This month, the Federal Highway Administration (FHWA) is planning to award a 20-year contract to a team of technical experts for development of the next generation of bridge management processes.
The main objectives of this program will be to reduce variability and subjectivity in condition assessment, develop bridge deterioration models from objective in-service performance measurements, formulate the next generation of design standards for newly constructed bridges and maximize the life span of bridges while minimizing their life-cycle cost. In practice, the Long Term Bridge Performance (LTBP) program will gather voluminous data on bridges and develop new knowledge that will allow further optimization of bridge design standards, bridge maintenance methods and repair/replacement decisions. The question we will examine is whether this program is a boon or boondoggle for taxpayers.
Less eyesight, more foresight
Forty years ago, the Silver Bridge collapse in West Virginia resulted in the development of the National Bridge Inspection Standards (NBIS) program. The NBIS program was the foundation for an integrated management approach that encompassed the following: periodic, visual bridge condition assessment inspections; the data structure for more formal, computerized bridge management systems (e.g., Pontis); and a basis for the federal government to provide matching funds for repair or replacement of bridges. For nearly 30 years, this integrated program worked reasonably well, with only a few tragic bridge failures during that period. But the real driver for this program’s success was robust transportation funding—states generally received all the money they needed.
However, looking to the future, necessary transportation funding will be usurped by nondiscretionary federal budget items (e.g., interest payments on debt, Medicare, Social Security and a host of smaller programs that Congress cannot or will not reduce or eliminate). Demonstrably robust transportation funding is not on anyone’s radar screen, despite the recent rhetoric from Capitol Hill. Unfortunately, every owner’s bridge management program will have to adjust to this new reality—and quickly.
As we entered the 21st century, several important yet seemingly unrelated developments sparked a rethinking of how transportation owners should manage their bridge inventory. The first development, intuitively obvious, was continued bridge aging. Many U.S. bridges have passed their intended design life with little to no chance of being replaced for decades to come. Yet, no matter how effective the initial design or robust the factors of safety, our bridges continue to decay and there’s simply no way to stop that process. Contributing to declining bridge conditions are deferred maintenance, continued use of deicing chemicals (salt compounds), corrosion and scour. In an unintended way, the inevitable process of decay has been accelerated by a strong economy, resulting in increased traffic demands, especially from heavy trucks, acting as rolling warehouses for our “just-in-time” economy.
The second development was the endless debating and inevitable delay in passing the SAFETEA-LU bill, which spotlighted the long-term funding challenge. There just was not enough funding available to repair or replace bridges classified as deficient or obsolete (structural and functional) and to build desperately needed increased capacity, especially around large cities. Something had to give and maintenance expenditures became the balancing mechanism, further exacerbating the process of decay.
Third, a 2001 FHWA study on bridge inspection efficacy highlighted the shortcomings of the NBIS visual inspection protocol. While not surprising to experts, this study clearly demonstrated that overreliance on subjective, variable visual inspection information to drive funding decisions could cause unintended consequences, such as premature replacement or unsafe conditions—both poor outcomes. In addition, since federal bridge funding eligibility was biased toward lower condition assessments, the fastest path to more money was ever more conservative condition assessments. The phrase, “When in doubt, rate lower,” made perfect sense for decades when funding was robust.
Fourth, the process of asset management (AM) took flight. This management paradigm, a blend of technical and financial balance sheet optimization for large, asset-heavy organizations, was supported by the FHWA as the next-generation management process for state DOTs. Much good thinking went into the development of AM processes, and a few states have reported good results—Michigan being the much-admired poster child. In conjunction with AM, the Governmental Accounting Standards Board (GASB) adopted Statement No. 34, which required forward-looking financial statements (long-term capital plans) from public entities to enable more objective decisions on bond ratings. Suddenly, down-rating of assets caused more unintended consequences, such as the accounting requirement to address (and fund) upcoming major repair or replacement projects. GASB No. 34 rightly assumes impaired assets cannot be ignored by the owner.
The fifth and final development was the introduction of more precise, objective condition assessment and nondestructive testing/evaluation (NDT/E) technologies, such as structural health monitoring. While never intended to replace visual inspection, these technologies were developed as a means to reduce subjectivity, safely extend asset life (minimizing life-cycle costs) and improve long-term bridge management. The LTBP program will use these technologies, in addition to in-depth visual inspections, to amass a database for intense study and development of deterioration models.
Several years ago, FHWA staff saw the preceding developments as pieces of a puzzle that could be uniquely assembled to bring a fresh perspective and management process upgrade to owners of bridges across the country. This was strategic thinking at its best, combining seemingly disparate developments into a more powerful paradigm that could provide benefits to owners, taxpayers and public transportation users. No boondoggle here.
Will rises after collapse
The tragic Aug. 1 I-35W bridge collapse sparked a hearing of the U.S. House Transportation and Infrastructure (T&I) Committee on Sept. 5 to formulate a response to this tragedy. While many in the transportation industry have for years called for action to address our bridge deficiencies, it took this tragedy to focus political will. Witnesses from the U.S. DOT were steadfast in their recommendations for improving the existing bridge condition assessment program and overall bridge management as a by-product. The following paraphrases were used by U.S. DOT witnesses and several House members:
- Improvements in standards for condition assessment and evaluation should be “data driven”;
- Improvements in bridge management should be in the context of “asset management” programs; and
- Improvements in prioritization of funding for repairs or replacements should be “risk-based” and subject to “economic analysis.”
It is no stretch to see how the U.S. DOT tied the strategy developed for the LTBP program to recent House testimony. It makes sense to use these phrases, since the FHWA has long been a proponent for better AM programs, use of better technology for condition assessment (as a supplement for visual inspection) and use of in-depth economic/financial analysis to ensure the taxpayers are getting the best return for their investments in transportation.
Chance of improvement
At the start of the 20th century, weather forecasting was in its infancy. Well before the advent of weather satellites, weathermen were noting ambient temperatures and barometric pressures while visually inspecting cloud formations, trying to understand how similar cloud formations and barometric pressure changes produced weather under similar conditions. There was no way to relate weather in Chicago on Wednesday with weather in New York on Friday—that is, until weather scientists had the ability to collect prodigious amounts of data, employ sufficient computing power and develop numerical models to produce statistical, risk-based forecasting (e.g., 70% chance of rain tomorrow).
Today, weather forecasting is a data-driven science. From satellite maps to weather balloons to weather stations across the globe, it is all about data. Data is collected by “sensing devices” (e.g., thermometers and barometers) fed electronically into supercomputers and integrated with weather prediction models to formulate a forecast for almost any location on the planet. The LTBP program is not quite that ambitious, but it is expected to produce a quantum leap in bridge management.
Winning a date with Congress
Since the FHWA has been formulating plans for a more objective, data-driven bridge management process, officials have held briefings and used other communication tools to bring this idea into the open for debate and shaping of the final program scope. Credit the smart staff at FHWA for bringing all relevant interest groups into the debate: AASHTO, state DOTs, engineering consultants, etc. While funding has only been approved through 2009, FHWA is expecting the winning team of the LTBP program to implement a reasoned, high-level and broadly supported Congressional lobbying effort to win long-term funding for the 20-year cycle. That, too, makes sense. Who else is better versed in explaining the expected return on taxpayer funds? From the LTBP program RFP, “The overall objective is to inspect, evaluate and periodically monitor a representative sample of bridges nationwide in order to collect, document, maintain and manage high-quality quantitative performance data over an extended period of time. This will require taking advantage of sensing technologies and nondestructive evaluation and testing tools in addition to typical bridge inspection approaches.”
Further, “The quantitative database developed under LTBP program will be used to solve a variety of bridge condition assessment and management problems and to develop new tools and advance knowledge of bridge design, maintenance and preservation, including the following:
- Determining how and why bridges deteriorate;
- Improved knowledge of bridge performance;
- Determining the effectiveness of various maintenance, repair and rehabilitation strategies, as well as management practices;
- Determining the effectiveness of durability strategies for new bridge construction including material selection; and
- Enabling improvements in bridge management practice using quality, quantitative data.”
One might conclude that this effort is far too ambitious for the FHWA, bridge owners and even the winning technical team (i.e., another government boondoggle). Considering the ultimate benefits to taxpayers, our long-term economic vigor, sustainability and environmental concerns, construction disruption, etc., one might ask if similar, technically oriented, government-funded programs, such as the Manhattan Project or the Interstate Highway System, were worth the effort. Who will argue that a highly focused, technically driven investment to demonstrate how bridges can meet the objectives of stronger, faster, cheaper, longer-lived, safer and greener isn’t a worthwhile pursuits? Taxpayers have trillions of dollars invested in our transportation system and deserve to have their investment optimized.
While still unfunded past 2009, the LTBP program deserves the support of all who value better transportation. This program has the promise of a substantial payback, much like President Eisenhower’s Interstate Highway System delivered. The LTBP program will be a boon for all transportation users and only a boondoggle if we do not fund and support its full implementation.
