Layer 1

Is Somerville Tap Water Safe to Drink?

Yes! Generally Safe to Drink*

LAST UPDATED: 7:47 pm, July 31, 2022

Table of Contents

Can You Drink Tap Water in Somerville?

Yes, Somerville's tap water is generally considered safe to drink as Somerville has no active health based violations of the Safe Drinking Water Act (SDWA) that we are aware of. Other factors such as lead piping in a home, or low levels of pollutants on immunocompromised individuals, should also be considered, however. To find more recent info we might have, you can check out our boil water notice page or the city's water provider website.

According the EPA’s ECHO database, from April 30, 2019 to June 30, 2022, Somerville's water utility, Somerville Water Dept. (Mwra), had 0 violations of the Safe Drinking Water Act. For more details on the violations, please see our violation history section below. The last violation for Somerville was resolved on Nov. 30, 2010. This assessment is based on the Somerville Water Dept. (Mwra) water system, other water systems in the city may have different results.

While tap water that meets the EPA health guidelines generally won’t make you sick to your stomach, it can still contain regulated and unregulated contaminants present in trace amounts that could potentially cause health issues over the long-run. These trace contaminants may also impact immunocompromised and vulnerable individuals.

The EPA is reviewing if it’s current regulations around pollutant levels in tap water are strict enough, and the health dangers posed by unregulated pollutants, like PFAS.

Water Quality Report for Somerville Tap Water

The most recent publicly available numbers for measured contaminant levels in Somerville tap water are in its 2020 Water Quality Report. As you can see, there are levels which the EPA considers to be acceptable, but being below the maximum allowable level doesn’t necessarily mean the water is healthy.

Lead in tap water, for example, is currently allowed at up to 15ppb by the EPA, but it has set the ideal goal for lead at zero. This highlights how meeting EPA standards doesn’t necessarily mean local tap water is healthy.

EPA regulations continue to change as it evaluates the long term impacts of chemicals and updates drinking water acceptable levels. The rules around arsenic, as well as, lead and copper are currently being re-evaluated.

There are also a number of "emerging" contaminants that are not currently. For example, PFAS (Per- and polyfluoroalkyl substances), for which the EPA has issued a health advisory. PFAS are called "forever chemicals" since they tend not to break down in the environment or the human body and can accumulate over time.

We recommend looking at the contaminants present in Somerville's water quality reports, or getting your home's tap water tested to see if you should be filtering your water.

Somerville Tap Water Safe Drinking Water Act Violation History - Prior 10 Years

Below is a ten year history of violations for the water system named Somerville Water Dept. (Mwra) for Somerville in Massachusetts. For more details please see the "What do these Violations Mean?" section below.

From Nov. 1, 2010 to Nov. 30, 2010, Somerville had 1 health-based Safe Drinking Water Act violation with the violation category being Maximum Contaminant Level Violation, more specifically, the violation code was Maximum Contaminant Level Violation, Monthly (TCR) which falls into the Microbials rule code group, and the Total Coliform Rules rule code family for the following contaminant code: Coliform (TCR).

Is there Lead in Somerville Water?

Based on the EPA’s ECHO Database, 90% of the samples taken from the Somerville water system, Somerville Water Dept. (Mwra), between sample start date and sample end date, were at or below, 0.0129 mg/L of lead in Somerville water. This is 86.0% of the 0.015 mg/L action level. This means 10% of the samples taken from Somerville contained more lead.

While Somerville water testing may have found 0.0129 mg/L of lead in its water, that does not mean your water source has the same amount. The amount of lead in water in a city can vary greatly from neighborhood to neighborhood, or even building to building. Many buildings, particularly older ones, have lead pipes or service lines which can be a source of contamination. To find out if your home has lead, we recommend getting you water tested.

No amount of lead in water is healthy, only less dangerous. As lead accumulates in our bodies over time, even exposure to relatively small amounts can have negative health effects. For more information, please check out our Lead FAQ page.

Are there PFAS in Somerville Tap Water?

Currently, testing tap water for PFAS isn’t mandated on a national level. We do have a list of military bases where there have been suspected or confirmed leaks. There appears to be at least one military base - Hanscom Air Force Base - near Somerville with suspected leaks.

With many potential sources of PFAS in tap water across the US, the best information we currently have about which cities have PFAS in their water is this ewg map, which you can check to see if Somerville has been evaluated for yet.

Our stance is better safe than sorry, and that it makes sense to try to purify the tap water just in case.

Somerville SDWA Violation History Table - Prior 10 Years

Compliance Period Status Health-Based? Category Code Code Rule Code Contaminant Code Rule Group Code Rule Family Code
11/01/2010 - 11/30/2010 Resolved Yes Maximum Contaminant Level Violation (MCL) Maximum Contaminant Level Violation, Monthly (TCR) (22) Total Coliform Rule (110) Coliform (TCR) (3100) Microbials (100) Total Coliform Rules (110)

What do these Violations Mean?

Safe Drinking Water Act Violations categories split into two groups, health based, and non-health based. Generally, health based violations are more serious, though non-health based violations can also be cause for concern.

Health Based Violations

  1. Maximum contaminant levels (MCLs) - maximum allowed contaminant level was exceeded.
  2. Maximum residual disinfectant levels (MRDLs) - maximum allowed disinfectant level was exceeded.
  3. Other violations (Other) - the exact required process to reduce the amounts of contaminants in drinking water was not followed.

Non-Health Based Violations

  1. Monitoring and reporting violations (MR, MON) - failure to conduct the required regular monitoring of drinking water quality, and/or to submit monitoring results on time.
  2. Public notice violations (Other) - failure to immediately alert consumers if there is a serious problem with their drinking water that may pose a risk to public health.
  3. Other violations (Other) - miscellaneous violations, such as failure to issue annual consumer confidence reports or maintain required records.

SDWA Table Key

Field Description
Compliance Period Dates of the compliance period.
Status Current status of the violation.
  • Resolved - The violation has at least one resolving enforcement action. In SDWIS, this indicates that either the system has returned to compliance from the violation, the rule that was violated was no longer applicable, or no further action was needed.
  • Archived - The violation is not Resolved, but is more than five years past its compliance period end date. In keeping with the Enforcement Response Policy, the violation no longer contributes to the public water system's overall compliance status. Unresolved violations are also marked as Archived when a system ceases operations (becomes inactive).
  • Addressed - The violation is not Resolved or Archived, and is addressed by one or more formal enforcement actions.
  • Unaddressed - The violation is not Resolved or Archived, and has not been addressed by formal enforcement.
show details
Health-Based? Whether the violation is health based.
Category Code
The category of violation that is reported.
  • TT - Treatment Technique Violation
  • MRDL - Maximum Residual Disinfectant Level
  • Other - Other Violation
  • MCL - Maximum Contaminant Level Violation
  • MR - Monitoring and Reporting
  • MON - Monitoring Violation
  • RPT - Reporting Violation
show details
Code A full description of violation codes can be accessed in the SDWA_REF_CODE_VALUES (CSV) table.
Contaminant Code A code value that represents a contaminant for which a public water system has incurred a violation of a primary drinking water regulation.
Rule Code Code for a National Drinking Water rule.
  • 110 - Total Coliform Rule
  • 121 - Surface Water Treatment Rule
  • 122 - Long Term 1 Enhanced Surface Water Treatment Rule
  • 123 - Long Term 2 Enhanced Surface Water Treatment Rule
  • 130 - Filter Backwash Rule
  • 140 - Ground Water Rule
  • 210 - Stage 1 Disinfectants and Disinfection Byproducts Rule
  • 220 - Stage 2 Disinfectants and Disinfection Byproducts Rule
  • 230 - Total Trihalomethanes
  • 310 - Volatile Organic Chemicals
  • 331 - Nitrates
  • 332 - Arsenic
  • 333 - Inorganic Chemicals
  • 320 - Synthetic Organic Chemicals
  • 340 - Radionuclides
  • 350 - Lead and Copper Rule
  • 410 - Public Notice Rule
  • 420 - Consumer Confidence Rule
  • 430 - Miscellaneous
  • 500 - Not Regulated
  • 111 - Revised Total Coliform Rule
show details
Rule Group Code Code that uniquely identifies a rule group.
  • 120 - Surface Water Treatment Rules
  • 130 - Filter Backwash Rule
  • 140 - Groundwater Rule
  • 210 - Stage 1 Disinfectants and Disinfection Byproducts Rule
  • 220 - Stage 2 Disinfectants and Disinfection Byproducts Rule
  • 230 - Total Trihalomethanes
  • 310 - Volatile Organic Chemicals
  • 320 - Synthetic Organic Chemicals
  • 330 - Inorganic Chemicals
  • 340 - Radionuclides
  • 350 - Lead and Copper Rule
  • 400 - Other
  • 500 - Not Regulated
  • 110 - Total Coliform Rules
  • 410 - Public Notice Rule
  • 420 - Consumer Confidence Rule
  • 430 - Miscellaneous
show details
Rule Family Code Code for rule family.
  • 100 - Microbials
  • 200 - Disinfectants and Disinfection Byproducts Rule
  • 300 - Chemicals
  • 400 - Other
  • 500 - Not Regulated
show details

For more clarification please visit the EPA's data dictionary.

Somerville Water - Frequently Asked Questions

A service line connects your building’s plumbing to the water main in your street. In some older buildings, the service line is made of lead and can add significant amounts of lead to your drinking water. Replacing the lead service line can eliminate a major source of lead in your drinking water. Contact your local water department to find out if you have a lead service line. You can also scratch the pipe entering your home near your water meter with a key. Lead pipes will show a dull grey or silver color, while copper pipes will not. For more information go to MWRA Funding to Replace Lead Service Lines MWRA and its Advisory Board offer zero -interest loans to customer communities for full lead service line replacement projects. Each MWRA community can develop its own local plan, and many communities have already taken steps to remove lead service lines. To find out more, contact your local water department. How to Test Your Drinking Water Interested in testing your home drinking water for lead? Contact your local water department about testing for lead in your drinking water. Or, go to the list of certified laboratories and sampling instructions available on the lead testing page at You may also call MWRA at 617-242-5323 for more information.
Interested in testing your home drinking water for lead? Contact your local water department about testing for lead in your drinking water. Or, go to the list of certified laboratories and sampling instructions available on the lead testing page at You may also call MWRA at 617-242-5323 for more information.
To contact customer service for the Somerville water provider, Somerville Water Dept. (Mwra), please use the information below.
Already have an account?

Existing customers can login to their Somerville Water Dept. (Mwra) account to pay their Somerville water bill by clicking here.

Want to create a new account?

If you want to pay your Somerville Water Dept. (Mwra) bill online and haven't made an account yet, you can create an account online. Please click here to create your account to pay your Somerville water bill.

Want to pay without an account?

If you don't want to make an account, or can't remember your account, you can make a one-time payment towards your Somerville water bill without creating an account using a one time payment portal with your account number and credit or debit card. Click here to make a one time payment.

Starting Your Service

Moving to a new house or apartment in Somerville means you will often need to put the water in your name with Somerville Water Dept. (Mwra). In order to put the water in your name, please click the link to the start service form below. Start service requests for water bills typically take two business days.

Start Service Form

Want to create a new account?

Leaving your house or apartment in Somerville means you will likely need to take your name off of the water bill with Somerville Water Dept. (Mwra). In order to take your name off the water bill, please click the link to the stop service form below. Stop service for water bills requests typically take two business days.

Stop Service Form

The estimated price of bottled water

$2 in USD (1.5-liter)


Somerville tap water
  • Drinking Water Pollution and Inaccessibility 20% Low
  • Water Pollution 46% Moderate
  • Drinking Water Quality and Accessibility 80% Very High
  • Water Quality 54% Moderate

The above data is comprised of subjective, user submitted opinions about the water quality and pollution in Somerville, measured on a scale from 0% (lowest) to 100% (highest).

Related FAQS

Somerville Water Quality Report (Consumer Confidence Report)

The EPA mandates that towns and cities consistently monitor and test their tap water. They must report their findings in an annual Consumer Confidence Report. Below is the most recent water quality report from Somerville's Water. If you would like to see the original version of the report, please click here.









￿￿￿￿￿ ￿￿￿￿￿￿￿￿￿￿￿￿￿￿ ￿￿ ￿ ￿￿￿￿￿￿


￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿￿ ￿￿￿


Massachusetts Water Resources Authority And Your Local Water Department

Where To Go For Further Information




Massachusetts Water Resources Authority (MWRA)


Department of Conservation and Recreation (DCR)


Massachusetts Dept. of Public Health (DPH)


Massachusetts Dept. of Environmental Protection


US Centers for Disease Control & Prevention (CDC)


List of State Certified Water Quality Testing Labs


Source Water Assessment and Protection Reports


Information on Water Conservation



Public Meetings 617-788-1117

MWRA Board of Directors

MWRA Advisory Board


Water Supply Citizens Advisory Committee


For A Larger Print Version, Call 617-242-5323.

This report is required under the Federal Safe Drinking Water Act. MWRA PWS ID# 6000000





Kathleen A. Theoharides, Chair

John J. Carroll,

Vice Chair

Andrew M. Pappastergion, Secretary

Christopher Cook

Paul E. Flanagan

Joseph C. Foti

Brian Peña

Henry F. Vitale

Patrick Walsh

John J. Walsh

Jennifer L. Wolowicz

Dear Customer,

This report brings you the results of our annual water quality testing. While 2020 was a year filled with uncertainty, one thing remained constant: the quality of your drinking water was excellent. MWRA takes hundreds of thousands of tests each year, and for 2020, we again met every federal and state drinking water standard.

As providers of essential services, the women and men of MWRA have been on the job every day during the pandemic to make sure that the customers in our service area received uninterrupted delivery of safe drinking water.

Our reservoirs have ample supplies to meet the demands of our service area. However, water is the most precious resource and we encourage everyone to save water wherever possible. You can find tips on how to conserve water on our website at

System-wide, we were again below the Lead Action Level. Lead continues to be a priority for us and our member communities. To date, 11 communities have utilized over $17 million through our zero-interest loans to remove lead service lines. Please read your community’s letter on page 7 for more information on your local water system.

PFAS, or ‘forever chemicals’ have been in the news a lot lately. As expected, given our well-protected sources, our test results easily meet the newly issued Massachusetts Department of Environmental Protection standards. No changes in our treatment are needed, and we continue to monitor this important issue.

I hope you will take a few moments to read this report. We have great confidence in the water we deliver to your homes and businesses and we want you to as well. Please contact us if you have any questions or comments about your water quality, or any of MWRA's programs.


Frederick A. Laskey

Executive Director

For more information on MWRA and its Board of Directors, visit


Ware River




































Carroll Water





Storage Tank


Plant And



Hydroelectric Generator





DCR Protected Land





Other Protected Land








Safe Drinking Water Is Essential

Safe drinking water is essential

  • to life, health, and safety. Healthcare, fire services and
    other emergency responders rely on safe, available water.
    In 2020, MWRA worked with the 53 communities receiving our drinking
    water to supply an average of 200 million gallons of
    water each day to home, business, school and hospital taps.

Essential Information About Your Water

This 2020 Water Quality Report will provide you with essential information on your drinking water-how we test, treat, and ensure the safety of your water-every day, without interruption. MWRA ensures the quality of your water through a compre- hensive protection, treatment, distribution and system-wide evaluation process that ensures the safety of the water you receive.

MWRA’s Water Sources

MWRA’s efforts to protect your drinking water start 65 miles west of Boston,

at the Quabbin Reservoir, and the Wachusett Reservoir, 35 miles west of Boston. The combined supply of these two reservoirs provided an average of 200 million gallons of high quality water every day to our consumers in 2020. The Ware River also provides additional water when needed.

The Quabbin and Wachusett watersheds —the areas that drain water into the reservoirs—are naturally protected. Over

85% of the watersheds are covered in forests and wetlands, which help filter the rain and snow as they enter the streams that flow to the reservoirs. This water comes in contact with soil, rock, plants, and other material as it follows its natural path to the reservoirs. While this process helps to clean the water, it can also dissolve and carry very small amounts of material into the reservoir. Minerals from soil and rock do not typically cause problems in the water. Water can also transport contaminants, including bacteria, viruses or other potential pathogens, from human and animal activity. Test results show few contaminants are found in the reservoir water. The few that are detected are in very small amounts that are well below EPA’s standards.

Water Source Protection

A Source Water Assessment Program report was developed by the Department of Environmental Protection (DEP), for the Quabbin and Wachusett Reservoirs. The DEP report commends the Department of Conservation and Recreation (DCR), and MWRA for our source water protection

plans, and states that our “watershed protection programs are very

successful and greatly reduce the actual risk of contamination.” MWRA and DCR follow the report recommendations to maintain the

pristine watershed areas.

Testing from Forest to Faucet

MWRA and your community work together to test your drinking water frequently, from the water’s source in the Quabbin Reservoir to your kitchen or workplace tap.

MWRA laboratories conduct hundreds of thousands of tests every year for 120 potential contaminants. You can learn more about our testing for potential waterborne contaminants on our website at The 2020 water quality tests are shown below. These results confirm the quality and safety of the water delivered each day to your community, and it tastes great right from the start.

Turbidity (or cloudiness of the water), for example, is one measure of overall water quality. All water must be below 5 NTU (Nephelometric Turbidity Units) and water can only be above 1 NTU if it does not interfere with effective disinfection. In 2020, typical levels in the Wachusett Reservoir were

0.33 NTU, with the highest level of turbidity at 0.67 NTU, well below the standard.

MWRA also tests reservoir water for pathogens such as fecal coliform bacteria, and the parasites Cryptosporidium and Giardia, that can enter the water from animal or human waste. All test results in 2020 were well within state and federal testing and treatment standards. For more information, please visit







Total Trihalomethanes

Haloacetic Acids-5


ppm ppm ppm ppm ppb ppb

(MCL) Highest









(We Found)









Range Of






4.9-23.1 ND-17.4











How It Gets In The Water


Common mineral in nature


Water disinfectant


Additive for dental health


Atmospheric deposition


Byproduct of water disinfection


Byproduct of water disinfection



KEY: MCL￿Maximum Contaminant Level. The highest level of a contaminant allowed in water. MCLs are set as close to the MCLGs as feasible using the best available technology. MCLG=Maximum Contaminant Level Goal. The level of contaminant in drinking water below which there is no known or expected risk to health. MCLGs allow for a margin of safety. MRDL=Maximum Residual Disinfectant Level. The highest level of a disinfectant allowed in drinking water. There is convincing evidence that addition of a disinfectant is necessary for control of microbial contaminants. MRDLG=Maximum Residual Disinfectant Level Goal. The level of a drinking water disinfectant below which there is no known or expected health risk. MRDLGs do not reflect the benefits of the use of disinfectants to control microbial contamination. ppm=parts per million ppb=parts per billion NS=no standard ND=non-detect ^=As required by DEP, the maximum result is reported for nitrate, not the average.




Essential Water System Protection

MWRA and DCR protect the water you drink by testing, treating and protecting water quality. From the streams in the watershed, through hundreds of miles of MWRA and thousands of miles of local pipes all the way to your home. MWRA works with the Department of Conservation and Recreation (DCR) to protect 150,000 acres of permanently protected forested land and wetlands in the watershed. DCR maintains a nationally recognized protection program that includes extensive water quality testing, stormwater controls, water quality maintenance and development regulations.

MWRA maintains a state of the art water monitoring system that operates continuously —24 hours a day, 7 days a week—before and after treatment. This system helps us confirm the water is free of contaminants, and allows MWRA to rapidly respond to any changes in water quality.

MWRA’s modern treatment processes make sure your water is safe, fresh, and tastes

FACTS ABOUT SODIUM Sodium in water contributes only a small fraction of a person’s overall sodium intake (less

than 5%). MWRA tests for sodium monthly and the highest level found was 42.7 mg/L (about 10 mg per 8 oz. glass). This level would be considered Very Low Sodium by the Food and Drug Administration (FDA).

MWRA‘s John J. Carroll

Water Treatment Plant

great. Part of the reason that the water tastes so good is MWRA’s advanced water treatment at the John J. Carroll Water Treatment Plant in Marlborough. First, your water is treated with ozone —produced by pure oxygen. Ozone disinfects the water, killing bacteria, viruses and other organisms. It also improves water clarity and makes the water taste better. Next we use ultraviolet light (UV) disinfection, further improving the quality of the water. UV light is essentially a more powerful form of the natural disinfection from sunlight, and further ensures that any pathogens in the water from our reservoirs are rendered harmless.

In addition, fluoride is added to promote dental health, and the water chemistry is adjusted to reduce corrosion of home plumbing. Last, we add monochloramine (combining chlorine and ammonia), a mild and long-lasting disinfectant to provide continuing protection of the water as it travels through miles of pipelines to your home.

Ensuring System Redundancy for Continuing Service

Our goal is to provide a continuous supply of safe, clean water to every person and

organization in the MWRA service area. Redundant pipelines and tunnels allow inspection and maintenance of key facilities while ensuring uninterrupted service. Construction of a second pipeline to provide more reliable service to communities to the south is ongoing. Construction is now underway to repair and improve the Weston Aqueduct Supply Main 3 in Weston, Waltham, Belmont, Arlington and Medford. And planning and environmental review for two new tunnels north and south of Boston that will provide redundancy for the entire region is now well underway.

Distribution System—Pipeline


MWRA continues to rehabilitate and replace pipelines throughout the distribution system to improve both reliability and water quality. MWRA also provides zero -interest loans to customer communities for local pipeline projects. In 2020, $36 million was loaned to communities to fund 24 community projects for the replacement or rehabilitation of older unlined pipes or replacement of lead service lines.




MWRA’s emergency planning and commitment to providing reliable service allowed us to keep the water and sewer systems working continuously over the past year. We activated our long-standing pandemic response plan, protected our staff with changed work rules and social distancing, and met all drinking water testing and safety requirements.




Essential Facts-Lead In Drinking Water


Why is lead in drinking water important?

Lead affects young children, and may cause damage to the brain, slow growth and development, and cause learning and behavior problems. Preventing lead exposure is particularly important if a pregnant woman or child lives in your home or apartment. Lead can also impact the health of your entire family. While lead poisoning frequently comes from exposure to lead paint dust or chips, lead in drinking water can also contribute to chronic, total lead exposure.

Lead in your home plumbing or a lead service line can contribute to elevated lead levels in the water you drink. To lower your family’s exposure to lead in drinking water, review the information on this page.

Important Lead Information From EPA

If present, elevated levels of lead can cause serious health problems, especially for pregnant women and young children. Lead in

Residential water service line connects your house to the water main which runs under your


Property Line





Water Main



drinking water comes primarily from materials and components associated with service lines and home plumbing. MWRA is responsible for providing high quality drinking water, but cannot control the variety of materials used in plumbing components. If your water has been sitting for several hours, you can minimize the potential for lead exposure by flushing your tap for 30 seconds to 2 minutes before using water for drinking or cooking. If you are concerned about lead in your water, you may wish to have your water tested. Information on lead in drinking water, testing methods, and steps you can take to minimize exposure is available from the Safe Drinking Water Hotline at 1-800-425-4791 or

How Lead Can Enter Your Water

MWRA water is lead-free when it leaves our reservoirs, and MWRA and local pipes that carry the water to your community are

made mostly of iron and steel, and don’t add lead to the water. Lead can enter your tap water through pipes in your home, your service line (the line that connects your home to the water main) if it is made of lead, lead solder used in plumbing, or from some brass fixtures.

Corrosion or wearing away of lead-based materials can add lead to tap water, especially if water sits for a long time in the pipes before it is used. MWRA’s corrosion control

Remove lead service lines to your home

Run your drinking water before using

Use a filter certified to remove lead

program helps limit the amount of lead in your water. In 1996, MWRA began adding sodium carbonate and carbon dioxide to adjust the water’s pH and buffering capacity. This treatment makes the water less corrosive and reduces leaching of lead into drinking water. Lead levels found in sample tests of tap water have dropped by about 90% since this treatment change. Learn more about lead in drinking water at

MWRA Meets Lead Standard In 2020

Under EPA rules, MWRA and your local water department must test tap water each year in a sample of homes likely to have high lead levels—those with lead solder or lead service lines. The EPA rule requires that 9 out of 10, or 90% of the sampled homes must have lead levels below the Action Level of 15 ppb in their drinking water.

All sampling rounds over the past 17 years have been below the EPA Action Level. Of the 3,482 samples taken in the last 7 years, 96.7% were below the Action Level. Results for the 450 samples taken in September 2020 are shown in the table. Nine out of ten homes were below 6.5 ppb-well below the Action Level of 15 ppb.



Target Action

Ideal Goal

#Homes Above AL/





#Homes Tested

Lead (ppb)


15 ppb



Copper (ppb)


1300 ppb








KEY: AL=Action Level - The concentration of a contaminant which, if exceeded, triggers treatment or other requirements which a water system must follow.





























40 40























Lead Action Level = 15 ppb






















































































































































































































Three communities—Boston, Medford and Melrose—were above the Lead Action Level in 2020. Your community letter on page 7 will provide you with local results and more information.

WHAT IS AN ACTION LEVEL? An Action Level is the amount of lead that requires action to reduce exposure. If your home or school’s

drinking water sample is above the Lead Action Level, additional steps to reduce the level of lead may be required. If more than 10% of your community’s samples were over the Lead Action Level (15 ppb), your local water department is taking action to address the problem. See page 7.




Ways To Reduce Lead In Your Water


Lead can enter your drinking water through pipes in your home, or your lead service line (that connects your home to the water main).

Find out how to identify and remove a lead service line if your home has one. Contact your local water department about removal options.

Do I Have a Lead Service Line?

A service line connects your building’s plumbing to the water main in your street. In some older buildings, the service line is made of lead and can add significant amounts of lead to your drinking water. Replacing the lead service line can eliminate a major source of lead in your drinking water.

Contact your local water department to find out if you have a lead service line. You can also scratch the pipe entering your home near your water meter with a key. Lead pipes will show a dull grey or silver color, while copper pipes will not. For more information go to

MWRA Funding to Replace Lead Service Lines

MWRA and its Advisory Board offer zero

-interest loans to customer communities for full lead service line replacement projects. Each MWRA community can develop its own local plan, and many communities have already taken steps to remove lead service lines. To find out more, contact your local water department.

How to Test Your Drinking Water

Interested in testing your home drinking water for lead? Contact your local water department about testing for lead in your drinking water. Or, go to the list of certified laboratories and sampling instructions available on the lead testing page at You may also call MWRA at 617-242-5323 for more information.

Free MWRA Testing for Schools and Child Care Facilities

Children consume much of their drinking water at school and daycare. The plumbing in some schools and child care facilities can contain lead, and contribute to total lead exposure. MWRA, in collaboration with MassDEP, has provided no-cost lab analysis and technical assistance for schools and child care centers across all of MWRA’s water communities since 2016. Water samples are tested at our laboratory and the results are provided to the local school, health and water departments. Since the start of this program in 2016, MWRA has completed over 38,000 tests from 506 schools across

44 communities. Results are available at: (search for “lead in schools”). Results may also be available from your local school department or water department.

Any time water has not been used for more than 6 hours, run any faucet used for drinking or cooking until after the water becomes cold.

Let the water run before using it: fresh water is better than stale. To save water, fill a pitcher with fresh water and place in the refrigerator for future use.

Never use hot water from the faucet for drinking or cooking, especially when making baby formula or other food for infants or young children.

Remove loose lead solder and debris. Every few months remove the aerator from each faucet in your home and flush the pipes for 3 to 5 minutes.

Be careful of places where you may find lead in or near your


You can identify lead service line by carefully scratching with a key. New copper service line.

home. Paint, soil, dust and pottery may contain lead. Call the Massachusetts Department of Public Health (MDPH) at 1-800-532-9571 or

1-800-424-LEAD for information on health and lead.




Essential Information On Your Water

Partners In Testing For Bacteria

MWRA and local water departments test 300 to 500 water samples each week for total coliform bacteria. Total coliform bacteria can come from the intestines of warm-blooded animals, or can be found in soil, plants, or other places. Most of the time, they are not harmful. However, their presence could signal that harmful bacteria from fecal waste may be there as well. If total coliform is detected in more than 5% of samples in a month, the water system is required to investigate the possible source and fix any identified

problems. If a water sample does test positive, we run more specific tests for E. coli, which is a bacteria found in human and animal fecal waste and may cause illness. If your community was required to do an investigation, or found E. coli, it will be in the letter from your community on page 7.

Monitoring Water For PFAS

PFAS compounds, used since the 1950s for everything from stain and water proofing to firefighting, continue to be an environmental concern. In 2020, the Department of Environmental Protection (MassDEP) published a drinking water standard for PFAS. Tests of MWRA water showed only trace amounts of these compounds, well below the new state maximum contaminant

MWRA Wins the MassDEP

Public Water Systems Award

The Department of Environmental Protection awarded a Public Water System Award to MWRA in 2020,

recognizing MWRA’s continued excellent level of performance and compliance with all drinking water standards.


ESSENTIAL TOO! MWRA takes customer concerns seriously. Every call is investigated. Most complaints

are related to discolored water (usually related to local construction or hydrant use), or conditions in a building’s plumbing. If you have any questions or concerns, contact your local water department, or call MWRA at (617) 242-5323.

level (MCL) of 20 parts per trillion. See

Important Research For New Regulations

MWRA works with EPA and health research organizations to help define new national drinking water standards by collecting data on water contaminants that are not yet regulated. With our well-protected sources, very few of these potential contaminants are found in MWRA water. Information on this testing, as well as other water quality data, including information on PFAS,

disinfection byproducts, Giardia and Cryptosporidium, and other

contaminants can be found at

Contaminants in Bottled Water and Tap Water

Drinking water, including bottled water, may reasonably be expected to

contain at least small amounts of some contaminants. The presence of contami- nants does not necessarily indicate that water poses a health risk. More information about contaminants and potential health effects can be obtained by calling the EPA’s Safe Drinking Water Hotline (1-800-426-4791) or MWRA. In order to ensure that tap water is safe to drink, the Massachusetts DEP and EPA prescribe regulations which limit the amount of certain contaminants in water provided by public water systems. U.S. Food and Drug Administration (FDA) and the Massachuset- ts Department of Public Health (MDPH) regulations establish limits for contami- nants in bottled water, which must provide the same protection for public health.

Important Health Information: Drinking Water and People with Weakened Immune Systems

Some people may be more vulnerable to contaminants in drinking water than the general population. Immuno-compromi- sed persons such as persons with cancer undergoing chemotherapy, persons who have undergone organ transplants, people with HIV/AIDS or other immune system disorders, some elderly, and infants, can be particularly at risk from infections. These people should seek advice about drinking water from their health care providers. EPA/CDC guidelines on approp- riate means to lessen the risk of infection by Cryptosporidium and other microbial contaminants are available from the EPA’s Safe Drinking Water Hotline (1-800-426-4791).


Some parts of the state are experiencing drought conditions. Although the Quabbin Reservoir is well within the “Normal” operating range for this time of year, MWRA urges its customers to conserve water wherever possible. Our website has many tips on how to save water both indoors and outdoors. Every drop counts!


A cross-connection is any temporary or permanent connection between a potable (drinking) water source and a non-potable source. Non-potable water or other sources can contaminate your drinking water if backflow occurs. Sources could include:

  • Garden hoses
  • Boilers
  • Swimming pools
  • Irrigation systems or wells
  • Residential fire protection systems

Massachusetts DEP recommends the installation of backflow prevention devices for inside and outside hose connections to help protect the water in your home as well as the drinking water system in your town. For more information on cross connections, please call 617-242-5323 or visit


The City of Somerville, Massachusetts

Public Water Supply

Department of Public Works

# 3274000

Joseph A. Curtatone


Chad A Whiting

Director Water and Sewer

The City of Somerville Water Department, in conjunction with the MWRA, is pleased to provide this annual newsletter to inform all Somerville residents about our water distribution system and water quality. We are happy to report that our drinking water meets all federal and state requirements set forth by the Safe Drinking Water Act. By continuing to comply with these strict regulations ljȶɭɢʠŹȍǫƃˁŔʋơɭɽˊɽʋơȟɽ࡫ʋǠơòȶȟơɭʽǫȍȍơĭŔʋơɭ7ơɢŔɭʋȟơȥʋƃŔȥŹơƃȶȥ˪ƎơȥʋʋǠŔʋȶʠɭƎɭǫȥȇǫȥnjˁŔʋơɭǫɽɽŔljơ

The City purchases treated water from the MWRA. The water is delivered through seven MWRA master meters into the City’s distribution system. The system consists of pipes, valves, hydrants, and service lines, which deliver the water to homes, businesses, ŔȥƎȶʋǠơɭljŔƃǫȍǫʋǫơɽljȶɭƎɭǫȥȇǫȥnjŔȥƎȶʋǠơɭʠɽơɽɽʠƃǠŔɽ˪ɭơɢɭȶʋơƃʋǫȶȥ

Somerville’s distribution system consists of approximately 125 miles of water mains ranging from four to twenty inches in diameter, much of which was installed in the late 1800s to early 1900s. To maintain and protect the system the Water Department exercises njŔʋơʽŔȍʽơɽ࡫˫ʠɽǠơɽˁŔʋơɭȟŔǫȥɽʠʋǫȍǫ˖ǫȥnj˪ɭơǠˊƎɭŔȥʋɽ࡫ȟŔǫȥʋŔǫȥɽŔȥƎɭơɢȍŔƃơɽ˪ɭơǠˊƎɭŔȥʋɽ࡫ȶʽơɭɽơơɽƃȶȥɽʋɭʠƃʋǫȶȥɢɭȶǿơƃʋɽɽʠƃǠ as rehabilitation and replacement of older unlined water mains, service line repair and installations, and a coordinates a com- ɢɭơǠơȥɽǫʽơƃɭȶɽɽƃȶȥȥơƃʋǫȶȥƃȶȥʋɭȶȍɢɭȶnjɭŔȟࡲþǠơĭŔʋơɭ7ơɢŔɭʋȟơȥʋˁǫʋǠŔɽɽǫɽʋŔȥƃơljɭȶȟȶʠɭȶȥƃŔȍȍƃȶȥʋɭŔƃʋȶɭɭơɢȍŔƃơƎࠅࠁ˪ɭơ hydrants, replaced 25 gate valves, and exercised 194 gate valves to improve system reliability. The Washington St. water main rehabilitation and replacement project was completed in 2020, which included lining 1730 linear feet, and replacing 1640 linear ljơơʋȶljˁŔʋơɭȟŔǫȥࡲ7ʠɭǫȥnjࠁ߿ࠁ߿ˁŔʋơɭȟŔǫȥ˫ʠɽǠǫȥnjˁŔɽɢʠʋȶȥǠȶȍƎƎʠơʋȶʋǠơ-¶Īz7࢚ࠀࠈɢŔȥƎơȟǫƃࡲĭơȥȶˁǠŔʽơŔŹơʋʋơɭ understanding how to protect our staff and the public from spreading the virus and look forward to a productive 2021.

þǠơ-ǫʋˊȶljòȶȟơɭʽǫȍȍơȟȶȥǫʋȶɭɽʋǠơƎɭǫȥȇǫȥnjˁŔʋơɭljȶɭɽɢơƃǫ˪ƃƃȶȥʋŔȟǫȥŔȥʋɽȶljƃȶȥƃơɭȥȶȥŔɭơnjʠȍŔɭŹŔɽǫɽࡲĭơŔɭơƃȶȍȍơƃʋǫȥnj ˁơơȇȍˊɽŔȟɢȍơɽŔʋࠁࠀƎǫljljơɭơȥʋȍȶƃŔʋǫȶȥɽʋǠɭȶʠnjǠȶʠʋʋǠơƎǫɽʋɭǫŹʠʋǫȶȥɽˊɽʋơȟࡲþǠơɽŔȟɢȍơɽŔɭơŔȥŔȍˊ˖ơƎljȶɭʋơȟɢơɭŔʋʠɭơ࡫ƃǠȍȶɭǫȥơ residual, and the presence of total coliform bacteria and E. coli. A total of 1,051 samples were collected, and we are pleased to report that there were no violations.

All public water suppliers are required by the EPA to regularly test for lead and copper. As part of the sampling program Somerville tests water taps in 15 houses and 2 schools from a DEP approved list of locations. The 2020 lead sampling test results demonstrated that 9 out of 10 homes were below the lead action level (15 ppb) at 8.87 ppb in the Spring and 14.9 ppb in the Fall. Copper levels were at 89.4 ppb, well below the Action Level of 1300 ppb.

We continue to focus on removing lead services from the system to improve water quality. Twelve lead service lines were removed through routine maintenance and upgrades in 2020. The City has also taken advantage on the “Lead Service Replacement Program” ȶljljơɭơƎŹˊ¡ĭèࡲþǠơ˪ɭɽʋƃȶȥʋɭŔƃʋˁŔɽŔˁŔɭƎơƎŹʠʋǠŔƎʋȶŹơɢʠʋȶȥǠȶȍƎƎʠơʋȶʋǠơ-¶Īz7࢚ࠀࠈɢŔȥƎơȟǫƃࡲþǠơ-ǫʋˊǫɽȍȶȶȇǫȥnj forward to aggressively moving forward with this program in April 2021.

The City of Somerville’s Water Department continues to focus on providing outstanding water quality and service reliability. Should you have questions or concerns about whether you have a lead service line or have a question about the City’s water distribution system, the Water Department is available to help. To report a problem please use the Somerville 311 system. For general inquiries or to learn about public meetings you can call us at 617-625- 6600, ext. 5850, email us at, or you can also visit the Water Department web page at



Somerville Water Department (MWRA)

EWG's drinking water quality report shows results of tests conducted by the water utility and provided to the Environmental Working Group by the Massachusetts Department of Environmental Protection, 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 2019 - March 2019), tap water provided by this water utility was in compliance with federal health-based drinking water standards.

Utility details

  • Serves: 75754
  • Data available: 2012-2017
  • Data Source: Purchased surface water
  • Total: 18

Contaminants That Exceed Guidelines

  • Bromodichloromethane*
  • Chloroform*
  • Dibromochloromethane*
  • Dichloroacetic acid*
  • Radium%2C combined (-226 & -228)*
  • Total trihalomethanes (TTHMs)*

Other Detected Contaminants

  • Aluminum*
  • Barium*
  • Bromide*
  • Chlorate
  • Chromium (hexavalent)
  • Fluoride*
  • Haloacetic acids (HAA5)*
  • Manganese*
  • Monochloroacetic acid*
  • Nitrate*
  • Strontium
  • Trichloroacetic acid*


Always take extra precautions, the water may be safe to drink when it leaves the sewage treatment plant but it may pick up pollutants during its way to your tap. We advise that you ask locals or hotel staff about the water quality. Also, note that different cities have different water mineral contents.

Sources and Resources

Layer 1
Layer 1
Layer 1
Layer 1