Overview of Lead in Massachusetts Drinking Water

Frequently asked questions about lead in drinking water and the Lead and Copper Rule

In order to help protect the public, in 1991 EPA published a regulation to control lead and copper in drinking water. This regulation is known as the Lead and Copper Rule (also referred to as the LCR). Massachusetts DEP has been given primacy to oversee and the implement federal Safe Drinking Water Act requirements, including the LCR.  Below are some frequently asked questions about the applicable requirements and the actions that are being taken here in Massachusetts.


Where does lead in drinking water come from and why is it a problem?

  • Lead primarily enters drinking water through plumbing materials and service lines.  Source waters are rarely the case of elevated lead levels in finished drinking water.
  • Corrosive (e.g., low pH or acidic) water can result in the leaching of lead from service lines and plumbing materials into drinking water.
  • Over-exposure to lead may cause health problems ranging from stomach distress to brain damage.

What is the Lead and Copper Rule?

  • The LCR is a federal regulation implemented by the U.S. EPA and State environmental agencies (MassDEP).
  • LCR is designed to minimize the ingestion of lead and copper through drinking water by reducing the corrosiveness of finished water.
  • LCR applies to all Community and Non-Transient Non-Community Water Systems (CWS and NTNCWS) statewide (approximately 800 systems in Massachusetts).
  • There is no maximum contaminant level (MCL) for lead. However, the LCR does establish an Action Level and a corrosion control Treatment Technique for both lead and copper.
  • The Action Level for lead is 0.015 milligrams per liter (mg/L), a.k.a. 15 parts per billion (ppb).
  • The Action Level is compared to the 90th percentile value of all sampling results collected during each monitoring period.  (Meaning, that if more than 10 out of 100 samples taken exceed 15 ppb, then the Action Level is triggered.)
  • Exceeding the Action Level is not a violation.
  • If the 90th percentile value exceeds the lead action level, additional actions are required; these are described in more detail below:
    • Collection of additional water quality data, including a sample of the source water
    • Conduct public education
    • Evaluate corrosion control treatment and install it if needed. If corrosion control treatment was in place at time of exceedance, commence lead line replacements

How is the LCR Implemented in Massachusetts?

  • CWS and NTNCWS public water systems (PWSs) work with MassDEP to develop a sampling plan. This sampling plan is based on an evaluation of materials used in the distribution system and service lines. This sampling plan identifies service locations (single and multi-family residences) that are most likely to have high levels of lead due to the presence of lead service lines, lead interior plumbing, or copper pipes with lead solder.
  • The number of samples that need to be collected depends on the population served. For example, a PWS that serves less than 100 people must collect 5 samples, whereas a PWS that serves over 100,000 people must collect 100 samples.
  • The PWS asks homeowners/occupants to volunteer to collect water samples from the taps at the identified service locations (taps must be used regularly, such as kitchen taps); these samples must be analyzed by a state-certified laboratory.
  • PWSs must provide all owners and/or occupants of homes and buildings sampled for lead with the sample results (whether they are above or below the action level).
  • Initially, PWSs must collect one set of samples during two consecutive six month periods. If the PWS does not exceed the lead or copper Action Levels during those two six-month periods, the PWS is eligible for annual monitoring (rather than semi-annual). PWSs on annual monitoring can apply for a waiver to go to a three-year monitoring schedule if they have three annual monitoring periods without exceeding the lead or copper Action Level.
  • What happens if the Action Level is exceeded?

    • The PWS must go back to semi-annual monitoring until the 90th percentile results are below the Action Level for two consecutive six-month periods.
    • The PWS must take all applicable follow-up actions:
      • Collect additional water quality parameters (pH, alkalinity, calcium, conductivity, orthophosphate, silica, and temperature) during the monitoring period in which the lead action level was exceeded (if the PWS is not already collecting this information). These parameters can help to determine if corrosion control treatment is operating properly or to develop an optimal corrosion control treatment if one isn’t currently in place.
      • Submit an optimal corrosion control treatment recommendation to the state if the PWS has not already done so (systems serving more than 50,000 customers have all submitted these recommendations).
      • Collect a source water lead sample to determine if the source water is contributing to the elevated lead levels.
      • Conduct public education to inform all consumers about steps that the PWS has taken, steps that the consumer should take to protect their health, and to let the consumer know that they may have to replace lead service lines under their control.
      • If the PWS has corrosion control in place and has still exceeded the lead action level, the PWS must update its material evaluation to identify all lead service lines and goosenecks and replace 7 percent of these service lines within 12 months of the exceedance, and continue this practice until monitoring results no longer exceed the lead action level.
  • When is a PWS that Exceeds the Action Level in Compliance with LCR?

    • When the lead Action Level has been exceeded, if the PWS fulfills all required follow-up actions listed above within the timelines laid out in the Rule, then the PWS remains in compliance with the Rule.
  • When is a PWS that Exceeds the Action Level Out of Compliance with LCR?

    • If the PWS fails to take any of the required follow-up actions listed above, the PWS has violated the Rule and enforcement actions are initiated.

What Additional Measures are Taken in Massachusetts to Protect the Public from Ingesting Lead through Drinking Water?

  • The Lead Contamination Control Act (LCCA)

    • Established under the federal Safe Drinking Water Act in 1988 to reduce lead in the drinking water of schools and childcare facilities.
    • All schools (K‐12) and Early Education and Care Programs facilities are covered under the LCCA.
    • MassDEP is responsible for managing the LCCA in Massachusetts. Partners include MA Department of Public Health (DPH), MA Department of Elementary and Secondary Education (ESE), MA Department of Early Education and Care (EEC) and the United States Environmental Protection Agency (U.S. EPA).
    • MassDEP provides educational information and assistance to Early Education and Care Program and K-12 facilities covered by the LCCA. Every five years, MassDEP requests updated information from these facility administrators about lead and copper monitoring and remediation efforts at their facilities.
    • Providing this information to MassDEP is voluntary. This updated information is used to provide additional training and technical assistance opportunities.
  • Additional Measures for Schools and Early Education and Child Care Programs

    • All Community Water Systems are required by Massachusetts Drinking Water Regulations to collect lead and copper samples from at least two Schools or Early Education and Care Program facilities that they serve in each sampling period, when they collect their LCR samples.
    • Early Education and Care Programs facilities with routine plumbing changes are encouraged to collect and analyze additional samples to complete an evaluation of all taps within their facility at least once every three years.
  • MassDEP’s Relationship with the Massachusetts Department of Public Health (DPH)

    • MassDEP works closely with DPH’s Bureau of Environmental Health (BEH)
    • BEH oversees the Massachusetts program that requires lead screens for all children between the ages of 9 and 12 months and again at between 2 and 3 years for their blood lead levels. In high risk communities, children are tested again at age 4.
    • A summary of these results is publicly available.
  • MassDEP’s Relationship with the U.S. Environmental Protection Agency (EPA) Region 1

    • MassDEP works very closely with EPA Region 1 on implementation of the Safe Drinking Water Act, including implementation of LCR. This includes routine reporting of LCR data to EPA.
    • EPA Region 1 is working closely with the New England States to gather additional information from the states and to provide additional assistance and guidance.




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