Click for next page ( 23

The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement

Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 22
23 CHAPTER SIX CONCLUSIONS The literature review; a survey of the largest transit agencies, Often, there is limited consideration given as to how the with an 82% response rate; and case studies yielded some key inventory and condition data might be integrated to sup- findings regarding the state of the practice in transit asset man- port short-term and strategic planning and investment agement and the limitations in current methods. The results of policy. As a result, human interaction is needed to adapt the synthesis also suggested additional research to improve or process the data for these activities. transit asset management practices. Most large transit agencies determine asset condition through a combination of age and inspection results. Good transit asset management can provide critical support Many agencies assess the condition of selected asset in two key areas: categories such as bridges based on inspections while relying on age for other asset categories. Most transit 1. Establishing the level of need for infrastructure agencies are not using decay curves for assessing cur- investments. A comprehensive analysis of infrastruc- rent State of Good Repair (SGR) or projecting future ture needs can produce an estimate of the funding investment needs. Decay curves depict the relationship needed to address (1) ongoing asset replacement and among asset condition, useful life, and maintenance rehabilitation needs, and (2) past unfunded infrastruc- practices and were initially developed by the Chicago ture needs (often termed backlog needs). This funding Transit Authority. They are key elements of FTA's estimate and supporting documentation can provide a Transit Economic Requirements Model (TERM). compelling argument and support for increased funding. The assessment of SGR needs has benefited many transit 2. Programming of cost-effective investments. A sys- agencies. Most large transit agencies use inventory and tematic approach that is based on good quality data and condition assessment data to estimate both current and clear organizational objectives can help prioritize the future SGR backlogs and investment needs. The agen- programming of investment projects when available cies stated that their asset condition systems were used to funding is constrained and not sufficient to support the change capital funding priorities to improve their SGR. implementation of all needed projects. The use of this The two case studies demonstrated that focused attention approach will help maximize the effectiveness of local, to transit asset management can improve the funding of state, and federal funding investments. SGR projects. The large transit agencies do not use asset condition data The synthesis revealed the following key findings about the to set investment priorities for capital programming. state of the practice at the largest transit agencies: Most large transit agencies use the transit asset condition data as another qualitative factor to be considered in Most large agencies have asset tracking databases that the determination of investment priorities and devel- are frequently updated and include all assets. The opment of capital programs. This was even true for the primary data sources vary but include financial Massachusetts Bay Transportation Authority (MBTA) records (fixed asset ledgers), asset inspections, main- application, which has the ability to prioritize the funding tenance management systems, or some combination of of specific asset renewal or replacement projects in con- these sources. There are variations in how the data are strained funding environments. stored including the use of off-the-shelf, financial information or asset management databases, and spe- The current methods used by the large transit agencies sur- cial databases developed internally or by outside con- veyed are at an elementary level. The key issues with the meth- sultants. Most agencies use designated in-house staff to ods are: support and update the databases for most responding agencies. The appropriate measurement of SGR using age and/or Many transit agencies maintain separate equipment ros- condition. ters that are independent from the mainstream planning, The limited estimation of benefits or consequences of programming, and budgeting processes. This is done for alternative investments. internal maintenance management and to meet federal The absence of scenario testing for different funding requirements for adequate control of grant-funded assets. levels.

OCR for page 22
24 The synthesis revealed that there has been significant dis- Unfortunately, these impacts have been difficult to estimate cussion of the appropriate measurement of SGR using age and are not explicitly considered by most large transit agen- and/or condition among large transit agencies. In concept, cies. Most agencies rely on the expert judgments of transit most managers at large transit agencies believe that condi- managers and engineers and assume that these experts weigh tion is the best measure of SGR because it recognizes that these factors as they define the times when assets should be the need to replace an asset in practice is related not only to replaced. age, but to other factors such as intensity of use (e.g., miles), level of preventive maintenance, and climate. However, The Illinois Department of Transportation effort is an exam- condition measurement often incorporates on-site inspec- ple of how the impact on operating costs could be determined. tions and evaluations by expert engineers--a costly ongoing The Illinois model estimated the life-cycle costs of different expense for many transit agencies faced with tight funding. types of buses, including operating, maintenance, and capi- tal costs. The resulting total cost curves were used to deter- Condition measurements are most helpful for making mine the service lives that minimized total costs. The data detailed, short-term investment decisions that involve invest- from these curves could also be used to estimate the added ment actions for specific assets in an asset class with common cost impacts of deferring bus replacements beyond these ser- characteristics (e.g., how many 14-year old buses should be vice lives. programmed this year in view of other investment needs?). Finally, the ability to perform scenario testing is limited at Age is viewed as a simple and less desirable (compared most transit agencies. Most large transit agencies use inven- with condition) measure of SGR because it does not recognize tory and condition assessment data to estimate the funding the other factors that contribute to the physical declines of dif- needed to eliminate current SGR backlogs. They also esti- ferent assets. The use of age implies it is reasonable to apply mate future funding needed to maintain SGR. Both of these one service life for an asset type (e.g., conventional buses) approaches are useful for arguing for additional funding to in all situations. Age data have the advantages over condi- reach "ideal" operating environments. tion data of being easier to collect and maintain and to explain to decision makers. However, decision makers and the general public are skep- tical of these "ideal-based" funding estimates. Often, it is Age data may be a reasonable way to make appeals for believed that it is not possible to provide this ideal level of more SGR funding because of these advantages. These advan- funding. Instead, there is an interest in determining the impacts tages may also apply to long-term planning activities that, by of lower levels of funding. Often, the discussion begins with nature, are willing to use more simple models of condition. determining the level of funding needed to halt the decline in the SGR for a transit agency. It then advances to questions Fundamentally, the tradeoffs of using age data versus about the benefits of increasing funding beyond this "SGR condition data involve the degree of variation (variance) in steady-state" funding. replacement ages based on analysis of condition data. For example, if the analysis of condition data suggests that most A methodology is needed to prioritize the funding of spe- buses should be replaced between 12 and 14 years, then using cific asset renewal or replacement projects when these scenar- an age-based service life of 13 years is reasonable and saves ios involve funding that is less than what is needed to bring all the added costs of condition inspections. However, if this vari- assets to SGR and maintain them at SGR. Only the application ance is wider, for example 12 to 18 years, then using condition at the MBTA in Boston has this ability to test different fund- data is preferable and warrants the added costs of condition ing environments because it has a programming logic that can inspections. prioritize the funding of specific asset renewal or replacement projects in constrained funding environments. Although this Unfortunately, the synthesis did not identify significant work is widely known, managers from the large transit agen- efforts to address the age versus condition issue. The contin- cies expressed interest in learning more about the develop- ued development of decay curves for FTA's TERM model and ment, use, benefits, and limitations of this prioritizing tool. other agency applications may add more insight to this issue. Additional research on the effective design and use of asset The estimation of the benefits (or consequences) of invest- databases is suggested. The research might focus on the fol- ment decisions is seldom performed in current practice. Gen- lowing issues: erally, the benefits are estimated as the degree to which the SGR has been achieved (e.g., 70% of assets are in SGR, the The structure and level of detail in effective databases. average rating is 3.2). However, these SGR measures are Research to define the elements of a good asset condition really surrogates for the potential impacts of SGR investments inventory database addressing issues such as database that have real meaning to decision makers and the general structure, function, data requirements, assets covered, public--impacts such as reduced operating costs, improved frequency and method of updates, analytical capabilities, reliability, and increased safety. and helpful output reports. The potential of sharing good

OCR for page 22
25 asset inventory database software or specific database The estimation of the benefits (or consequences) of analysis modules might also be investigated. investment decisions. Research to examine analytical The effective use of age and condition-based assessments methods for estimating the potential impacts of SGR of SGR for different asset types. Research to examine the investments that have real meaning to decision makers degree of variation (variance) in replacement ages based and the general public--impacts such as reduced operat- on analysis of condition data. For some asset types, it ing costs, improved reliability, and increased safety. may be determined that age is an appropriate measure. The use of prioritization decision tools for examining the For other asset types, it may be determined that the impacts of different SGR funding levels. Research to added cost of condition measurements and inspections examine the effective design and use of such tools and is warranted. their benefits and limitations.