Regional Service Through Unity… Meeting our Region’s Needs Today and Tomorrow NTMWD BOARD MEETING January 24, 2019
The Pledge of Allegiance to the Flag of the United States of America "I pledge allegiance to the Flag of the United States of America, and to the Republic for which it stands, one Nation under God, indivisible, with liberty and justice for all." The Pledge of Allegiance to the Texas State Flag "Honor the Texas flag; I pledge allegiance to thee, Texas, one state under God, one and indivisible."
CLICK TO EDIT MASTER TITLE STYLE 2018 FREE CHLORINE MAINTENANCE PERIOD EXPERIENCE 2018 free chlorine maintenance period generated more interest than ever before • Coordinated with members/customers as in previous years • Continued pushing proactive monthly water quality information to NTMWD webpage as in prior years • Pushed early public notices to internet/members & customers/media • Significant interest generated by activist group spurring formation of local interest group • NTMWD responded swiftly to questions raised by and in the public • Anticipate some questions will surface again in 2019
CLICK TO EDIT MASTER TITLE STYLE OVERVIEW OF RECENT WATER QUALITY EVENTS TCEQ Investigation and Findings • Received 281 citizen complaints during March 2018 • Taste and odor • Irritation of skin, eyes, nose, etc. • Respiratory and gastrointestinal issues • TCEQ collected 117 water quality samples in NTMWD and city distribution systems during March • Results of investigation received in May 2018: • NTMWD had no violations • Chlorine and ammonia concentrations measured in water quality samples not expected to cause adverse health effects • Chlorine and chloramine concentrations may have contributed to observation of odors
Purpose & Introductions EVALUATIONS AND STUDIES Developed three scopes of work: • CDM Smith ― Water quality data review (2015-2018) ― Comprehensive look at transmission system quality program • Carollo ― BAF implementation schedule and outcomes ― Technical feasibility and costs of GAC • FNI ― Water quality sampling program ― Supplemental disinfection feasibility and costs ― Best practices document for cities (Please refer to Ad Memo No. 5186, 5187, 5188)
Purpose & Introductions SUMMARY OF KEY FINDINGS GAC Analysis: • Full filter conversion is not feasible • Implementing post filtration contactors would likely result in 35-45% increase in water rates BAF Analysis: • Identified potential for phasing-in BAF at Plants III and IV • However, it is not possible to significantly accelerate conversion to BAF Enhanced Sampling & Residual Adjustment Analysis: • Potential for additional online monitoring in transmission system • Recommended maintaining current chloramine operations
Purpose & Introductions 2018 MAINTENANCE PERIOD DATA REVIEW Summary of data review: • Some chemical doses at the plant varied, but finished water quality in 2018 was comparable to previous years • Chlorine residuals leaving Wylie WTP were very similar to previous years, but slightly higher residuals were noted in some delivery reservoirs • Rainfall event at beginning of maintenance period temporarily reduced demand • Difference between free and total residual chlorine indicates probable speciation, which can impact taste and odor • Findings consistent with TCEQ report
Purpose & Introductions 2018 MAINTENANCE PERIOD DATA REVIEW Theory regarding 2018 free chlorine maintenance period complaints • Breakpoint chlorination resulting in the formation of dichloramine and trichloramine species • Di- and trichloramine can create taste and odor issues at low levels • The interface of the free chlorine and chloraminated waters is where the highest potential for speciation and resultant taste/odor issues occur
CLICK TO EDIT MASTER TITLE STYLE 2019 FREE CHLORINE LOOK AHEAD NTMWD is working in coordination with cities to minimize taste and odor, and provide additional information to the public: • Have incorporated information from studies into new PR materials • Conducting additional water quality monitoring, providing technical resources and coordinating operations with cities: - Best practices document - Minimizing system storage volumes - Monitoring free chlorine transition front - Additional disinfection byproduct sampling
Best Practices During The Temporary Change In Disinfectant NTMWD BMP Activities Customer Activity Suggestions • Move the transition interface • Follow best practices guide through the system quickly • Move the disinfectant transition through quickly • Reduce Wylie Complex storage – Modify tank levels as appropriate in your distribution system to reduce storage • Suggest temporarily operating – Cycle tanks aggressively tank levels at the low levels as – Flushing activities to assist in moving water appropriate to meet system • Monitor the disinfectant transition in capacities your system – Will want verification from cities to – Measure Total, Free and Mono chloramine do this with field kits • Aggressively cycle tanks as appropriate • Monitor disinfectant transition in transmission system
Best Practices Suggestion – Minimize System Storage Volumes Minimizing storage volumes helps mitigate the formation of Meet system demands odorous di- and trichloramines and emergency fire flows. Wylie Complex: • Minimize storage volumes in clearwells • Low level operation results in 12 MG reduction Transmission System: • Coordinate with cities to temporarily reduce storage volumes at delivery points
TRANSMISSION SYSTEM MONITORING Storage Tank Avg. Water Temporary Change in Disinfectant Age (Days) <1 Wylie WTPs Track free chlorine front: <1 East Fork #2 • 11 locations will be monitored for <1 Rockwall #1 the first week of conversion 1-3 - Total chlorine, free chlorine, Shiloh monochloramine 1-3 Plano #2 1-3 McKinney #1 • Use hydraulic water age model in 1-3 conjunction with sampling data to Garland # 4 coordinate with cities 1-3 Farmersville - Email sent 2x daily 1-3 McKinney/Frisco PS 3-5 Princeton #1 7 Forney #1
CLICK TO EDIT MASTER TITLE STYLE TRANSMISSION SYSTEM MONITORING • Began collecting monthly disinfection byproduct data in late 2018 and will sample during temporary change • Working to enhance ability to monitor water quality in the transmission system by installing online water quality instrumentation: • Currently have 6 instruments online measuring total chlorine every 5 minutes • Another 16 instruments capable of monitoring chlorine and ammonia will be installed by early 2020 • Additional online instruments identified as part of FNI recommendations for enhanced water quality monitoring
CLICK TO EDIT MASTER TITLE STYLE COMMUNICATIONS TIMELINE Communications for Temporary Change in Disinfectant, March 4 – April 1 Date Activity Jan. 16 Review with city communicators, receive final feedback Jan. 21 New web pages on NTMWD.com with updated messages, materials posted online Jan. 24 Communicate plans, provide packet of materials to Board of Directors Jan. 28 Tom to present info to Member City Managers at monthly breakfast (provide packets and extra copies of fact sheets for Council members) Jan. 31 News release for 30-day notice requirement Week of Feb. 4 Media briefings for local community newspapers Feb. 5 (1:30 pm) Tour/briefing for County Health agency reps (asking to inform health providers) Notify local legislative staff Include notification and link to online info in News Stream eNewsletter Cities arm utility billing specialists/call center reps with info
CLICK TO EDIT MASTER TITLE STYLE COMMUNICATIONS TIMELINE Communications for Temporary Change in Disinfectant, March 4 – April 1 Date Activity Feb. 15 Water Treatment Plant tour, briefing for city officials (focus on water quality) – PLEASE HELP ENCOURAGE PARTICIPATION even if they’ve been before Feb. 25 Second news advisory reminder – one week before start March Post test results online for chlorine levels: daily average from plant, (ongoing) weekly delivery points, plus DBP monthly data (starting with last December) Respond to emails, calls, social media comments, media questions (asking for city assistance) Third-party support: – TCEQ report from last year posted online – TCU Professor Becky Johnson (confirm, support process) – County Health Agency Reps (for medical questions) – Toxicologist Dr. Scott Phillips (videos addressing common medical concerns)
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