DALLAS PROACTIVE PIPELINE ASSESSMENT PROGRAM SAVES MILLIONS OF GALLONS OF WATER AND PREVENTS CATASTROPHIC PIPELINE FAILURES

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1 DALLAS PROACTIVE PIPELINE ASSESSMENT PROGRAM SAVES MILLIONS OF GALLONS OF WATER AND PREVENTS CATASTROPHIC PIPELINE FAILURES RANDY PAYTON, ASSISTANT DIRECTOR CITY OF DALLAS WATER UTILITIES OCTOBER 28, 2015

2 TODAY S TOPIC 1. DRIVERS FOR DALLAS PIPELINE ASSESSMENT PROGRAM 2. THREE PRONG APPROACH - LEAK DETECTION & REPAIR - CONDITION ASSESSMENT & REPAIR - PIPELINE REPLACEMENT 3. RESULTS & ACCOMPLISHMENTS SaveDallasWater.com

3 DALLAS WATER UTILITIES (DWU) - FOUNDED IN FUNDED FROM WATER AND WASTEWATER REVENUES - 1,500 EMPLOYEES MILLION POPULATION SERVED MILLION - DALLAS MILLION IN 27 WHOLESALE CUSTOMER CITIES SQUARE MILE SERVICE AREA - 100% SURFACE WATER

4 DWU S SYSTEM - 7 RESERVOIRS, (6 CONNECTED AND 1 CURRENTLY NOT CONNECTED) - 4,926 MILES OF WATER MAINS, EXCLUDES SERVICE LINES - 4,260 MILES OF WW MAINS - 3 WATER TREATMENT PLANTS - COMBINED CAPACITY OF 900 MGD - 23 PUMP STATIONS - 9 ELEVATED AND 12 GROUND STORAGE TANKS - SYSTEM OPERATING PRESSURE ~70 PSI

5 DRIVERS FOR DWU S PIPELINE ASSESSMENT PROGRAM 1. SERVICE RELIABILITY (LARGE, CRITICAL PIPELINES) 2. REDUCE WATER MAIN LEAKS (WATER LOSS, LEAKS ESCALATE TO BREAKS) 3. MEET GOALS FOR TEXAS 5-YEAR WATER CONSERVATION PLAN 4. PUBLIC PERCEPTION/WATER RESTRICTIONS 5. PRUDENT MANAGEMENT OF FINANCIAL RESOURCE WELL-RUN UTILITIES MAINTAIN THEIR INFRASTRUCTURE THROUGH PROPER LEVELS OF INSPECTION, REPAIR & REPLACEMENT

6 DWU INVENTORY US Water Transmission & Distribution System Inventory Ductile Iron, 22% Steel, 4% PCCP, 3% DWU Inventory (4,926 miles) Ductile Iron, 18% Steel, <1% PCCP/ BWP, 12% Cast Iron, 40% PVC, 13% AC, 16% Cast Iron, 40% PVC, 24% Other, 3% US EPA State of Technology Report (2009) Other, 5% AC, <1%

7 THREE PRONG APPROACH Leak Detection & Repair - Small and Large diameter Condition Assessment -Risk based approach Pipeline Replacement - 1.4% per year goal

8 DWU LEAK DETECTION PROGRAM FY2005 FY2006 FY2009 FY2010 FY2016 +$360K +(4) Staff +Equipment 10 Year Cycle +$50K +Equipment +(4) Reallocated Staff 5 Year Cycle +$652K +(6) Staff +Equipment 2.5 Year Cycle +$150K +(2) Staff Correlation + Equipment Reduced Life of Leak +$200K Large Diameter Program Increased Miles of Larger Diameter Pipe Annually Total Miles Surveyed miles 4,828 miles FY05 FY06 FY07 FY08 FY09 FY10 FY11 FY12 FY13 FY14 FY Total Leaks Total Miles Surveyed

9 SMALL DIAMETER LEAK DETECTION IN-HOUSE Leak Survey Localize with Correlators Pinpoint 14 dedicated staff (5 crews) Entire system every 2.5 years Focused on 18 diameter and smaller ~17 miles/day

10 SMALL DIAMETER - NUMBER OF LEAKS PER MILE INSPECTED Average miles per month surveyed

11 3.5 BILLION GALLONS SAVED SINCE ,000 3,500 Millions of Gallons of Treated Water Saved Non-Revenue Water 7.0% 3,493 Million Gallons 3,000 2,500 2,000 1,500 1, Non-Revenue Water 11.0% Larger leaks found in recent years ,617 FY07 FY08 FY09 FY10 FY11 FY12 FY13 FY14 FY15

12 LARGE DIAMETER LEAK ASSESSMENT INTERNALLY & OUTSOURCED CHALLENGES WITH LARGE DIAMETER SERVICES EMPLOYED SAHARA I&II SMARTBALL TECHNOLOGIES UNDER REVIEW PILOT W/ECHOLOGICS - ECHOLIFE

13 WESTMORELAND RD. PIPELINE LEAK AUG INCH DIAMETER DUCTILE IRON (1981) 34 YEARS OF AGE 15 FEET OF COVER (CAVITY) DOT-ROW ACCESS POINTS >1,000 LF 1 LEAK NON-SURFACING ESTIMATED 1,700 GPM/2.4 MGD

14 GREENVILLE PUMP STATION PIPELINE SAHARA - TETHERED LEAK DETECTION METHOD 24-INCH DIAMETER CAST IRON (1952) 63 YEARS OF AGE 8 FEET OF COVER - ADJACENT TO TRIBUTARY ACCESS POINTS PUMP STATION 250 LF SOUTH 1 LEAK NON-SURFACING ESTIMATED 1,200 GPM/1.7 MGD

15 SUMMER LARGE DIAMETER ACCOMPLISHMENTS 19 DAY PROJECT SAHARA TECHNOLOGY ASSESSED 10 MILES OF PIPELINE VARIETY OF DIAMETERS AVERAGE AGE 56 YRS Barrel Leak on 16 Cast Iron IDENTIFIED 15 LEAKS 1.5 LEAKS PER/MILE TOTAL WATER SAVINGS ESTIMATED 4.8MGD Joint Leak on 24 Cast Iron

16 LARGE DIAMETER PROGRAM Leaks Per Mile with Inline Tethered System Annual Average of 1.3 Leaks Per MIle

17 FY15 LEAK DETECTION PROGRAM ACCOMPLISHMENTS DWU SPENT $150K MONTHLY ON LEAK DETECTION PROGRAM PROGRAM RECOVERED AN ESTIMATED 14.2 MGD PRODUCTION AND DELIVERY RECOVERY - DAILY - $12K - MONTHLY $360K UNKNOWN IMPACTS AND SAVINGS - POTENTIAL PUBLIC SAFETY ISSUES - PRIVATE PROPERTY AND ROAD DAMAGE - INTERRUPTION TO SCHOOL OR HOSPITAL $?

18 CONDITION ASSESSMENT ON LARGE DIAMETER Retirement Center DART Rail System 84-inch 130,000 GPM Intersection Downstream

19 DWU S APPROACH TO CONDITION ASSESSMENT 36 TO 108-INCH DIAMETERS Pressure and Transient Monitoring Smartball Leak and Air Pocket Electromagnetic Inspection Distressed Wires FEA PROBABILITY OF FAILURE

20 RISK BASED APPROACH COF X POF = RISK CONSEQUENCE OF FAILURE GEOGRAPHIC LOCATION PIPE DIAMETER/WATER LOSS UTILITY/OPERATIONAL IMPACTS PROBABILITY OF FAILURE AGE OPERATING PRESSURE PIPE CONDITION/INSPECTION RESULTS SOIL CONDITIONS POTENTIAL STRAY CURRENTS LAST INSPECTION Geographic Location 0 Rural land with no aboveground structures 1 Potential for light damage/flooding to private property 3 Potential heavy flooding and damage to private property 5 Major Flooding and Damage to private property Pipe Diameter/Water Loss 1 48-inch or less 3 54" to 66" 5 72" to 84" 8 96" or greater Utility/Operational Impacts 0 No Service Interruption 1 Service Interruption to area residential and commercial (more than 24 hours) 3 Interruption to Wholesale Customer City 5 Water Restriction during Peak and/or Non-Peak Demand Pipe Characteristics 1 per 10 Yrs Age of Pipeline (10% of Total Age) 1 per 10 PSI Average Operating Pressure (10% of Average PSI) Pipe Condition (Visual & Wire Breaks) ( Rating of % overall distress, Rating of to 1.0 overall 1 to 5 distress, Rating of 5-1.1% or greater overall distress or internal dilapidation) Pipe Environment 1 to 3 Soil Conditions (1 - Rock, 2 -Sandy Loam, 3 -Clay) 0 to 3 AC/DC Stray Current Risks -(Rating of 0 for No, 3 for YES, High Voltage Electrical Transmission or Rail Crossing/Parallel Pipeline) Last Inspection 1 Less than 6 years ago Years ago Years ago 4 Never

21 CURRENT 10 YEAR SCHEDULE Tentative Inspection Year Pipeline Inspection Schedule Pipe Name Pipeline Diameter (inches) Risk Pipeline Material System Type of Inspection(s) Comments/Concerns 2013 I35 36 Medium PCCP Potable EM, Sahara Completed 2013 Jim MIller 96 Very High PCCP Potable EM, Smartball Completed 2014 Tawakoni 84 High PCCP Raw EM, Smartball Completed 2014 Hampton/Camp Wisdom 60 High PCCP Potable EM, Cathodic Completed 2014 Houston School Road 66 Very High PCCP Potable EM, Cathodic Completed 2015 Whiterock 84 Very High PCCP Potable EM, Smartball Partially Completed 2015 Samuel 90 Very High PCCP Potable EM, Cathodic Completed 2015 Danieldale 54 High PCCP Potable EM, Cathodic Completed 2016 Forney Raw 96 High PCCP Raw EM, Smartball 2017 Lake June 90 Very High PCCP Potable EM, Sahara 2017 Whiterock 84 Very High PCCP Potable AFO 2018 Denton 54 Very High Bar Wrapped Special Potable EM, Smartball 2018 Denton 66 Very High Bar Wrapped Special Potable EM, Smartball 2018 Tawakoni 72 High PCCP Raw EM, SMartball 2019 Jim Miller 96 Very High PCCP Potable EM, Smartball 2020 Lake June 90 Very High PCCP Potable EM, Smartball 2021 Lamar 60/66 High PCCP Potable EM, Sahara 2022 Simpson Stuart 72 Very High PCCP Potable EM, Sahara 2023 Cedar Crest 96 High PCCP Potable EM, SMartball TBD Lake Fork 108 Medium PCCP Raw EM, SMartball

22 DWU S LARGE DIAMETER PIPELINES 96% of pipe is in good shape DWU has inspected 433 miles of large diameter mains (68,289 pipes) of which 3.4% has some distress

23 JIM MILLER PROJECT - 96-INCH DIAMETER PCCP - INSTALLED 1980 (35 YRS OLD) - MULTIPLE CROSSINGS HIGHWAYS/RAILROAD - TRAVELS THRU TWO NEIGHBORING CITIES - ORIGINALLY INSPECTED - FY05 - SECOND INSPECTION - FY miles (3,194 pipes)

24 PIPELINE REPLACEMENT PROGRAM DALLAS HAS AN AGGRESSIVE PIPELINE REPLACEMENT PROGRAM EFFICIENCY STUDY GOAL WAS SET TO REPLACE 50% OF WATER DISTRIBUTION SYSTEM IN NEXT 30 YEARS TO ACHIEVE A 70 YEAR REPLACEMENT CYCLE (AVERAGING 1.4% PER YEAR) PIPELINES ARE REPLACED BASED ON PARAMETERS INCLUDING: PROBABILITY OF FAILURE, CONSEQUENCE OF FAILURE, WATER QUALITY, BREAK FREQUENCY, SOIL, ETC. EFFECTIVE DESIGN AND CONSTRUCTION PRACTICES Years since first break

25 EFFECTIVE PRACTICES GREATER EVALUATION AND SELECTION OF PIPE MATERIALS IDENTIFY AND RESTRICT INFERIOR PRODUCTS INCREASED USE OF PVC IMPROVED DESIGN PROCESS LOOPED DESIGN OR AUTO-FLUSHERS LESS FITTINGS AND CONNECTIONS ACCESS POINTS FOR FUTURE LEAK/CONDITION ASSESSMENT HYDROSTATIC TESTING ZERO ALLOWABLE LEAKAGE

26 ACHIEVEMENTS WITH REPLACEMENT PROGRAM - MAINTAINED AVERAGE REPLACEMENT OF >1 % ANNUALLY - 20% REDUCTION IN ANNUAL PIPELINE REPAIRS - PERCENT OF SYSTEM OLDER THAN 50 YEARS HAS BEEN REDUCED FROM 48% TO 41% - MAIN BREAKS PER MILE DECREASED FROM 0.6 TO 0.3 Estimated Cumulative Water Loss of 30 BG

27 CONCLUSIONS THREE PRONG APPROACH 1. LEAK DETECTION & REPAIR PROGRAM* - WATER SAVINGS APPROACHING 3.5B GALLONS - REDUCTION OF NRW - 11% TO 7% - REDUCTION IN CATASTROPHIC FAILURES 2. CONDITION ASSESSMENT & REPAIR - EFFECTIVELY MANAGING PIPELINES AT A FRACTION OF REPLACEMENT COST - PREVENTING CATASTROPHIC FAILURES 3. PIPELINE REPLACEMENT PROGRAM - MAIN LEAKS/BREAKS PER MILE REDUCED 0.6 TO DECLINE IN TOTAL MAIN REPAIRS *LEAK PROGRAM COSTS $1.67 PER 1,000 GAL SAVED VS $2.00 PER 1,000 GAL FOR NEW WATER SOURCES

28 QUESTIONS