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Best for the Buck: Using Asset Management for Project Design at Highline Water District. Matthew J. Maring, P.E. April 30, 2008. Initial Project Design Concept. Transmission Capacity Improvements 4600’ 16” Diameter Mains $1.8M Estimated Capital Cost Dead-End Main Looping Improvements
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Best for the Buck:Using Asset Management for Project Design atHighline Water District Matthew J. Maring, P.E. April 30, 2008
Initial Project Design Concept • Transmission Capacity Improvements • 4600’ 16” Diameter Mains • $1.8M Estimated Capital Cost • Dead-End Main Looping Improvements • 6500’ 8” Diameter Mains • $2.1M Estimated Capital Cost • New Pressure Zone Creation • 7 PRVs and 12 Isolation Valves • $0.8M Estimated Capital Cost • $4.7M Total Estimated Capital Cost
Project Approach • Asset Management Predesign Review • Business Case Evaluation • Hydraulic Modeling Analysis • Alternative Design Approaches • Identify, Optimize, Assess, Compare • Identify Preferred Design Alternatives • Detailed Design • Construction
Business Case Evaluation Process • Form Expert Team – Highline and BC Staff • Problem and Level of Service Definition • Data Collection, Problem Characterization • Alternative Development Brainstorming • Alternative Performance Evaluations • Hydraulic Modeling Analysis • Alternative Performance, Cost, and Risk Comparison • Preferred Solutions Detailed Design
Business Case Difference • Lifecycle Cost – A dollar is a dollar • Capital, O&M, R&R, Risk Costs • Triple Bottom Line Costing • Financial • Community/Social • Environmental • Preferred Solution = Lowest Lifecycle Cost that Meets Level of Service • Decisions • Documented, Defensible, Transparent
Problem Definition • Low Pressures • Limited Fire Flow Availability • Dead-End Mains • Water Circulation and Turn Over • Low Pressures, Limited Fire Flow • High Pressures • Frequent Main Breaks
Level of Service • Peak Hour Demand Pressures > 30-40 psi • Max Day Demand + Fire Flow > 20 psi • Dead-End Mains • Address Pressures and Fire Flows • Correct where Financially Preferable • High Pressures and Main Breaks • Distribution Leakage Standards • Correct where Financially Preferable • Goal: Max Static Pressures < 100 psi
Data Collection and Problem Characterization • Hydraulic Model System Performance • Minimum Pressures, Fire Flows • Water Main Breaks • 3 to 4 Times More Frequent in High Pressure Areas • $6K+ Average Cost per Break • Repair Labor, Materials, Equipment • Lost Water, Insurance Claims/Deductibles • Reduce High Pressure Breaks to “Normal” Levels = $18K Annual Savings • Dead-End Main Flushing is “Cheap”
Existing System: Future Model Scenario Pressure and Fire Flow Performance
Alternative Development • Low Pressures and Fire Flow Availability • Pipe and Pump Improvements • Various Sizes and Combinations • Dead-End Mains • Looping • Alternating and Continuous • High Pressures • New Pressure Zone • PRV Quantity and Locations • Isolation Valve Quantity and Locations
Alternative Performance New Zone Area Pressures, Before and After
Lifecycle NPV Cost Comparison • Lifecycle Net Present Value (NPV) Analysis • Capital, O&M, R&R, Risk Costs • Amount Invested Today to Fund All Current and Future Asset Costs
Risk Cost Considerations • Risk Cost = (Probability) x (Consequence) • Example A:(Annual Number of Main Breaks) x (Average Break Repair Cost) • Example B:(Likelihood of Insurance Claim) x (Insurance Deductible + Staff Costs) • Benefit Cost = (Probability) x (Avoided Consequence) • Example C:(Avoided Number of Main Breaks) x (Average Break Repair Cost)
Preferred Solution for Detailed Design • Transmission Capacity Improvements • 1800’ 12” Diameter Mains • Pump Station Upgrades • $1.1M Estimated Capital Cost • Dead-End Main Looping Improvements • 2700’ 8” Diameter Mains (Alternating) • $0.9M Estimated Capital Cost • New Pressure Zone Creation • 3 PRVs, 50 psi Pressure Reduction • $0.3M Estimated Capital Cost • $2.3M Total Estimated Capital Cost
Preferred Solution Delivers Optimal Performance and Cost Savings
Avoided Risk Costs Demonstrate Project Value • High Pressure Areas Main Breaks • $0.5M Lifecycle NPV Repair Cost • New Pressure Zone Creation • $0.4M Lifecycle NPV Cost • $0.5M Lifecycle NPV Avoided Repairs • $0.1M Savings Over Status Quo
Asset Management Approach Successful Business Case Evaluation and Hydraulic Modeling Analysis Approach Results: • Cost Savings • $2.6M Capital Costs = 53% • $2.3M Lifecycle Costs = 45% • Higher Overall Level of Service • Takes Advantage of Existing Assets • Pump Station Upgrades vs. New Water Mains • New Pressure Zone Pays for Itself • $0.4M Lifecycle Cost vs. • $0.5M Avoided Lifecycle Main Break Repair Costs