Stage 2 Disinfection By-Products Rule

Disinfection By-Products (DBPs) form when disinfectants, such as chlorine, are added to drinking water and react with naturally occurring organic matter. These by-products can have adverse health effects, including cancer. DBPs in drinking water are regulated by the Stage 2 Disinfection By-Product Rule, which applies to all community water systems and non-transient non-community water systems by limiting the exposure to DBPs, specifically Total Trihalomethanes (TTHM) and Total Haloacetic Acids (HAA5). Other drinking water contaminants monitored through the Stage 2 Rule include chlorite, bromate, chlorine/chloramines, and chlorine dioxide disinfectants.

Helpful Documents

  1. Chlorine Dioxide and Chlorite Log (XLS)
  2. Chlorine Dioxide and Chlorite Log Form (PDF)
  3. Daily Chlorine Residual Log Form (DOC)
  4. HAA and TTHM Sample Collection Instructions (PDF)
  5. How to Determine Compliance with TTHM and HAA5 MCLs (PDF)
  6. Manual Quarterly Bromate Report (PDF)
  7. MRDL Log Form (PDF)
  8. MRDL Log Form Excel Format (XLS)
  9. Stage 2 Compliance Report Template Form (XLS)
  10. Stage 2 Monitoring Plan Form (DOC)
  11. TOC Monitoring Report Form (XLS)
  12. TOC Removal Compliance Calculation (XLS)
  13. TOC Sample Collection Instructions (PDF)