2 Life-Cycle Cost Analysis Required by National Highway System (NHS) Designation Act of 1995Removed by Transportation Equity Act of the 21st Century (TEA-21) of 1998FHWA still encourages LCCANational Highway System Designation Act of 1995The legislation designates the National Highway System (NHS), developed by the Department of Transportation (DOT) in cooperation with the states, local officials, and metropolitan planning organizations (MPOs). DOT proposed the system to Congress on Dec. 9, 1993, as required by the Intermodal Surface Transportation Efficiency Act of 1991 (ISTEA). The system approved by Congress reflects modifications agreed upon by DOT and Congress as of Nov. 13, The total mileage is about 260,000 kilometers (160,955 miles) and includes the Interstate Highway System, as well as other roads important to the nation's economy, defense, and mobility. ISTEA set a deadline of Sept. 30, 1995, for Congress to establish the system. Until the system was designated, the law prevented future NHS and Interstate Maintenance (IM) funds from being released to the states. With the enactment of the NHS legislation, the $5.4 billion of fiscal year (FY) 1996 funds were distributed to the states. (From Public Roads, Spring 1996, v.49, No. 4).
3 Life-Cycle Cost Analysis PurposeDetermine total cost or value of an item over its entire life-cycleDecision support toolLegislatively defined:“. . . a process for evaluating the total economic worth of a usable project segment by analyzing initial costs and discounted future cost, such as maintenance, user, reconstruction, rehabilitation, restoring, and resurfacing costs, over the life of the project segment.” A usable project segment is defined as a portion of a highway that, when completed, could be opened to traffic independent of some larger overall project.
4 General Procedure Initial strategy & analysis decisions Analysis period (at least 35 years)Alternative pavement design strategiesPavement performance over timeMaintenance/rehabilitation timing
5 General Procedure Agency costs Preliminary engineering Contract administrationInitial constructionConstruction supervisionMaintenanceRehabilitationAdministrativeSalvage value
6 General Procedure User costs Normal operation Work zone Types of user costsVehicle operatingUser delaycrash
7 VOC: The Cost or Roughness Papagiannakis and Delwar (2001) 1 m/km = $200/yr for maint. & repair = 1.7 cents/mileBarnes and Langworthy (2003)IRI (inches/mile)% VOC Increase170 +25%14015%1055%800%Barnes, G. and Langworthy, P. (2003). The Per-Mile Costs of Operating Automobiles and Trucks. Report No. Mn/DOTPapagiannakis, T. and Delwar, M. (2001). Computer model for life-cycle cost analysis of roadway pavements. Journal of computing in civil engineering, Vol. 15, No. 2, pp
8 VOC Assuming IRI = 80 inches/mile 56.1 cents/mile25.2 cents/mile18.3 cents/mileData from Barnes and Langworthy (2003)
9 VOC Assuming IRI = 140 inches/mile 64.5 cents/mile31.3 cents/mile24.0 cents/mileData from Barnes and Langworthy (2003)
10 VOC Assuming IRI = 170 inches/mile 70.1 cents/mile34.0 cents/mile26.1 cents/mileData from Barnes and Langworthy (2003)
12 General Procedure Alternative comparison Net present value (NPV) Equivalent uniform annual costs (EUAC)i=discount ratenyear of expenditurePresent value (PV) factori=discount ratenAnalysis period (the number of years into the future over which you wish to compare projects)
13 General Procedure Analyze results Sensitivity analysis Probability (or “risk”) analysis
14 What is NOT Considered Environmental impacts Equity impacts Energy use EmissionsWasteEquity impactsConnectivityCongestionCommunityLCA of the CEE 404 Final Project Options (from Weiland 2008)30-40% waste is typical – most is from manufacturing and end-of-life disposal (assumptions can be debatable)
15 What is NOT Considered Environmental impacts Equity impacts Energy use EmissionsWasteEquity impactsConnectivityCongestionCommunityLCA of the CEE 404 Final Project Options (from Weiland, 2008)30-40% waste is typical – most is from manufacturing and end-of-life disposal (assumptions can be debatable)
16 General Assumptions Both pavements built at same time Same traffic on each pavementSame user costs between construction activitiesVOC is the sameImplies road roughness is the sameMaintenance/rehabilitation activities are scheduled such that user costs are the sameImplies some unlikely activities must be scheduledDifferences will be in…Construction costsUser delay costs during constructionSalvage value
17 Be Careful of Assumptions SR 704, Cross-Base Highway ProjectEstimated Cost$318 millionCurrent Funding$43 million
19 Be Careful of Assumptions SR 704: HMA Alternative
20 Be Careful of Assumptions SR 704: PCC Alternative
21 Other Life-Cycle Cost Study Pitfalls Not accounting for user costsTraffic delay during constructionVOC due to differing roughnessDifferences in salvage valueMaintenance/rehabilitation timingSee APA synthesis by Villacres (February 2005): Pavement Life-Cycle Cost Studies Using Actual Cost DataThese items are often not appropriately accounted for because studies tend to look at actual historical costs. These costs usually don’t involve user costs and almost certainly do not account for maintenance and rehabilitation practices that would result in users incurring comparable VOC between pavement sections .
22 I-71 in Ohio: Present Worth in 1960 of Total Contract Costs (using a 5% discount rate) Commissioned by Flexible Pavements of OhioDid not account for user costsFrom Gibboney. (1995). Flexible and Rigid Pavement Costs on the Ohio Interstate Highway System
23 I-70 in Kansas: Total Costs per 4-Lane Mile in 2001 Dollars Did not account for user costsDid not account for KDOT maintenance work (negligible)From Cross and Parsons. (2002). Evaluation of Expenditures on Rural Interstate Pavements in Kansas
24 I-80, Iowa County, Iowa: Total Cumulative (Life-Cycle) Costs Did not account for user costsDid not account for routine maintenance costsDid not account for salvage valuesFrom Asphalt Paving Association of Iowa. (1998). Iowa Interstates: A Look at Performance and Costs
25 40-Year Life-Cycle Cost Analysis Commissioned by the Portland Cement AssociationDid not account for user costs?From Waalks. (n.d.). Life Cycle Cost Analysis: A Guide for Comparing Alternative Pavement Designs
26 Michigan: Average Overall Cost per Lane-km per Year From Waalks. (n.d.). Life Cycle Cost Analysis: A Guide for Comparing Alternative Pavement Designs
27 WSDOT Interstate Pavements time to first rehabilitation
28 ODOT Interstate Pavements time to first rehabilitation
32 Issues to Address Pavement design Life cycle Engineering Will foundation support PCC?Life cycleIs LCCA difference less than 15%?EngineeringIs there a preferred alternative?
33 WSDOT LCCA Sets standard procedure and assumptions Only consider differential factorsUses NPVGives values for user costSets analysis periods50 years for Interstate or Principal Arterial20 years for Minor Arterial or Major CollectorFormal process for determining pavement type
34 Primary ReferencesWalls, J. and Smith, M.R. (1998). Life-Cycle Cost Analysis in Pavement Design. Report No. FHWA-SA FHWA, Washington, D.C. team/DP115TechBulletin.pdfWSDOT. (2005). Pavement Type Selection Protocol.