1. Overview of Distribution System Optimization (DSO) Training Presentation 1 DSO Training April 2015

2. Regions covered by TA’s

3. OEL Form

4. Water Treatment & Distribution Optimization Overview  History  Challenges  Approach

5. Optimization is About Public Health Protection  Initial focus of optimization was prevention of waterborne disease outbreaks related to microbial contaminants.  Giardia and Cryptosporidium routinely detected in water supplies and confirmed source of outbreaks.  Meeting existing compliance levels was not always effective for preventing outbreaks.

6. Multiple Barrier Concept in Water Treatment  Optimization requires treatment beyond regulatory levels.  Focus on multiple-barrier strategy to enhance water system performance.  Particle removal (i.e., turbidity): Coagulation/flocculation + sedimentation + filtration  Disinfection Sedimentation Barrier Filtration Barrier Disinfection Barrier Variable Quality Source Water Turbidity Goal Disinfection Goal Coagulant Addition Disinfectant Addition Coagulation Flocculation Barrier Disinfection Goal High Quality Finished Water

7. Optimization Beyond Turbidity Focused on DBP Control  Stage 1 D/DBP Rule:  Limits based on system-wide running annual average.  Stage 2 D/DBP Rule (current):  Limits based on running annual average at specific sample sites.  New challenge to achieve microbial optimization goals while minimizing DBP formation.

8.  EKY DS DBP PBT  First DS DBP Series in KY (Pilot)  June 2013-October 2014  6 Systems Complete Campton Water System Campton Water System Hazard Water Department Hazard Water Department Knott County Water & Sewer District Knott County Water & Sewer District Manchester Water Works Manchester Water Works Martin County Water District No.1 Martin County Water District No.1 Mountain Water District No.1—Marrowbone Mountain Water District No.1—Marrowbone DS DBP PBT

9.  EKY DS DBP PBT (cont.)  6 Sessions Performance Goals & Monitoring Performance Goals & Monitoring Identifying Critical Sites Identifying Critical Sites Impacts of Storage Tanks on Water Quality Impacts of Storage Tanks on Water Quality Water Storage Tanks—Assessments & Special Studies Water Storage Tanks—Assessments & Special Studies Flushing & Control Strategies Flushing & Control Strategies Project Wrap-Up & Ongoing Optimization Activities Project Wrap-Up & Ongoing Optimization Activities

10. DS DBP PBT  EKY DS DBP PBT (cont.)  Outcome Goals have been established Goals have been established Operators know their systems better Operators know their systems better Critical monitoring locations increase system monitoring Critical monitoring locations increase system monitoring Decrease in water age Decrease in water age Flushing Flushing Tank operational changes Tank operational changes These 6 systems have a plan going forward These 6 systems have a plan going forward In conclusion…improvements in these distribution systems have decreased water age and as a result have improved water quality! In conclusion…improvements in these distribution systems have decreased water age and as a result have improved water quality!

11. Next Step – DSO With Multiple Utilities using a 1-Day Training Approach  Performance based training (PBT) is an effective approach for transferring priority setting and problem solving skills to a limited group of water systems (4 to 8 systems ideal).  This training intends to teach PBT concepts to more water systems using a modified approach:  DSO concepts will be introduced to a larger group of water systems as a 1-day training module.

12. Overcoming Challenges to Water Optimization Changing Attitudes and Perceptions

13. Defining A Water Professional  Who is responsible for water quality (in the plant?; in the distribution system?)  What are the characteristics and attributes of these individuals

14. Summary  Distribution system optimization is a new field of learning for everyone.  Initial efforts focused on working with one utility at a time.  Performance Based Training is a proven approach for applying optimization principles to a group of water utilities.  A distribution system optimization 1-day training approach is being piloted to reach more water systems.

15. Why Optimize in the Distribution System? Motivation for Optimization and Performance Goals Presentation #1B DSO Training April 2015

16. Overview  Motivation for distribution system optimization  Optimization focus on water quality  Distribution system optimization goals

17. WHY? The Motivation

18. Why Optimize the Distribution System?  Public health protection:  On average, from 1971 to 2002, a distribution-related outbreak caused 152 illnesses, with the largest causing as many as 5,000 illnesses (Craun et al., 2006).  Public health risks include: Microbial contaminants (e.g., Salmonella, E. coli, Legionella, Naegleria fowleri) Chemical contaminants (e.g., organic, inorganic, disinfection byproducts ~ TTHMs, HAAs)  Secondary benefits:  Proactive approach to meeting compliance.  Fewer complaints, happier customers!

19. Why Optimize in the Distribution System? Alamosa, Colorado Case Study  System Description  Serves 8,900 plus 1,000 through purchase systems  Ground water with disinfection waiver… but is this really different from a SW system that doesn’t maintain a residual?  Three storage tanks (1 ground level)  50 miles of pipe  In compliance with all regulatory requirements, except arsenic  Total coliform samples were negative prior to the outbreak  Salmonella contamination  Generally spread through human or animal feces ~ rarely through drinking water

20. Suspected Cause of Outbreak Inadequate Physical and Disinfection Barriers  Physical contamination of Weber Reservoir (ground storage tank): o Cracks and holes could allow small animal or water (snow melt?) to contaminate the tank o Evidence of wildlife near (but not inside) the tank o Tanks supplied majority (~75%) of the system o Salmonella contamination was found throughout the system  No disinfection barrier in the system!

21. Impacts of the Outbreak were Devastating!  Public Health:  442 illness reported (as many as 1,300 sick?); 20 hospitalized, 1 death  Community:  All schools closed and most child care facilities  Several restaurants closed  Public Relations “challenge” for water system ~ 3 weeks without safe water  Costs estimated around $1 Million to City, County and State

22. Key Lessons Learned from Alamosa  Doesn’t take much to impact an entire system (suspect just 1 bird…)  Routine coliform monitoring did not indicate a problem o Consistent with other waterborne disease outbreaks (Gideon, MO and Cabool MO)  A significant team (from all over Colorado) was needed to provide an alternate water supply, collect and measure WQ samples, make repairs, clean tanks, disinfect and flush the system, and notify citizens  The citizens and businesses were without safe drinking water for nearly three weeks

23. HOW? Protecting Water Quality and Public Health through Optimization

24. Distribution System: The Last Barrier(s) to Public Health Protection  Protecting the physical barrier/ infrastructure from contamination (e.g., maintaining pressure, preventing backflow, protecting storage tanks, etc.)  Providing a disinfection barrier against contamination and water quality deterioration

25. The Disinfection Barrier: What Research Says…  Importance of providing a disinfectant residual barrier: o Studies indicate that a free chlorine residual of 0.2 to 0.5 mg/L is needed to provide adequate protection against microbial contamination (Baribeau, 2005). o Systems that maintained free chlorine residual of greater than 0.20 mg/L had at least 50% lower rate of coliform occurrence (LeChevallier, 1996).  Importance of routinely monitoring disinfectant residual: o Free chlorine residual is an excellent indicator of microbial contamination in the distribution system (Helbling and VanBriesen, 2008). In other words… chlorine residual verifies that the physical (and disinfection) barriers are in place.

26. The Disinfection Barrier: What We’ve Learned…  Area Wide Optimization Program (AWOP) distribution system work indicates: o Water systems aren’t monitoring throughout their systems o At critical sites, free chlorine residual is not maintained ≥ 0.2 mg/L.

27. The Flip Side: Disinfection Byproduct (DBP) Formation  DBPs are formed when chlorine (or other disinfectant) reacts with organics (total organic carbon) in the water  Formation is impacted by:  Reactions within the bulk water (due to increased chlorine, temperature, organics, etc.)  Reactions within the distribution system infrastructure (e.g., biofilm, etc.)  Water age (time)  Organic Matter (TOC) Chlorine DBPs (TTHM & HAA5, others)

28. Risks Must be Balanced Increase Chlorine = Increase DBPs Decrease Chlorine = Increase Microbial Risk Bladder Cancer ReproductiveDisorder Diarrhea Kidney Failure Hemolytic Uremic Syndrome Vomiting

29. Optimized Performance Starts by Setting Water Quality Goals

30. Disinfection Performance Goal Disinfection Goal: Maintain ≥ 0.20 mg/L free chlorine At all monitoring sites in the distribution system, at all times.  Regulatory Requirement is 0.20 mg/L free chlorine

31. DBP Performance Goals: Individual Site LRAA Goals  LRAA = locational running annual average.  Applies to the most recent four quarters of data (LRAA).  Requires a minimum of four quarters of DBP data at each sample site assessed.  Stage 2 D/DBP Rule MCL is 80 ppb for TTHM and 60 ppb for HAA5 Individual Site LRAA Goal: TTHM LRAA ≤ 70 ppb HAA5 LRAA ≤ 50 ppb At all sample sites in the distribution system

32. Plant Effluent Individual Site LRAA goal must be met at all sample locations in the system. TTHM Results (this site): Q2 05: 45 ppb Q3 05: 56 ppb Q4 05: 79 ppb Q1 06: 60 ppb Meets performance goal (TTHM LRAA ≤ 70 ppb) LRAA = 60 ppb

33. DBP Performance Goals: Long Term System Goals  Calculated by averaging past 8 quarterly LRAA values (highest LRAA each quarter used in calculation).  Requires 11 quarters of data for a site to be assessed.  Justification: provides safety factor for meeting Stage 2 regulations. Long-Term System Goal: Average of Max TTHM LRAA values ≤ 60 ppb Average of Max HAA5 LRAA values ≤ 40 ppb Applied throughout the system

34. Conclusions  The Alamosa outbreak and other recent water quality crises provided some valuable lessons on why optimization is important.  This training will focus on maintaining the distribution system barrier:  Monitoring and maintaining the disinfection barrier.  Monitoring DBPs (at compliance locations) to balance microbial and DBP risks.

35. References Baribeau, H., Gagnon, G., Hofman, R., and Warn, E. (2005). Impact of Distribution System Water Quality on Disinfection Efficacy. AWWA Research Foundation, Denver, CO. Centers for Disease Control and Prevention. (1991-2006). Surveillance for Waterborne Disease and Outbreaks Associated with Drinking Water and Water not Intended for Drinking. Morbidity and Mortality Weekly Report. Reports dated 1991-2006. From http://www.cdc.gov/mmWR. http://www.cdc.gov/mmWR Craun, M., Craun, G., Calderon, R., and Beach, M. (2006). Waterborne Disease Outbreaks in the United States. Journal of Water and Health, 04.Suppl 2, 2006. Retrieved August 14, 2009 from http://www.epa.gov/nheerl/articles/2006/waterborne_disease/waterborne_outbreaks.pdf. http://www.epa.gov/nheerl/articles/2006/waterborne_disease/waterborne_outbreaks.pdf Craun, G. and Calderon, R. Waterborne disease outbreaks Caused by Distribution System Deficiencies. Journal AWWA, September 2001. U.S. EPA. 2007. Estimating the Burden of Disease Associated with Outbreaks Reported to the U.S. Waterborne Disease Outbreak Surveillance System: Identifying Limitations and Improvements. U.S. Environmental Protection Agency, National Center for Environmental Assessment, Cincinnati, OH. EPA/600/R-06/069. Falco, R. and Williams, S. (November 2009) Waterborne Salmonella Outbreak in Alamosa, Colorado March and April 2008: Outbreak Identification, Response, and Investigation. From http://www.cdphe.state.co.us/wq/drinkingwater/pdf/AlamosaInvestRpt.pdf.http://www.cdphe.state.co.us/wq/drinkingwater/pdf/AlamosaInvestRpt.pdf Helbling, D.E. and J.M VanBriesen, Continuous monitoring of residual chlorine concentrations in response to controlled microbial intrusions in a laboratory-scale distribution system. Water Research,42(2008) 3162-3172. LeChevallier, M.W., Welch, N.J, and D.B. Smith, Full-Scale Studies of Factors Related to Coliform Regrowth in Drinking Water, Applied and Environmental Microbiology, p. 2201-2211, July 1996. National Research Council. (2006) Drinking Water Distribution Systems Assessing and Reducing Risks. Washington, DC: National Academies Press. City of Alamosa 2008 financial report. http://www.about-salmonella.com/salmonella_outbreaks/view/alamosa-colorado-municipal-water-system-salmonella-outbreak/). Pueblo Chieftain article from May 2, 2008 “Cost figures for salmonella outbreak trickle in.”