New Mexico
Environment Department

Contact Information:
(505) 827-2855 MAIN // 1-800-219-6157 (toll free)
Environmental Emergencies:
505-827-9329 (24 hrs)

Drinking Water Bureau

Revised Total Coliform Rule (RTCR)

The RTCR is a major revision to the original Total Coliform Rule (TCR).  The RTCR went into effect on April 1, 2016. To read the full text of the RTCR, click here.

Additional information is available on the Association of State Drinking Water Administrators (ASDWA) website, including slides and recorded webinars conducted by the US EPA on the RTCR.  Click here to access that training material.

General Overview

Monitoring Schedule

Public water systems will no longer be allowed to be on a reduced monitoring schedule for Coliform and E.Coli.  All public water systems at a minimum will be required to monitor on a monthly basis.

Drinking Water Distribution System Sampling Plan (DSSP)

The RTCR will take effect on April 1, 2016.  This rule revises the Total Coliform Rule (TCR) and will require that all public water systems update their previous sampling plans.  The DWB has developed a comprehensive Drinking Water Distribution System Sampling Plan (DSSP) Template and Instructions that explains the sampling plan requirements.

Please review the requirements noted in the DSSP and use the Sampling Plan Template in order to develop your water systems’s sampling plan.

Click here to download the DSSP plan, instructions, and template

All public water systems will be required to update and submit their Sampling Plans to DWB no later than April 1, 2016.

Designating Your DSSP RTCR Sample Sites

In order to properly document your water system’s sampling locations, the DWB has developed the RTCR Sample Sites Spreadsheet to assist you with required sampling points.  To request an excel version of the spreadsheet send an email to the RTCR Rule Administrator at Please use the following instructions and spreadsheet to properly document your water system’s sampling locations and provide those locations to DWB:

Step 1 Open the spreadsheet

Step 2 Click the “Enable Editing” button at the top of the spreadsheet

Step 3 Click the yellow dropdown box next to “PWS Name” to find and pick your water system

Step 4 Cell A6 will provide the number of Routine sample sites that you are required to identify in your updated RTCR Sampling Plan

Step 5 Fill in each of the required Routine Sampling Locations in Column C.  Locations must be designated with either a physical address or physical sampling location description

Step 6 Fill in each of the required Repeat Sampling Locations in Column E.  Repeat Sampling Locations must be located within 5 connections upstream and downstream of the address that you listed in Column C and must also be designated with either a physical address or  physical sampling location description

Step 7 Include the Routine and Repeat sampling locations that you identified in this spreadsheet in your revised Distribution System Sampling Plan (DSSP)

Step 8 Save the spreadsheet to your computer

Step 9 Email the filled out Excel spreadsheet and DSSP back to DWB at the following email address:

Guidance Documents

To better assist public water systems with the transition to RTCR, the DWB has developed several Guidance Documents for public water systems.

Seasonal Public Water Systems

Seasonal Public Water Systems will be required to conduct start-up procedures prior to opening for their season.

A Seasonal Public Water System is a non-community water system that is not operated as a public water system (PWS) on a year-round basis and starts-up and shuts-down at the beginning and end of each operating season.  Examples include: campgrounds, fairgrounds, seasonal food service facilities, and ski areas open during part of the year.

Beginning on April 1, 2016, owners/operators of Seasonal Public Water Systems must perform a Seasonal Start-Up Procedure to be in compliance with the Federal Safe Drinking Water Act. The procedure includes flushing, disinfection, and sampling their system prior to opening.

Please use this Seasonal Guidance document to assist you through the requirements of seasonal start-up procedures.

This Seasonal Start-up Procedure Checklist and associated documentation is required to be submitted to NMED DWB at least 10 days prior to your planned opening date.

Large Water System Guidance

Please use this guidance to help you with the key RTCR changes for public water systems with a population of greater than 33,000.

Small Water System Guidance

Please use this guidance to help you with the key RTCR changes for public water systems with a population of less than 1,000.

Repeat Sampling

If your water system has a total Coliform Positive (TC+) or E.Coli positive (EC+) monthly routine sample, you are required to collect repeat samples.  This guidance will assist you with the repeat monitoring requirements.

Additional Required Sampling for Ground Water Systems

In addition to the repeat samples that are required by the RTCR, the Ground Water Rule requires that all ground water systems collect triggered source samples from each ground water source that was in use at the time the total coliform-positive sample was collected.

Additionally, Consecutive Systems that receive water from a system that uses ground water, must notify its wholesale system(s) within 24 hours of being notified of the positive sample.  A wholesale system that receives notice from a consecutive system of a positive total coliform result under routine monitoring of the RTCR must collect a triggered source water sample from its ground water source(s) and analyze the source water sample(s) for a fecal indicator (E. Coli.) within 24 of being notified by the consecutive system.

Ground Water systems that have applied to NMED DWB, approved for and are providing at least 4-log treatment of viruses, may be exempt from triggered source monitoring requirements.

Triggered Source Monitoring Fact Sheet

Triggered Assessments

When sampling results show that your public water system may be vulnerable to  contamination, the public water system must perform an assessment (Level 1 or Level 2) and FIND AND FIX ANY “SANITARY DEFECTS.”  This guidance will assist you with the requirements of triggered assessments.

Level 1 Assessments may only be conducted by SWA, WS3, or WS4 certified operators or any Level of operator that attends an NMED-approved 8 Hour RTCR Training Session.

Level 2 Assessments may only be conducted by a WS3 or WS4 certified operator or any Level of operator that attends an NMED-approved Hour RTCR Training Session.

RTCR Training

DWB has been offering RTCR trainings throughout the State.  These trainings are designed to provide system representatives with a comprehensive understanding of the RTCR requirements, how they differ from the TCR, and to provide the training needed for operators to become approved to conduct Level 1 or Level 2 assessments.  Please go to the DWB Training Page to check the schedule for upcoming classes.


You can contact your assigned Compliance Officer or the Technical Services Program Manager if you have questions. Please go to the DWB Contact Us page to find the name and contact information of your assigned Compliance Officer.