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.
Beginning April 1, 2016, all public water systems were required to be in compliance with the RTCR.
Following are guidance documents, forms, and links to resources intended to help Maine public water systems understand and comply with the requirements of the RTCR.
Quick Reference Guides
The Quick Reference Guides below provide an overview of the RTCR.
- For seasonal public water systems (only open a portion of the year):
- All other public water systems:
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 must be completed — with certification submitted to the Drinking Water Program — before a PWS opens and begins operating for the season.
For example, if a seasonal public water system opens on May 1, start-up procedures must be completed and the certification form provided to the DWP before May 1 of that year.
Approved Start-up Procedures:
- Seasonal Public Water Systems Using Groundwater (PDF)
- Seasonal Public Water Systems Using Surface Water (PDF)
Sampling Site Plans
The RTCR requires that total coliform samples be collected by public water systems at sites that are representative of water quality throughout the distribution. Sampling locations must correspond with those identified in a written sampling site plan that is 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.
- DWP Policy and Procedure on Creation, Review and Approval of Sampling Site Plans (PDF)
- Sample Site Plan Templates: PDF; or Microsoft Word (DOCX)
For public water systems serving a population of 1,000 or fewer: Public Water System 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.
Sampling Site Plan Approval Checklists:
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.
Determining Source Protection Status Under the Revised Total Coliform Rule (PDF): This 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 of this website.
Public water systems that have multiple positive total coliform bacteria sample results are required to conduct a 'Level Assessment', an in-depth assessment of their water system to identify problems and determine appropriate corrective actions. There are two levels of assessment — Level 1 and Level 2 — based on the severity or frequency of the problem. For more information on level assessments and corrective actions, visit the RTCR Assessments and Corrective Actions page of this website.
- EPA Quick Reference Guide to RTCR (EPA) (PDF)
- A Small Systems Guide to the Total Coliform Rule (Community Water Systems) (EPA) (PDF)
- EPA's Total Coliform Rule: A Handbook for Small Noncommunity Water Systems serving less than 3,300 persons (EPA) (PDF)
- Sampling Information
- Seasonal Water Systems
- Technical Assistance
- Source Water Protection