An official website of the United States government.

This is not the current EPA website. To navigate to the current EPA website, please go to www.epa.gov. This website is historical material reflecting the EPA website as it existed on January 19, 2021. This website is no longer updated and links to external websites and some internal pages may not work. More information »

Drinking Water Requirements for States and Public Water Systems

Long Term 2 Enhanced Surface Water Treatment Rule Documents

On this page:

Overview

The Long Term 2 Enhanced Surface Water Treatment Rule addresses the health effects associated with Cryptosporidium in surface water used as a drinking water supply. These guidance documents provide information on the source water sampling monitoring requirements for Cryptosporidium and the treatment requirements for vulnerable surface water supplies based on sampling.

Fact Sheets for LT2 Rule

Top of Page

Source Water Monitoring Guidance for Public Water Systems
Description: This guidance provides a review of source water monitoring provisions. Surface water systems are required to conduct source water monitoring for Cryptosporidium, E. coli, and turbidity. This manual provides direction to the systems on how, where and when to monitor and how to report the data. It summarizes how the data can be evaluated and used to determine risk bin classification.

Target Audience: Surface water systems, laboratories, states, tribes, other primacy agencies

Top of Page

Microbial Laboratory Guidance
Description: The Microbial Laboratory Guidance manual provides information regarding analytical methods required for analysis of Cryptosporidium and E. coli samples under the LT2 rule.
Target Audience: Analytical laboratories performing LT2 Cryptosporidium and E. coli analyses

Top of Page

Complying with the Long Term 2 Enhanced Surface Water Treatment Rule: Small Entity Compliance Guide (Revised April 2009)
Description: This guide contains a general introduction and background for the LT2 rule. It describes the specific requirements of the LT2 rule and provides information on how to comply with those requirements.
Target Audience: Small surface water systems.

Top of Page

Long Term 2 Enhanced Surface Water Treatment Rule: Toolbox Guidance Manual
Description: Surface water systems required to provide treatment under the LT2 rule can select from numerous “microbial toolbox” treatment options to meet treatment requirements. This manual provides general information on the LT2 regulation and treatment requirements.

Target Audience: Surface water systems required to install treatment under the LT2 rule.

Top of Page

Ultraviolet Disinfection Guidance Manual Final
Description: Surface water systems required to provide treatment under the LT2 rule can utilize ultraviolet disinfection as one of the “microbial toolbox” treatment options. This manual provides background information and guidance on UV light, microbial response to UV light, and UV reactors.
Target Audience: Surface water systems required to install treatment under the LT2 rule

Top of Page

Membrane Filtration Guidance Manual
Description: Surface water systems required to provide treatment under the LT2 rule can utilize membrane filtration as one of the “microbial toolbox” treatment options. This manual is designed to provide surface water systems with an overview of membrane filtration. It details requirements for membrane filtration under the LT2 rule; membrane filtration system design and operation; membrane filtration testing requirements; and startup and implementation considerations.
Target Audience: Surface water systems required to install treatment under the LT2 rule.

Top of Page

Simultaneous Compliance Guidance Manual for Stage 2 Rules
EPA 815-R-07-017, May 2007
Description: This manual discusses the issues that systems will face as they evaluate and implement changes necessary to comply with the Stage 2 DBPR and the LT2ESWTR. Systems are still required to comply with earlier rules such as the Total Coliform Rule and Lead and Copper Rule. This guidance manual to will systems to evaluate different compliance strategies and technologies.
Target audience: Public water systems making treatment and operational changes to comply, states.

Top of Page

Low-pressure Membrane Filtration for Pathogen Removal: Application, Implementation, and Regulatory Issues
Description: This report summarizes the state of membrane filtration in 2000 as applied for pathogen removal. The results of the study summarized in this report were used to support the development of the regulatory framework and guidance for membrane filtration under the LT2 rule.
Target audience: Public water systems and states.

Top of Page

LT2: Cryptosporidium & E. coli Sample Collection Recommendations Pocket Guide
The following links contain a 'Pocket Reference' version of the Cryptosporidium & E. coli sample collection module. Select the first link to view a printable version of the pocket guide for use with 8.5" x 11" paper. Select the second link for a viewable version of the water-resistant pocket guide (can be scaled up to print on any size paper). Copies of the water-resistant color pocket guide can be ordered by using its document number [817-K-06-002] and contacting the National Service Center for Environmental Publications at 1-800-490-9198.


For more information, please see the Surface Water Treatment Rules page.

Top of Page