Guide for the Preservation of Highway Tunnel Systems (2015)

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106 a p p e n d i x c Highway Tunnel Preservation Prioritization Flowchart Perform Tunnel Systems Evaluation and Develop List of Tunnel Preservation Actions for Each Tunnel Identify Agency Level-of-Service (LOS) Categories Cost-EffectivenessDetermine the Asset’s Remaining Life as a Result of the Preservation Action Develop Life-Cycle Costs for Each Preservation Action – Capital Cost, Annual Change in Energy Cost, Annual Change in Maintenance Cost Develop LOS Priorities by Assigning a Weight to Each LOS (Sum of Weights Equals 100%) LOS Score Evaluate Impact of Preservation Actions on Agency LOS – Rate Each on a Scale of 1 to 5 Multiply the LOS Weight (%) by the Rating (1 to 5); Sum and Divide by 5 to Obtain the LOS Score Obtain the Average Daily Traffic for Each Tunnel

Highway Tunnel preservation prioritization Flowchart 107 Risk-Based Urgency Score Cost-Effectiveness Calculate the Annualized Life-Cycle Cost, ALCC [ALCC = C * (i*(1+i)n)/((1+i)n-1) – A, where C = Initial Cost, $ i = Discount Rate, % n = Remaining Life Resulting from Improvement, years A = Annual Change in Energy and Maintenance Costs, $ Calculate Cost-Effectiveness Score CE = 100, if 100 / [(ALCC/ADT)*F] > 100, otherwise CE = 100 / [(ALCC/ADT)*F], where CE = Cost-Effectiveness Score ADT = Average Daily Traffic, number of vehicles ALCC/ADT = Annual Life-Cycle Cost per Daily Vehicle F = Cost Factor Determine the Theoretical Service Life of the Asset Calculate the % of Life Expended Evaluate the Current Condition of Asset (Without Preservation Action) Denote if Preservation Action is Driven by a Regulatory Requirement Evaluate Urgency; Assign a Risk-Based Urgency (RBU) Rating (1 to 10); Multiply by 10 to Obtain RBU Score Determine the Remaining Life for the Existing Assets (Without Preservation Action) – If the Asset Does Not Currently Exist, Remaining Life = N/A Evaluate the Risk of Unplanned Events Calculate the Present Value of the Life-Cycle Cost, PV [PV = (Annual Change in Energy + Maintenance Costs)/(1+i)n, where i = Discount Rate, % n = Remaining Life Due to Preservation Action, years]

108 Guide for the preservation of Highway Tunnel Systems Staffing and Funding Needs Escalate Material and Labor Costs Based on Implementation Year Calculate Total Project Cost Evaluate Prioritization Relative to Funding Evaluate Staffing Needs Based on Prioritized Program Estimate Agency Labor as a % of Total Labor Cost Calculate Labor Costs for Agency and Contractor Calculate Material Costs Identify Year that Preservation Action Will Be Implemented Based on Prioritization Estimate Labor as a % of Total Cost Overall Measure of Effectiveness Combine LOS Score, CE Score, and RBU Score to Obtain Overall Measure of Effectiveness (MOE) Develop Weights for Each Score – LOS, CE, and RBU Prioritization Determine Agency Prioritization (Adjust Calculation Prioritization Due to Operational, Political, and Other Constraints) Sort Preservation Actions by Overall Measure of Effectiveness (Highest to Lowest)