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Tier 1 Public Notice: Bacteriological Situation or Violation

When bacteria are detected in drinking water there are requirements for public water suppliers to notify the public.

Bacteriological situations or violations that require a Tier 1 public notice include:

  • Acute violations of the Total Coliform Rule in the distribution system (i.e., whenever an E. coli-positive repeat sample is detected, or a total coliform-positive repeat sample follows an E. coli-positive routine sample).
  • Fecal indicator positive detections under the Ground Water Rule (E.coli or Enterococci) in the source water.
  • Repeated non-acute bacteria violations or severe violation of the Total Coliform Rule (i.e., widespread total coliform in the distribution system) due to a specific incident or potential source, treatment, storage, cross-connection or other condition, as determined by MassDEP on a case-by-case basis.
  • Waterborne disease outbreak, interruption or equipment failure in treatment or supply, loss of system pressure (i.e., water outage or main break) or use of an unapproved source, as determined by MassDEP on a case-by-case basis.

Tier 1 Situations

Immediately and no later than 24 hours of your knowledge of a Tier 1 situation or violation, you are required to notify and consult with MassDEP, implement your emergency response plan, and provide public notification to consumers.

24-Hour Notification

You must contact and consult with MassDEP by the end of the day that your system has been notified of a positive E.coli or Enterococci result either in the distribution system or at the source.

  • If notification is received after MassDEP is closed, notification may be performed the next business day or by calling the MassDEP 24 hour emergency response phone number at 888-304-1133.
  • In no circumstance shall notification be performed more than 24 hours after receiving notification from the laboratory.

Consult with MassDEP

You must consult with (i.e., speak with) MassDEP Drinking Water Program staff. Voice or electronic messages do not meet consultation requirements.

  • Tier 1 bacteriological situations or violations may require either Boil or Non-Boil public notice, depending upon the specific situation and MassDEP determination.
  • You must provide public notification as soon as practical but within 24 hours after you learn of the violation/situation, even if you are unable to contact anyone at MassDEP.

Initiate Your Emergency Response Plan

Immediately begin to implement your Emergency Response Plan in accordance with 310 CMR 22.04(13) and take appropriate corrective action to resolve the situation as may be directed by MassDEP.

  • You should notify local officials of the violation/situation including your local board of health, chief municipal officer(s), and other emergency personnel, as appropriate.
  • Consecutive systems and/or interconnections - wholesale (or selling) systems and consecutive (or purchasing systems) are required to notify each other of Tier 1 situations within 24 hours and provide public notice to consumers as applicable. A consecutive system is responsible for providing public notice to the persons it serves.

Bulk Water Delivery

In the event of an emergency, your public water system may need to provide an alternative potable water source such as bottled water or bulk water delivery. A public water system that plans to use trucked (bulk) water in response to an emergency shall first contact the appropriate MassDEP regional office. In some cases, an emergency declaration may be necessary.

Only a drinking water supply source that has been approved by MassDEP shall be used as a source to fill tank trucks or trailers during water hauling operations. MassDEP recommends that someone with water treatment expertise be responsible for the operation and management of trucked potable water for use in emergencies. All transported water must carry a free chlorine residual of at least 1 ppm at the beginning of the haul and at least 0.2 ppm free chlorine residual at the end of the haul. The water supplier is responsible for documenting and keeping proper records of the emergency trucked water operation.

List of Emergency Bulk Water Providers

Procedures for Emergency Tank Truck Bulk Water Hauling

Drinking Water Policy 92-07: Bulk Water Suppliers - Sampling Requirements and Transport Responsibility

Public Notification Requirements

24-Hour Public Notice

You must issue Tier 1 public notification as soon as practical and within 24 hours after you learn of the violation and comply with any additional public notification requirements as instructed by MassDEP during consultation.

  • Tier 1 public notification is required for bacteriological related violations or situations with significant potential to have serious adverse effects on human health as a result of short-term exposure and requires immediate public notification in accordance with 310 CMR 22.16(2).


Your notice must include:

  • Population served, (make sure it is clear who is served by your water system, you may need to list the areas and consecutive water systems you may serve). Unaffected consumers (i.e., people outside of a narrow area impacted who do not need to boil their water) should be told they do not need to take action but have a right to be informed of the problem;
  • A description of the violation or situation and when the violation or situation occurred;
  • Potential adverse health effects, using required language in 310 CMR 22.16 Table 7 must be included exactly as written (presented in italics in the templates);
  • Population(s) at risk and whether alternative water supplies should be used;
  • Actions consumers should take, including when they should seek medical help, if known;
  • Source of contamination (if known);
  • What you are doing to correct the violation or situation and when you expect to return to compliance;
  • Name, business address, and phone number for additional information;
  • Required language encouraging distribution to all persons served, where applicable (presented in italics in the templates); and
  • PWS ID# and date of distribution (located at bottom of notice).

Required Language

You must include:

  • Health effects language for the specified contaminant in Table 7 of 310 CMR 22.16 in the Drinking Water Regulations, which must be included exactly as written, and is presented in italics in the templates.
  • Distribution language - The following italicized language must be included in all notices, where applicable, and is presented in italics in the templates. Use of this language does not relieve you of your obligation to take steps reasonably calculated to notify all persons served:
    Please share this information with all the other people who drink this water, especially those who may not have received this notice directly (for example, people in apartments, nursing homes, schools, and businesses). You can do this by posting this notice in a public place or distributing copies by hand or mail.

Additional Language

You may need to modify or include additional information in your notice if:

  • Your system also has elevated levels of other contaminants where boiling the water for bacteriological safety could subsequently increase levels of other contaminants such as (nitrate, nitrate, perchlorate, arsenic, synthetics, radiologicals etc.). Residents should also be aware that boiling the water would not reduce the elevated levels of other contaminants.
    Boiling the water will not reduce the level of ______ in your drinking water. If you have concerns, then it is recommended that you contact your doctor to determine what actions you should take to reduce your exposure, such as using bottled water for drinking and cooking.
  • You are a community system that does not currently add chlorine to the water.
    In response to the recent bacteria detections, we are adding sodium hypochlorite (chlorine) on a temporary basis to achieve a low chlorine residual in the water system. Low levels of chlorine and a slight discoloration may be detected in the water. Aquarium owners and users of kidney dialysis machines are advised to treat or filter the water before use.
  • You are required to provide additional precautions consumers should take when water may be contaminated with bacteria and consumers are directed to boil water prior to using.   

    Please refer to the information below and the attached notice for additional precautions you can take.
    MassDEP - Consumer Information on Boil Orders
    MassDEP - Fact Sheet: Drinking Water Contaminated with Bacteria  
    Massachusetts Department of Public Health Guidance for Emergency Action Planning for Retail Food Establishments  Food establishments must follow MA DPH procedures and the direction of their local board of health, which may be more stringent than the DPH guide.
    Boil Order - See pg. 19 of the DPH guide for procedures to follow during a Boil Order.
    Do Not Drink - See pg. 15 of the DPH guide for procedures to follow during a water interruption incident.
    Centers for Disease Control and Prevention (CDC) - Renal Dialysis Units During a Boil Water Advisory
    US Centers for Disease Control and Prevention Information on E.coli
    Cryptosporidium - EPA Guidance for People with Severely Weakened Immune Systems  

Corrective Actions

In your notice, describe corrective actions you are taking. Listed below are some steps commonly taken by water systems with bacteriological situations. Use one or more of the following actions, if appropriate, or develop your own:

  • We are chlorinating and flushing the water system.
  • We are investigating the source of contamination.
  • We are disinfecting and inspecting the storage tank.
  • We are providing an alternate drinking water source.
  • We are implementing a mandatory water ban to restrict water use during the emergency. We are increasing sampling for coliform bacteria.
  • We are repairing the wellhead seal.
  • The well and/or distribution system has been disinfected.
  • We have increased disinfection levels.
  • We are providing emergency disinfection.


All public notices must meet certain formatting standards. These requirements help prevent the notice from being "buried" in a newspaper and help ensure that consumers can easily read and understand the notice. Notices must:

  • Be displayed in a conspicuous way (where printed or posted);
  • Not contain overly technical language or very small print (notice should be the size of a news article or advertisement, legal size publications are not allowed);
  • Not be formatted in a way that defeats the purpose of the notice; and
  • Not contain language which nullifies the purpose of the notice.

Multilingual Notices

If a large proportion of the population you serve does not speak English, you must provide information in the appropriate language(s) regarding the importance of the notice, or a telephone number or address where consumers may contact the system to obtain a translated copy of the notice.

You may wish to provide notices in multiple languages if non-English-speaking populations are in your service area, whether or not they constitute a large proportion of your service population. Although you are not required to provide full translations of notices, this is strongly recommended for Tier 1 notices and for other violations that pose a serious health risk.

Translations for Public Notification (in 28 languages with do not drink graphics - Washington State Department of Health)

EPA Public Notification Handbook 

Preparing Your Massachusetts Drinking Water Consumer Confidence Report see pages 12 and 13 for language translation requirements per City/Town


For violations and situations requiring Tier 1 notification, you must use one or more of the following methods to distribute notices in a form and manner reasonably calculated to reach all persons served (310 CMR 22.16(2)(c)):

  • Hand or direct delivery
  • Radio and/or television
  • Posting in conspicuous locations
  • Any other delivery method approved by MassDEP

In addition to one (or more) of the above methods, large community systems must publish the Tier 1 public notice within the local newspaper as a one-day advertisement (not legal size), no later than 14 days after the violation, unless otherwise directed by MassDEP. A newspaper article published during the event may serve to satisfy this requirement. A copy must be submitted to MassDEP no later than the time published.

You may need to use additional methods (e.g., newspaper, delivery of multiple copies to hospitals, clinics, or apartment buildings, door hangers, emergency signage, reverse 911, email, internet websites); since notice must be provided in a manner reasonably calculated to reach all persons served.

It is recommended that you notify health professionals in the area of the violation. People may call their doctors with questions about how the violation may affect their health, and the doctors should have the information they need to respond appropriately. In addition, health professionals, including dentists, use tap water during their procedures and need to know of contamination so they can use bottled water.

MassDEP may allow limited distribution only if the violation is in a portion of the distribution that is either physically or hydraulically isolated from other parts of the distribution system.

Problem Corrected Notice

It is a good idea to issue a "problem corrected notice" when the violation is resolved and update website information, as applicable.

Flush All Taps when the Boil Water Order is Lifted

When flushing it is important to carefully follow the instructions provided. Flushing your household and building water lines including: interior and exterior faucets, showers, water/ice dispensers, water treatment units, etc. Water heaters may need to be disinfected and flushed to remove any contaminated water. Some types of water treatment devices may need to be disinfected or replaced before being used. Check with the manufacturer for details. See more information about flushing after a boil water notice on the instructions for post boil-water orders section of the consumer information on boil orders page.


Within 10 days from the time you issue the notice, send a copy of each type of notice and a certification that you have met all the public notice requirements to your regional MassDEP office and local board of health (310 CMR 22.15(3)(b)). You must send certifications for both initial and any repeat notices. When you certify, you are also stating that you will meet future requirements for notifying new billing units and new customers of the violation or situation.

Other Requirements and Technical Assistance

Emergency Response Report

Within 30 days of a Tier 1 emergency, complete and submit an Emergency Response Report (ER Report - Form 1) to MassDEP in accordance with 310 CMR 22.15(9)(c), unless otherwise determined by MassDEP.

The Emergency Response Report shall include the following information at a minimum: detailed timeline of the incident and response; evaluation of the incident; recommendations for improvements to emergency response planning, training, and communication; recommendations for improvements to water system operations, staffing, and budget; timeline for making all recommended changes; and an updated emergency response plan except for those items that are security sensitive.

Emergency Report (Form 1) PDF version  or Emergency Report (Form  1) doc version

Emergency Response Report Guidance 

GWR Response

The GWR requires ground water systems at risk of microbial contamination to take corrective action to protect consumers from harmful bacteria and viruses. Notifying the public of potential risks is a key element of this risk-targeted approach. Procedures for notifying the public differ depending on whether a system is a community or a non-community water system (NCWS).


Community water systems must include information about total coliform MCL violations, fecal indicator detections (E.coli or enterococci), TT violations, and monitoring violations in their annual Consumer Confidence Report (CCR), including:

Total Coliform Rule (regulated contaminant table):

  • The total number of E.coli positive samples - (in the distribution system)
  • The highest monthly number (or percentage) of positive samples (in the distribution system)

Ground Water Rule (regulated contaminant table):

  • The total number and dates of positive samples (in the source water) - E.coli and/or enterococci

Technical Assistance

The EPA/ASDWA Public Notification Handbook provides additional aids to help water systems develop notices for violations and situations. An electronic copy of the Public Notification Handbook and Public Notification Handbook for Transient Non-Community Water Systems is available at EPA's website. Please note that the EPA/ASDWA Handbook templates are non-state-specific, so Massachusetts water suppliers are required to use the MassDEP version of the templates for compliance purposes.


MassDEP Public Notification Forms and Templates are designed to help operators create public notices for a variety of violations. However, it is important to note that the templates included here are not inclusive and may not be appropriate for all violations and situations. Depending on the severity of your violation or situation, it may be necessary to modify the instructions you give to consumers or to change the timing of the notice. In some cases, MassDEP may provide additional instructions and custom public notice to fit the situation. 

The Public Notification Templates are appropriate for hand delivery or a newspaper notice. Notices may need to be modified for radio or TV distribution. If you modify the notice, you must still include all required elements and leave the health effects language in italics unchanged. This language is mandatory (310 CMR 22.16(5)(d)). If you post or hand-deliver, print your notice on letterhead, if available.

Do Not Drink Notice

In cases where it is not practical for consumers to boil water, such as users of a non-community system, it may be necessary to modify the instructions you give to consumers, such as a "Do Not Drink" notice and direct consumers to use an alternative source of potable water.

Additional Resources for