Division of Environmental and Community Health

Maine Center for Disease Control & Prevention

A Division of the Maine Department of Health and Human Services

DHHSMeCDCEnvironmental and Community HealthDrinking WaterRevised Total Coliform Rule (RTCR)

Revised Total Coliform Rule (RTCR)

On February 13, 2013, the Environmental Protection Agency (EPA) made revisions to the 1989 Total Coliform Rule in an effort to provide greater public health protection. The revisions, based on recommendations from a federal advisory committee, are known as the Revised Total Coliform Rule or RTCR.

The RTCR establishes a maximum contaminant level (MCL) for E. Coli and uses E. Coli and total coliforms to initiate a "find and fix" approach to address fecal contamination that could enter into the distribution system.  It requires public water systems to perform assessments to identify sanitary defects and subsequently take action to correction them.

All public water systems must comply with the requirements of the RTCR beginning April 1, 2016.

The guidance documents, forms, and links to resources on this page are provided to help Maine public water systems understand, prepare for, and comply with the requirements of the RTCR.

Quick Reference Guides

The Quick Reference Guides below provide an overview of the changes that will result from the RTCR.

Startup Procedures (seasonal water systems only)

Under the RTCR, seasonal water systems must conduct a state approved startup procedure at the beginning of each operating period, before serving water to the public. Seasonal water systems must also certify that they have completed the state-approved startup procedure. The startup procedure with certification must be completed and sent in before you open and begin operating your public water system for the season.

For example, if your seasonal public water system opens on May 1, 2016, you will need to complete the startup procedure and send in the certification form before May 1, 2016.

Sampling Site Plans

The RTCR requires that total coliform samples be collected by public water systems at sites which are representative of water quality throughout the distribution and according to a written sampling site plan subject to State review and approval. Sample site plan requirements under the RTCR include, but are not limited to: establishing sample site locations for routine total coliform samples, repeat total coliform samples, raw water samples, and follow-up total coliform samples. Sample site plans must also identify when samples will be taken during the compliance period.

For public water systems serving a population of 1,000 or fewer: DWP Field Inspectors will review and work with public water systems to create or modify sample site plans that meet the guidelines set forth in the RTCR during routine sanitary surveys or on-site visits after April 1, 2016.

For public water systems serving a population greater than 1,000: Systems must submit a revised sample site plan that meets the sample site plan guidelines set forth in the RTCR to DWP by December 31, 2015 for approval.

Protected Source

Determining whether a public water system has a “protected source” is important under the Revised Total Coliform Rule, as it can impact whether some water systems are eligible for reduced monitoring of Total Coliform bacteria. Similarly, for water systems that have a default monitoring frequency of quarterly for Total Coliform but have been increased to monthly due to a compliance trigger, source protection status is important for determining eligibility to return to a quarterly monitoring frequency.

The Determining Source Protection Status Under the Revised Total Coliform Rule guidance document outlines the criteria for determining the source protections status of a water system under the RTCR. For additional resources on source protection, visit the DWP Source Water Protection page.


The RTCR brings a change in the response to total coliform positive sample results. Water systems that have multiple, positive total coliform bacteria sample results will be required to conduct an assessment of their water system to find any problems and take corrective action. There are two levels of assessments (Level 1 and Level 2) based on the severity or frequency of the problem. For more information on assessments and corrective actions, visit the RTCR Assessments and Corrective Actions page.

Additional Resources