalent) is a carcinogen that commonly contaminates American drinking water. Chromium (hexavalent) in drinking water may be due to industrial pollution or natural occurrences in mineral deposits and groundwater. Read more about chromium (hexavalent).

Chromium (hexavalent) was found at 7.7 times above EWG's Health Guideline.

EWG Health Guideline

0.02 ppb or less

This Utility

0.154 ppb

National Average

0.484 ppb

State Average

0.0731 ppb
NO LEGAL LIMIT
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2013-2019.
ppb = parts per billion

Health Risks

The EWG Health Guideline of 0.02 ppb for chromium (hexavalent) was defined by the California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer.

Pollution Sources

Industry

Naturally Occurring

Filtering Options

Reverse Osmosis

Ion Exchange

Dibromochloromethane

Potential Effect: cancer11x EWG'S HEALTH GUIDELINE
THIS UTILITY1.12 ppb
EWG HEALTH GUIDELINE0.1 ppb
NO LEGAL LIMIT
DETAILS
X

Dibromochloromethane

more about
this contaminant

Dibromochloromethane, one of the total trihalomethanes (TTHMs), is formed when chlorine or other disinfectants are used to treat drinking water. Dibromochloromethane and other disinfection byproducts increase the risk of cancer and may cause problems during pregnancy. Click here to read more about disinfection byproducts.

Dibromochloromethane was found at 11 times above EWG's Health Guideline.

EWG Health Guideline

0.1 ppb or less

This Utility

1.12 ppb

National Average

3.29 ppb

State Average

1.01 ppb
NO LEGAL LIMIT
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2017-2019.
ppb = parts per billion

Health Risks

The EWG Health Guideline of 0.1 ppb for dibromochloromethane was proposed in 2018 by the California Office of Environmental Health Hazard Assessment as a one-in-a-million lifetime risk of cancer. Values greater than one-in-a-million cancer risk level can result in increased cancer cases above one in a million people.

Pollution Sources

Treatment Byproducts

Filtering Options

Activated Carbon

Reverse Osmosis

Haloacetic acids (HAA5)†

Potential Effect: cancer103x EWG'S HEALTH GUIDELINE
THIS UTILITY10.3 ppb
EWG HEALTH GUIDELINE0.1 ppb
LEGAL LIMIT60 ppb
DETAILS
X

Haloacetic acids (HAA5)

more about
this contaminant

Haloacetic acids are formed when disinfectants such as chlorine are added to tap water. The group of five haloacetic acids regulated by federal standards includes monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid and dibromoacetic acid.

Haloacetic acids (HAA5) was found at 103 times above EWG's Health Guideline.

EWG Health Guideline

0.1 ppb or less

This Utility

10.3 ppb

Legal Limit

60 ppb

National Average

17.1 ppb

State Average

12.6 ppb
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2017-2019.
ppb = parts per billion

Health Risks

The EWG Health Guideline of 0.1 ppb for the group of five haloacetic acids, or HAA5, was defined in a peer-reviewed scientific study by EWG and represents a one-in-a-million lifetime cancer risk level. This health guideline protects against cancer.

Pollution Sources

Treatment Byproducts

Filtering Options

Activated Carbon

Reverse Osmosis

Haloacetic acids (HAA9)†

Potential Effect: cancer261x EWG'S HEALTH GUIDELINE
THIS UTILITY15.7 ppb
EWG HEALTH GUIDELINE0.06 ppb
NO LEGAL LIMIT
DETAILS
X

Haloacetic acids (HAA9)

more about
this contaminant

Haloacetic acids are formed when disinfectants such as chlorine are added to tap water. The group of nine haloacetic acids includes monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid and dibromoacetic acid, which are regulated as a group by the federal government (HAA5); and bromochloroacetic acid, bromodichloroacetic acid, chlorodibromoacetic acid, and tribromoacetic acid.

Haloacetic acids (HAA9) was found at 261 times above EWG's Health Guideline.

EWG Health Guideline

0.06 ppb or less

This Utility

15.7 ppb

National Average

23.7 ppb

State Average

16.1 ppb
NO LEGAL LIMIT
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2017-2021.
ppb = parts per billion

Health Risks

The EWG Health Guideline of 0.06 ppb for the group of nine haloacetic acids, or HAA9, was defined in a peer-reviewed scientific study by EWG and represents a one-in-a-million lifetime cancer risk level as . This health guideline protects against cancer.

Pollution Sources

Treatment Byproducts

Filtering Options

Activated Carbon

Reverse Osmosis

Nitrate

Potential Effect: cancer2.1x EWG'S HEALTH GUIDELINE
THIS UTILITY0.292 ppm
EWG HEALTH GUIDELINE0.14 ppm
LEGAL LIMIT10 ppm
DETAILS
X

Nitrate, a fertilizer chemical, frequently contaminates drinking water due to agricultural and urban runoff, and discharges from municipal wastewater treatment plants and septic tanks. Excessive nitrate in water can cause oxygen deprivation in infants and increase the risk of cancer. Click here to read more about nitrate.

Nitrate was found at 2.1 times above EWG's Health Guideline.

EWG Health Guideline

0.14 ppm or less

This Utility

0.292 ppm

Legal Limit

10 ppm

National Average

0.935 ppm

State Average

0.421 ppm
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2017-2019.
ppm = parts per million

Health Risks

The EWG Health Guideline of 0.14 ppm for nitrate was defined by EWG . This health guideline protects against cancer and harm to fetal growth and development.

Pollution Sources

Agriculture

Runoff & Sprawl

Naturally Occurring

Filtering Options

Reverse Osmosis

Ion Exchange

Perfluoroheptanoic acid (PFHPA)

Potential Effect: 2.4x EWG'S HEALTH GUIDELINE
THIS UTILITY2.44 ppt
EWG HEALTH GUIDELINE1 ppt
NO LEGAL LIMIT
DETAILS
X

Perfluoroheptanoic acid (PFHPA)

more about
this contaminant

Perfluoroheptanoic acid is a member of a group of perfluorinated chemicals used in many consumer products. Perfluorinated chemicals can cause serious health effects, including cancer, endocrine disruption, accelerated puberty, liver and immune system damage, and thyroid changes. These chemicals are persistent in the environment and they accumulate in people. Click here to read more about perfluorinated chemicals.

Perfluoroheptanoic acid (PFHPA) was found at 2.4 times above EWG's Health Guideline.

EWG Health Guideline

1 ppt or less

This Utility

2.44 ppt

National Average

0.215 ppt

State Average

0.491 ppt
NO LEGAL LIMIT
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2013-2019.
ppt = parts per trillion

Health Risks

The EWG Health Guideline of 1 ppt for perfluoroheptanoic acid was defined by EWG based on studies by Phillipe Grandjean of Harvard University and many other independent researchers who found reduced effectiveness of vaccines and adverse impacts on mammary gland development from exposure to PFOA and PFOS, the two PFAS most widely detected in drinking water. This health guideline applies to the entire class of PFAS detected in water.

Pollution Sources

Industry

Runoff & Sprawl

Filtering Options

Activated Carbon

Reverse Osmosis

Perfluorooctanoic acid (PFOA)

Potential Effect: cancer3,244x EWG'S HEALTH GUIDELINE
THIS UTILITY22.7 ppt
EWG HEALTH GUIDELINE0.007 ppt
PROPOSED LEGAL LIMIT4 ppt
DETAILS
X

Perfluorooctanoic acid (PFOA)

more about
this contaminant

Perfluorooctanoic acid (PFOA) is a member of a group of perfluorinated chemicals used in many consumer products. PFOA and other perfluorinated chemicals can cause serious health effects, including cancer, endocrine disruption, accelerated puberty, liver and immune system damage, and thyroid changes. These chemicals are persistent in the environment and they accumulate in people. Click here to read more about perfluorinated chemicals.

Perfluorooctanoic acid (PFOA) was found at 3,244 times above EWG's Health Guideline.

EWG Health Guideline

0.007 ppt or less

This Utility

22.7 ppt

Proposed Legal Limit

4 ppt

National Average

1.15 ppt

State Average

3.2 ppt
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2013-2019.
ppt = parts per trillion

Health Risks

The EWG Health Guideline of 0.007 ppt for PFOA was proposed by California Office of Environmental Health Hazard Assessment as a public health goal, the level of a drinking water contaminant that does not pose a significant health risk. This health guideline protects against cancer.

Pollution Sources

Industry

Runoff & Sprawl

Filtering Options

Activated Carbon

Reverse Osmosis

Total trihalomethanes (TTHMs)†

Potential Effect: cancer75x EWG'S HEALTH GUIDELINE
THIS UTILITY11.3 ppb
EWG HEALTH GUIDELINE0.15 ppb
LEGAL LIMIT80 ppb
DETAILS
X

Total trihalomethanes (TTHMs)

more about
this contaminant

Trihalomethanes are cancer-causing contaminants that form during water treatment with chlorine and other disinfectants. The total trihalomethanes group includes four chemicals: chloroform, bromodichloromethane, dibromochloromethane and bromoform.

Total trihalomethanes (TTHMs) was found at 75 times above EWG's Health Guideline.

EWG Health Guideline

0.15 ppb or less

This Utility

11.3 ppb

Legal Limit

80 ppb

National Average

29.7 ppb

State Average

18 ppb
The state and national averages were calculated using the averages of the contaminant measurements for each utility in 2017-2019.
ppb = parts per billion

Health Risks

The health guideline of 0.15 parts per billion, or ppb, for the group of four trihalomethanes, or THM4/TTHM, was defined in a peer-reviewed scientific study by EWG and represents a one-in-one-million lifetime cancer risk level.

Pollution Sources

Treatment Byproducts

Filtering Options

Activated Carbon

Reverse Osmosis

Includes chemicals detected in 2017-2019 for which annual utility averages exceeded an EWG-selected health guideline established by a federal or state public health authority; chemicals detected under the EPA's Unregulated Contaminant Monitoring Rule (UCMR 3) program in 2013 to 2015 (and subsequent testing when available), for which annual utility averages exceeded a health guideline established by a federal or state public health authority; chemicals detected under the EPA's Unregulated Contaminant Monitoring Rule (UCMR 4) program in 2017 to 2020 (and subsequent testing when available), for which annual utility averages exceeded a health guideline established by a federal or state public health authority.

† HAA5 is a contaminant group that includes monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, monobromoacetic acid and dibromoacetic acid. HAA9 is a contaminant group that includes the chemicals in HAA5 and bromochloroacetic acid, bromodichloroacetic acid, chlorodibromoacetic acid and tribromoacetic acid. TTHM is a contaminant group that includes bromodichloromethane, bromoform, chloroform and dibromochloromethane.


Other Contaminants Tested


Chemicals tested for but not detected from 2014 to 2019:

1,1,1,2-Tetrachloroethane , 1,1,1-Trichloroethane , 1,1,2,2-Tetrachloroethane , 1,1,2-Trichloroethane , 1,1-Dichloroethane , 1,1-Dichloroethylene , 1,1-Dichloropropene , 1,2,3-Trichlorobenzene , 1,2,3-Trichloropropane , 1,2,4-Trichlorobenzene , 1,2,4-Trimethylbenzene , 1,2-Dibromo-3-chloropropane (DBCP) , 1,2-Dichloroethane , 1,2-Dichloropropane , 1,3,5-Trimethylbenzene , 1,3-Butadiene , 1,3-Dichloropropane , 1,4-Dioxane , 1-butanol , 10:2 Fluorotelomer sulfonic acid (10:2 FTSA) , 2,2-Dichloropropane , 2,4,5-TP (Silvex) , 2,4-D , 2-methoxyethanol , 2-propen-1-ol , 3-Hydroxycarbofuran , 4:2 Fluorotelomer Sulfonic Acid (4:2 FTSA) , 8:2 Fluorotelomer Sulfonic Acid (8:2 FTSA) , Alachlor (Lasso) , Aldicarb , Aldicarb sulfone , Aldicarb sulfoxide , Aldrin , Alpha-hexachlorocyclohexane , Antimony , Arsenic , Atrazine , Baygon (Propoxur) , Benzene , Benzo[a]pyrene , Beryllium , Bromobenzene , Bromochloromethane , Bromomethane , Butachlor , Butylated hydroxyanisole , Cadmium , Carbaryl , Carbofuran , Carbon tetrachloride , Chlordane , Chlorodifluoromethane , Chloroethane , Chloromethane , Chlorpyriphos , cis-1,2-Dichloroethylene , cis-1,3-Dichloropropene , Combined uranium , Cyanide , Dalapon , Di(2-ethylhexyl) adipate , Di(2-ethylhexyl) phthalate , Dibromomethane , Dicamba , Dichlorodifluoromethane , Dichloromethane (methylene chloride) , Dieldrin , Dimethipin , Dinoseb , Diquat , Endrin , Ethoprop , Ethylbenzene , Ethylene dibromide , Fluoride , Germanium , Glyphosate , Heptachlor , Heptachlor epoxide , Hexachlorobenzene (HCB) , Hexachlorobutadiene , Hexachlorocyclopentadiene , Isopropylbenzene , Lindane , m-Dichlorobenzene , Mercury (inorganic) , Methiocarb , Methomyl , Methoxychlor , Metolachlor , Metribuzin , Molybdenum , Monochlorobenzene (chlorobenzene) , MTBE , n-Butylbenzene , N-Ethyl perfluorooctane sulfonamide (N-EtFOSE) , N-ethyl perfluorooctane sulfonamido acetic acid (N, N-Ethyl Perfluorooctanesulfonamido Ethanol (EtFOSE, N-Methyl Perfluorooctane Sulfonamide (NMeFOSA) , N-Methyl Perfluorooctanesulfonamido Ethanol (NMeFO, N-methyl perfluorooctanesulfonamidoacetic acid , n-Propylbenzene , Naphthalene , Nitrite , o-Chlorotoluene , o-Dichlorobenzene , o-toluidine , Oxamyl (Vydate) , Oxyflurofen , p-Chlorotoluene , p-Dichlorobenzene , p-Isopropyltoluene , Pentachlorophenol , Perfluorodecane Sulfonic Acid (PFDoS) , Perfluorodecanesulfonic acid (PFDS) , Perfluorodecanoic acid (PFDA) , Perfluorododecanoic acid (PFDoA) , Perfluoroheptane sulfonic acid (PFHpS) , Perfluorohexadecanoic acid (PFHxDA) , Perfluorononanesulfonic acid (PFNS) , Perfluorooctadecanoic acid (PFODA) , Perfluorotetradecanoic acid (PFTA) , Perfluorotridecanoic acid (PFTrDA) , Permethrin , Picloram , Profenofos , Propachlor , Quinoline , Radium, combined (-226 & -228) , sec-Butylbenzene , Selenium , Silver , Simazine , Styrene , Tebuconazole , tert-Butylbenzene , Tetrachloroethylene (perchloroethylene) , Thallium , Toluene , Toxaphene , trans-1,2-Dichloroethylene , trans-1,3-Dichloropropene , Tribufos , Trichloroethylene , Trichlorofluoromethane , Vinyl chloride , Xylenes (total)

Merrimack Village District compliance with legally mandated federal standards:

  • From April 2019 to March 2021, Merrimack Village District complied with health-based drinking water standards.
  • 1 QUARTER
    in violation of any federal drinking water standard from April 2019 to March 2021

Information in this section on Merrimack Village District comes from the U.S. EPA Enforcement and Compliance History Online database (ECHO).

LEARN MORE ABOUT THIS UTILITY

Water Filters That Can Reduce Contaminant Levels

ContaminantActivated Carbonactivated carbonReverse Osmosisreverse osmosisIon Exchangeion exchange
CONTAMINANTS ABOVE
HEALTH GUIDELINES
Bromodichloromethane
Chloroform
Chromium (hexavalent)
Dibromochloromethane
Haloacetic acids (HAA5)
Haloacetic acids (HAA9)
Nitrate
Perfluoroheptanoic acid (PFHPA)
Perfluorooctanoic acid (PFOA)
Total trihalomethanes (TTHMs)
OTHER CONTAMINANTS
DETECTED
6:2 Fluorotelomer Sulfonic Acid (6:2 FTSA)
Barium
Bromoform
Chlorate
Chromium (total)
Cobalt
Manganese
Perfluorobutane sulfonate (PFBS)
Perfluorobutanoic acid (PFBA)
Perfluoroheptanoic acid (PFHpA)
Perfluorohexane sulfonate (PFHXS)
Perfluorohexanoic Acid (PFHxA)
Perfluorononanoic acid (PFNA)
Perfluorooctane sulfonate (PFOS)
Perfluorooctanesulfonamide (PFOSA)
Perfluoropentane sulfonic acid (PFPeS)
Perfluoropentanoic acid (PFPeA)
Perfluoroundecanoic acid (PFUnA)
Strontium
Vanadium

Take Action

Contact Your Local Official

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LEARN MORE

Filter Out Contaminants

Check out our recommendations for filters to protect your water against the detected contaminants.

EWG’S WATER FILTER GUIDE