Long Term 1 Enhanced Surface Water Treatment Rule

EPA finalized the Long Term 1 Enhanced Surface Water Treatment Rule (LT1ESWTR) on January 14th, 2002. The purposes of the LT1ESWTR are to improve control of microbial pathogens, specifically the protozoan Cryptosporidium, in drinking water, and address risk trade-offs with disinfection byproducts.

The rule will require certain public water systems to meet strengthened filtration requirements. It will also require systems to calculate levels of microbial inactivation to ensure that microbial protection is not jeopardized if systems make changes to comply with requirements of the Stage 1 Disinfectants and Disinfection Byproducts Rule (Stage 1-DBPR). This rule, which addresses subpart H systems serving fewer than 10,000 persons, builds upon the framework established for larger systems in the Interim Enhanced Surface Water Treatment Rule (IESWTR).

Final Rule

• Final Long Term 1 Enhanced Surface Water Treatment Rule (67 FR 1812, January 14, 2002) (Read Online)
• Fact Sheets
  • Final Long Term 1 Enhanced Surface Water Treatment Rule (EPA 815-F-02-001, January 2002)

Guidance Documents (ALL ABOUT PDF FILES)

• Long Term 1 Enhanced Surface Water Treatment Rule (LT1ESWTR) Implementation Guidance (EPA 816-R-04-008, August, 2004)
  • Implementation Guidance Document (544 K PDF FILE, 162 pgs)
  • Appendices ( 4.5 M PDF FILE, 210 pgs)
• Long Term 1 Enhanced Surface Water Treatment Rule (LT1ESWTR) Implementation Turbidity Provisions - Technical Guidance Manual (EPA 816-R-04-007, August, 2004) (6.1 M PDF FILE, 254 pgs)
• Long Term 1 Enhanced Surface Water Treatment Rule: A Quick Reference Guide (EPA 816-F-02-001) (298 K PDF FILE 2 pgs)
• Long Term 1 Enhanced Surface Water Treatment Rule (LT1ESWTR) Disinfection Profiling and Benchmarking Technical Guidance Manual (EPA 816-R-03-004, May 2003) (4 M PDF FILE, 210 pgs)
• Disinfection Profile Spreadsheet, April 25, 2006
• Long Form (Microsoft Excel File 2.6 M)
• Short Form (Microsoft Excel File 1.2M)
• Web-based Version - LT1 eProfiler

Related Links

• Alternative Disinfectants and Oxidants Guidance Manual (EPA 815-R-99-014, April 1999)
• M/DBP Simultaneous Compliance Manual (EPA-815-R-99-015, August 1999)
• Guidance Manual for Conducting Sanitary Surveys of Public Water Systems; Surface Water and Ground Water Under the Direct Influence (GWUDI) (EPA 815-R-99-016, April 1999)
• Uncovered Finished Water Reservoirs Guidance Manual (EPA 815-R-99-011, April 1999)
• Optimizing Water Treatment Plant Performance Using the Composite Correction Program (EPA 625-6-9-027, August 1998)
  The following handbook provides detailed information on Comprehensive Performance Evaluations (CPEs):
  • Table of Contents (154 K PDF FILE, 12 pgs) (ALL ABOUT PDF FILES)
  • Chapters 1 through 8 (926 K PDF FILE, 115 pgs) (ALL ABOUT PDF FILES)
  • Appendices A through N (1.2 M PDF FILE, 132 pgs) (ALL ABOUT PDF FILES)

Additional guidance materials for the Long Term 1 Enhanced Surface Water Treatment Rule are currently under development. Please check back for updates to the site.

Training

• Drinking Water Academy's Surface Water Treatment Rules Training Materials

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