Recent Findings on Developing Public Health Guidance for Decentralized Non-Potable Water Systems

Transcription

1 Recent Findings on Developing Public Health Guidance for Decentralized Non-Potable Water Systems April 13, 2017 WateReuse Webcast Series 2017 by the WateReuse Association

2 A Few Notes Before We Start Today s webcast will be 90 minutes. There are 1.5 Professional Development Hours (PDHs) available for this webcast. A PDF of today s presentation can be downloaded when you complete the survey at the conclusion of this webcast. If you have questions for the presenters please send a message by typing it into the chat box located on the panel on the left side of your screen. 2

3 Acknowledgments Special thanks to the Water Research Foundation for co-funding this project. Thank you to the Expert Panel, Public Health Coalition, Stakeholder Advisory Committee, and San Francisco Public Utilities Commission (SFPUC) for their contributions to this project. 3

4 Today s Presenters Paula Kehoe Sybil Sharvelle Harold Leverenz San Francisco Public Utilities Commission Colorado State University / One Water Solutions Institute University of California, Davis 4

5 Today s Agenda Intro & Background Research Methods and Findings from the Report Evaluation and Implementation of DNWS Putting Research into Practice the National Blue Ribbon Commission Questions with Audience Risk-Based Framework for the Development of Public Health Guidance for Decentralized Non-Potable Water Systems (WE&RF Project No. SIWM10C15) Available at: 5

6 Why focus on Onsite Non-Potable Water Systems? Communities looking for new ways to develop and manage local water supplies Communities looking to implement One Water Solutions Onsite water systems are already installed in some communities across the U.S.

7 Capturing and Treating Water for Non-Potable Reuse Wastewater from toilets, dishwashers, kitchen sinks, and utility sinks Precipitation collected from roofs and above-grade surfaces Precipitation collected at or below grade Wastewater from clothes washers, bathtubs, showers, and bathroom sinks Nuisance groundwater from dewatering operations

8 Providing Oversight of Onsite Non-potable Water Systems

9 Integrating Decentralized and Centralized Infrastructure

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11 Partnering with 16 Utilities and Public Health Agencies

12 Identifying Common Issues and Research Needs Oversight and management programs are needed on the local level Consistent water quality criteria and monitoring are needed to protect public health

13 Available at:

14 10 Steps for Developing a Local Program

15 Expanding Partnership to Research Risk Based Public Health Guidance

16 Decentralized Non-Potable Water Systems (DNWS) A system in which water from local sources is collected, treated, and used for non-potable applications at the building to district/neighborhood scale generally at a location close to the point of generation.

17 Systems are Happening, But. What are the appropriate water quality standards for DNW Systems? How can ensure safe water is delivered at all times? How can we ensure long term reliability of DNW Systems?

18 Water Quality: Graywater Use to Flush Toilets BOD 5 (mg L -1 ) TSS (mg L -1 ) Turbidity (NTU) Total Coliform (cfu/ 100ml) E. Coli (cfu/ 100ml) Disinfection California mg/l residual chlorine New Mexico Oregon Georgia Texas Massachusetts Wisconsin Colorado mg L -1 residual chlorine mg/l residual chlorine Typical Graywater N/A

19 Roof Runoff: Indoor Use Turbidity (NTU) E. Coli (CFU/100ml) Total Coliforms (CFU/100ml) California 10 < Texas - < 100 < 500 Georgia - < 100 < 500 Graywater Use for Toilet Flushing: Total Coliforms: CFU/100ml E. Coli: CFU/100ml

20 Where we are now with DNWS. State health departments and regulatory agencies need guidance on appropriate water quality standards Current water quality standards are not risk based Everyone has been looking to others for development of standards Guidance on requirements to ensure reliability is needed

21 .. A risk-based approach that is practical for implementation is needed

22 NWRI Panel formed Sybil Sharvelle, Ph.D. Nicholas Ashbolt, Ph.D. Edward Clerico, P.E. Robert Hultquist, P.E. Harold Leverenz, Ph.D. Adam Olivieri, DrPH, P.E.

23 Arizona Department of Environmental Quality Austin Water Utility California State Water Resources Control Board, Division of Drinking Water City of Santa Monica, Office of Sustainability and the Environment Colorado Department of Public Health and Environment County of Los Angeles Public Health Denver Water DC Water District of Columbia Department of Energy and Environment Hawaii State Department of Public Health Los Angeles Department of Water and Power Minnesota Department of Health New York City Department of Environmental Protection Portland Water Bureau Province of Alberta Municipal Affairs, Safety Services San Francisco Department of Public Health San Francisco Public Utilities Commission Santa Monica Public Works Seattle Public Utilities United States Environmental Protection Agency, Office of Research & Development Washington State Department of Health Stakeholder Engagement

24 Purpose of this Framework Provide additional information and guidance to state and local health departments that allows these agencies to consider development of a DNWS program that adequately protects public health Developed to address non-single residence applications (multi-user buildings and district/neighborhood scale) Source waters Blackwater Graywater Domestic wastewater Roof runoff Stormwater Condensate Foundation water Nonpotable end uses Toilet flushing Clothes washing Cooling tower Unrestricted-access municipal irrigation

25 Framework for DNWS (Based on WHO Water Safety Plan)

26 Process for DNWS Design Select appropriate log reduction target (LRT) for end use Select appropriate treatment process train to achieve LRT Professional Engineer approved Management Plan Specify Responsible Management Entity (RME) Level (1-3) Designate RME Roles and Responsibilities Permit Application Report Submission Specifies design, RME, assurance of reliability, commissioning plan, O&M plan, and plan for distribution system management Signed off by Registered Professional Engineer and approved by regulatory agency Construction and Commissioning Field verification when required Submission of Commisioning Report (feild verification results and final monitoring plan) Operational Monitoring Continuous monitoring at high frequency for surrogate water quality and/or operational parameters correlated to LRTs Controls for out of compliance Reporting Violations and incidents Routine reporting via format that is simple to review Approval and enforcement by regulatory agency

27 Risk-Based Management Considerations

28 World Health Organization Approach for Pathogen Reduction Targets 28

29 Log 10 Pathogen Reduction Targets (Table 3-3) Log 10 Reduction Targets for 10-4 (10-2 ) / person y Benchmarks Water Use Scenario Enteric Virus Parasitic Protozoa Enteric Bacteria Domestic Wastewater or Blackwater Unrestricted irrigation 8.0 (6.0) 7.0 (5.0) 6.0 (4.0) Indoor use 8.5 (6.5) 7.0 (5.0) 6.0 (4.0) Graywater Unrestricted irrigation 5.5 (3.5) 4.5 (2.5) 3.5 (1.5) Indoor use 6.0 (4.0) 4.5 (2.5) 3.5 (1.5) Stormwater (10-1 Dilution) Unrestricted irrigation 5.0 (3.0) 4.5 (2.5) 4.0 (2.0) Indoor use 5.5 (3.5) 5.5 (3.5) 5.0 (3.0) Stormwater (10-3 Dilution) Unrestricted irrigation 3.0 (1.0) 2.5 (0.5) 2.0 (0.0) Indoor use 3.5 (1.5) 3.5 (1.5) 3.0 (1.0) Roof Runoff Water Unrestricted irrigation Not applicable No data 3.5 (1.5) Indoor use Not applicable No data 3.5 (1.5)

30 Achieving Pathogen LRTs Example log reduction values (LRVs) for Disinfectants Disinfectant Unit Dose for corresponding LRV 1-log 2-log 3-log 4-log Chlorine (free) mg min/l Chloramine b mg min/l Peracetic acid mg min/l NA NA NA NA Ozone mg min/l UV radiation c mj/cm Advanced oxidation d,e mj/cm Pasteurization (60 C) s

31 Management

32 Monitoring Routine monitoring of indicator organisms does not provide real time information required for operation of DNWS Cost prohibitive A new monitoring approach: Validation testing Start-up and Commissioning Field verification monitoring Performance target confirmation via challenge testing Continuous verification monitoring Ongoing verification of system performance Continuous observations Surrogate parameters correlated with LRTs Controls for out of specification

33 Permitting and Reporting 1. Draft Project Application Report (PAR) submitted, including proposed uses and treatment (if this step is allowed by the jurisdiction s process and it is justified by the project complexity) 2. Final PAR submitted, including plans and specifications, a commissioning plan, and O&M plan 3. Facility Commissioning Report, including results from field verification, and a final monitoring plan, submitted 4. Project permit decision Routine reporting: simple to review Violations and incidents promptly reported

34 Summary Design Select appropriate log reduction target (LRT) for end use Select appropriate treatment process train to achieve LRT Professional Engineer approved Management Plan Specify Responsible Management Entity (RME) Level (1-3) Designate RME Roles and Responsibilities Permit Application Report Submission Specifies design, RME, assurance of reliability, commissioning plan, O&M plan, and plan for distribution system management Signed off by Registered Professional Engineer and approved by regulatory agency Construction and Commissioning Field verification when required Submission of Commisioning Report (feild verification results and final monitoring plan) Operational Monitoring Continuous monitoring at high frequency for surrogate water quality and/or operational parameters correlated to LRTs Controls for out of compliance Reporting Violations and incidents Routine reporting via format that is simple to review Approval and enforcement by regulatory agency

35 Example to demonstrate application of the framework Hypothetical treatment train for evaluation: Non-potable recycled water to be used for toilet and urinal flushing in a public building 35

36 Steps in the Preliminary Evaluation of DNWS Step Description 1 Identify the Management Category and log 10 reduction targets (LRTs) for the reference pathogen groups using information provided in Chaps. 2 and 3. 2 Evaluate the proposed treatment process to achieve the LRTs using Chapter 4 as a preliminary guide. 3 Designate the requirements for the Responsible Management Entity (RME) using information provided in Chapter 5. 4 Develop a monitoring plan for the proposed non-potable use with information provided in Chapter 6. 5 Develop best management practices for the proposed non-potable use with the information provided in Chapter 7. 36

37 Step 1: Management Category 37

38 Step 1: Rationale for Management Category 3 Non-potable water sources with higher concentrations of pathogens. The larger customer base and increased complexity of the system require a high level of management and responsibility similar to that of public utilities. Non-potable water uses with increased likelihoods of exposure. The risk of exposure is now high due to the number of daily users and the possibility of broader public access to the system. Risk of malfunction also may be higher for more complex treatment mechanisms that require rigorous operation and maintenance. 38

39 Step 1: Log Reduction Targets (Table 3-3) Log 10 Reduction Targets for 10-4 (10-2 ) / person y Benchmarks Water Use Scenario Enteric Virus Parasitic Protozoa Enteric Bacteria Domestic Wastewater or Blackwater Unrestricted irrigation 8.0 (6.0) 7.0 (5.0) 6.0 (4.0) Indoor use 8.5 (6.5) 7.0 (5.0) 6.0 (4.0) Graywater Unrestricted irrigation 5.5 (3.5) 4.5 (2.5) 3.5 (1.5) Indoor use 6.0 (4.0) 4.5 (2.5) 3.5 (1.5) Stormwater (10-1 Dilution) Unrestricted irrigation 5.0 (3.0) 4.5 (2.5) 4.0 (2.0) Indoor use 5.5 (3.5) 5.5 (3.5) 5.0 (3.0) Stormwater (10-3 Dilution) Unrestricted irrigation 3.0 (1.0) 2.5 (0.5) 2.0 (0.0) Indoor use 3.5 (1.5) 3.5 (1.5) 3.0 (1.0) Roof Runoff Water Unrestricted irrigation Not applicable No data 3.5 (1.5) Indoor use Not applicable No data 3.5 (1.5) 39

40 Steps in the Preliminary Evaluation of DNWS Step Description 1 Identify the Management Category and log10 reduction targets (LRTs) for the reference pathogen groups using information provided in Chaps. 2 and 3. 2 Evaluate the proposed treatment process to achieve the LRTs using Chapter 4 as a preliminary guide. 3 Designate the requirements for the Responsible Management Entity (RME) using information provided in Chapter 5. 4 Develop a monitoring plan for the proposed non-potable use with information provided in Chapter 6. 5 Develop best management practices for the proposed non-potable use with the information provided in Chapter 7. 40

41 Step 2: Expected LRVs for unit processes (Chap. 4) Expected log reduction Process step Virus Protozoa Bacteria Report reference Anaerobic reactor Table 4-1 Aerobic packed bed filter Table 4-1 Slow sand filtration Table 4-2 Ozonation >5 0 >4 Tables 4-3 to 4-5 Combined chlorine Tables 4-3 to 4-5 Subtotal >7.5 41

42 Step 2: Assessment of Treatment Train for meeting LRT The treatment train, as proposed, is relatively ineffective against protozoan pathogens. Using information from Chapter 4, one of the following supplemental water treatment processes could be used to meet the LRT: (a) cartridge filtration, 3 micron (3 log 10 reduction protozoa). (b) microfiltration (>4 log 10 reduction of protozoa). (c) UV radiation with a dose of 12 to 13 mj/cm 2 (~3 log 10 inactivation of protozoa). A conservative approach using a UV system with a dose of 40 mj/cm 2 (which accounts for unknowns and uncertainties) is considered adequate for 3 log 10 inactivation of protozoa. Due to high ammonium and other reactive constituents in this wastewater, combined chlorine does not receive log 10 reduction credit. Chlorine is included to control the growth of opportunistic pathogens and biofilms in the recycled water distribution system. 42

43 Steps in the Preliminary Evaluation of DNWS Step Description 1 Identify the Management Category and log10 reduction targets (LRTs) for the reference pathogen groups using information provided in Chaps. 2 and 3. 2 Evaluate the proposed treatment process to achieve the LRTs using Chapter 4 as a preliminary guide. 3 Designate the requirements for the Responsible Management Entity (RME) using information provided in Chapter 5. 4 Develop a monitoring plan for the proposed non-potable use with information provided in Chapter 6. 5 Develop best management practices for the proposed non-potable use with the information provided in Chapter 7. 43

44 Step 3: RME Requirements (Chap. 5) The RME is a prequalified entity with proven capability and experience, and it must have financial security to ensure long-term performance. The regulator licenses the system, reviews periodic reports submitted by the RME, and holds the RME accountable for safe and dependable service. It is the responsibility of the RME to ensure the entire system (i.e., collection, treatment, storage, and distribution) is fully functional, properly maintained, and compliant with treatment requirements at all times. The RME must have the financial and human resource capabilities to handle all repair and replacement needs and must provide emergency response to address any operating problems. The RME also must provide customer service to address questions and complaints. 44

45 Steps in the Preliminary Evaluation of DNWS Step Description 1 Identify the Management Category and log10 reduction targets (LRTs) for the reference pathogen groups using information provided in Chaps. 2 and 3. 2 Evaluate the proposed treatment process to achieve the LRTs using Chapter 4 as a preliminary guide. 3 Designate the requirements for the Responsible Management Entity (RME) using information provided in Chapter 5. 4 Develop a monitoring plan for the proposed non-potable use with information provided in Chapter 6. 5 Develop best management practices for the proposed non-potable use with the information provided in Chapter 7. 45

46 Step 4: Monitoring Plan (Chap. 6) Validation testing. The use of validated technologies or in situ validation study is required for Category 3 systems. Field verification. Challenge testing the PCPs during system commissioning is required for Category 3 systems. During the commissioning phase, the system would be operated offline (i.e., the product/recycled water is discharged to an alternative discharge location). Challenge testing of ozone and UV processes should include the use of suitable surrogates for viruses (bacteriophage) and protozoa (spores of B. subtilis). Continuous verification monitoring. Continuous monitoring of PCPs is required for Category 3 systems. Other parameters for operational monitoring to consider include ph, temperature, electrical conductivity, flow rate, and others associated with individual process operation. 46

47 Step 4: Surrogate Parameters and Control Points (Chap. 6) Surrogate Parameter Control Point Purpose Total chlorine residual Near point-of-use Controls biofouling and the growth of opportunistic pathogens in the distribution system Continuous turbidity Slow sand filter effluent Ensures the integrity of the filtration system Continuous color, ultraviolet light absorbance (UVA), residual ozone, or oxidation-reduction potential Ozonated water Confirms that a sufficient dose of ozone was applied to kill viruses Continuous ultraviolet (UV) intensity and UVA UV-treated water Confirms that a sufficient dose of UV was used to kill protozoa 47

48 Steps in the Preliminary Evaluation of DNWS Step Description 1 Identify the Management Category and log10 reduction targets (LRTs) for the reference pathogen groups using information provided in Chaps. 2 and 3. 2 Evaluate the proposed treatment process to achieve the LRTs using Chapter 4 as a preliminary guide. 3 Designate the requirements for the Responsible Management Entity (RME) using information provided in Chapter 5. 4 Develop a monitoring plan for the proposed non-potable use with information provided in Chapter 6. 5 Develop best management practices for the proposed nonpotable use with the information provided in Chapter 7. 48

49 Step 5: Best Management Practices (Chap. 7) For non-potable water systems, consider the chemical characteristics and biological stability of recycled water, as follows: In systems with high levels of water recycling, an elevated salt concentration is expected. Care should be taken to prevent corrosion or fouling of the water distribution system. If problems develop related to the concentration of salts, then increase the amount of dilution water and blowdown. If the temperature of water in the non-potable water distribution system exceeds 25 C (which is a condition that could promote the growth of opportunistic pathogens like Legionella), then maintain a free chlorine residual of 0.2 mg/l or chloramine residual of 0.5 mg/l at or near the point of use. 49

50 Elements of Project Application Report (PAR) (Chap. 8) Responsible management entity. Water uses. Project overview. Cross-connection control. Relevant regulations. Water quality and log 10 reduction value monitoring. Water source. Facility commissioning plan. Treatment processes. Operation and maintenance plan. Reliability. Provisions for water quality exceedances, power outages, spills, and other emergencies. 50

51 Acknowledgments WE&RF Project Number SIWM10C15 San Francisco Public Utilities Commission Water Research Foundation WateReuse Research Foundation NWRI Panel Members NWRI staff for administering and organizing the Panel s activities Stakeholder Group Public Health Coalition Los Angeles County Department of Public Health New York City Department of Environmental Protection San Francisco Department of Public Health Hawaii State Department of Public Health Oregon Department of Environmental Quality Minnesota Department of Health Washington State Department of Health

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53 Mission of the National Blue Ribbon Commission National Blue Ribbon Commission for Onsite Non-potable Water Systems advances best management practices to support the use of onsite non-potable water systems for individual buildings or at the local scale. We are committed to protecting public health and the environment, and sustainably managing water now and for future generations.

54 Goals of the Commission Serve as a forum for collaboration and knowledge exchange; Research and identify new business opportunities for water utilities in integration and operation of systems; Craft model state policies based on NWRI research report; Research and develop best management practices to support local implementation; and Identify additional research needs in the field.

55 31 Commissioners representing 10 states, DC, and National Partners Chair: Paula Kehoe, San Francisco Public Utilities Scott Abbott, County of Los Angeles Public Health Anita Anderson, Minnesota Department of Health Julienne Bautista, District of Columbia Department of Energy & Environment Brian Bernados, California State Water Resources Control Board Brian Davis, Metropolitan Council, Environmental Services Stephen Deem, Washington State Department of Health Ron Doughten, Oregon Department of Environmental Quality Jon Eaton, City of Eagan, Minnesota Jessica Edwards-Brandt, DC Water Mamdouh El-Aarag, Washington State Department of Health Jay Garland, US Environmental Protection Agency Bertha Goldenberg, Miami-Dade Water and Sewer Department Brian Good, Denver Water

56 31 Commissioners representing 10 states, DC, and National Partners Charles Graf, Arizona Department of Environmental Quality Bret Icenogle, Colorado Department of Public Health and Environment Mark Jaeger, Seattle Public Utilities Vlada Kenniff, New York City Department of Environmental Protection Sina Pruder, Hawaii State Department of Public Health Wastewater Branch Melinda Rho, Los Angeles Department of Water and Power Genevieve Salmonson, Hawaii State Department of Public Health Neal Shapiro, City of Santa Monica, California Robert Stefani, Austin Water Utility Wing Tam, LA Sanitation, City of Los Angeles Jacqueline Taylor, County of Los Angeles Public Health Barry Usagawa, Honolulu Board of Water Supply Chris Wanner, Portland Water Bureau June Weintraub, San Francisco Department of Public Health Radhika Fox, US Water Alliance National Partner Melissa Meeker, Water Environment & Reuse Foundation National Partner Rob Renner, Water Research Foundation- National Partner

57 National Blue Ribbon Commission Guiding Principles Protect public health Develop policies driven by risk-based science and research Utilize a consensus-based approach Integrate best practices Honor local context Commit to continuous learning

58 National Blue Ribbon Commission Research Outputs Model state guidance and policies for the management and oversight of onsite non-potable water systems based on research; Model federal guidance for best management practices to support local implementation of onsite non-potable water systems; Research and highlight new business opportunities for water utilities in the design, development, integration, and operation of onsite non-potable water systems; and Inventory of research needs in the field of onsite non-potable water systems.

59 Benefits of National Blue Ribbon Commission Research has broad application to many utilities seeking to implement oversight and management programs on the local level Provides model ordinances/policies based on scientific research and new business opportunities for utilities integrating decentralized and centralized water systems based on research Establishes uniform best management practices across the country Reduces the time needed to conduct research and establish practices Creates a network of practitioners to assist and mentor utilities Offers an approach to communities implementing One Water management strategies

60 Type Your Questions into the Chat Box Paula Kehoe Sybil Sharvelle Harold Leverenz Katy Lackey 60

61 Risk-Based Framework for the Development of Public Health Guidance for Decentralized Non-Potable Water Systems (WE&RF Project No. SIWM10C15) Available for FREE*: tid=siwm10c15 *WE&RF login required. Create one for free at: 61