BRIDGE RESCUE: Staggering load

Bridge industry strains under weight of growing needs

Bridges Article January 15, 2014
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Not enough money to do everything that needs to be done: That is the bottom line in describing the status of the bridge industry in the U.S.


One in nine of the nation’s total bridges is rated structurally deficient—meaning that some component of the bridge needs repair or replacement—according to the American Society of Civil Engineers (ASCE), while the average age of the nation’s 607,380 bridges is currently 42 years.


The state departments of transportation are slowly whittling down the list of structurally deficient bridges in the country, as they concentrate resources on improving that measure of success, but an onlooker has to wonder whether the states are delaying maintenance work on the good bridges while they focus on the bad bridges.


“The good bridges are slowly deteriorating in many states over time, while the bad bridges are slowly getting better,” David Severns, P.E., assistant chief structures engineer for the Nevada DOT Bridge Inventory/Inspection division, told ROADS & BRIDGES.


Some states faced with limited funds have taken action to increase their revenue available for bridge work. Pennsylvania recently passed a bill to increase revenue. Wyoming has hiked its gas tax by 10 cents a gallon. Virginia has passed a sales tax, which will grow with the price of gasoline, unlike the ordinary gas tax. Maryland, Vermont, Massachusetts and Maine also have taken action to increase transportation funding, Andy Herrmann, principal, Hardesty & Hanover, and 2012 president of ASCE, told ROADS & BRIDGES.
ASCE issued its “Report Card for America’s Infrastructure” in March 2013 and gave the country’s bridges a grade of C+, better than the C they got last time but still not a high grade.


The reason the grade improved was because the states are focusing more attention on improving structurally deficient bridges, and the numbers are starting to move, “not at a fast rate but at a very slow rate,” Herrmann said, “so we’re showing some signs of progress, and that’s more due to local, state and city government starting to put more investment into their bridges rather than the federal government.”


The total investment in bridges has been increasing since at least 2003, according to analysis from the American Road & Transportation Builders Association (ARTBA).


“One thing that we look at very carefully here is the amount of investment in bridge work, and we have absolutely seen an increase in the real value of that market over the last 15 years,” Alison Premo Black, vice president/policy and chief economist for ARTBA, told ROADS & BRIDGES. “It’s more than doubled, and we have seen a fundamental shift where a lot of states and local governments are putting significant resources into addressing their bridge-condition issues. We’ve seen a steady increase in investment from state and local governments. Even over the last five years since the recession hit, we’ve seen record levels of investment in the market.”


Tremendous need
Yet there are still a significant number of bridges that are structurally deficient. As some are repaired and taken off the list, others deteriorate and are added to the list.


“I think it just goes to show the tremendous needs that even with some of the levels of investment, you still have a number of bridges that are still listed as structurally deficient or functionally obsolete,” said Black. “So I think we’re making progress in areas, but there’s still some tremendous needs out there.”


Black cited indications that the increase in bridge work may be coming at the expense of other work.


“We have definitely seen at the national level since 2008, since the recession hit, the real value of pavement work on highways has steadily declined significantly,” she said. “The share of bridge work has been growing significantly, and pavement work has been declining, both in market share and the real value.”


Along with the physical condition of the bridges, ASCE’s grade also reflects the capacity of the infrastructure to meet current and future demands, funding from all sources, whether the funding available is enough to meet the demand, operations and maintenance practices, and innovation.


“The Federal Highway Administration (FHWA) estimates that to eliminate the nation’s bridge backlog by 2028, we would need to invest $20.5 billion annually,” according to ASCE’s report card, “while only $12.8 billion is being spent currently.”


In “Failure to Act,” another ASCE report, the engineers looked at the cost to society of continuing to underinvest in bridge infrastructure. Carrying on at the current level of underinvestment through 2020, the cost of moving goods and services would increase by $430 billion.


“We’d lose ground in the global economy,” said Herrmann. “Our exports would drop by $28 billion, and our gross domestic product would underperform by $900 billion.
“Then we said, ‘What would we have to spend to prevent this?’ For transportation it was an investment of an additional $94 billion per year. With that you can protect 1.1 million jobs. You can save 2 billion hours in travel time. You can save each family over $1,000 per year. And you can add $2,600 in gross domestic product for every person in the United States.


“If you look at what you’re investing versus what you’re getting back, it’s actually paying more than your investment.”


Informed decisions
Helping states decide where their money will do their bridges the most good are asset-management systems, also a requirement of the latest transportation authorization bill, Moving Ahead for Progress in the 21st Century Act (MAP-21). Each state will be required to formulate a bridge asset-management plan and show progress toward its goals.
Asset management is not a new concept, and some states are already applying it to their bridges on a sophisticated level, according to Tom Everett, team leader, Bridge Safety, Preservation and Management Team, FHWA.


“It’s using tools to help you make good decisions,” Everett told ROADS & BRIDGES, “and in some cases, those decisions might point you more toward preserving your existing bridges rather than focusing on replacing the ones that are so bad that they’re already structurally deficient.”


The FHWA is currently going through a rulemaking process to determine exactly what the federal requirements should be regarding state bridge asset-management systems. The federal requirements will provide guidelines for a successful system but will not determine what bridge work the states do.


The FHWA also is working through a rulemaking process to determine performance measures for the state bridge programs.


“They’re giving us more flexibility in how we spend the money, but at the same time we have to demonstrate performance,” said Severns, “so that we’re showing that the money is actually having an effect, it’s actually making our bridges better.”


A measure of performance might look something like the percentage of bridge deck area on the National Highway System that is categorized as structurally deficient. In fact, in Severns’ state of Nevada, they track that percentage: “In Nevada, for example, we’ve calculated that right now we’re at 0.59%. So our bridges, population-wide, are in very, very good shape.”


A state that fails to keep its bridges in acceptable condition might face some kind of sanction.


Nevada has several other performance measures the state needs to meet. One is imposed by the state legislature. Another is written into the state’s stewardship agreement with the FHWA. So performance measures are already a familiar part of doing business.


An extremely unfamiliar event is the catastrophic collapse of a U.S. bridge, with the loss of lives, but that is what happened to the I-35W bridge over the Mississippi River in Minneapolis on Aug. 1, 2007.


Component shakeup
“The biggest things that have come out of Minneapolis are changes and protocols with regard to design of bridges,” Severns said. “We’re paying a lot more attention to those components such as the ones that failed, that led to the disaster in Minneapolis, like gusset plates. We have new protocols regarding the design of gusset plates on bridges like that. We have protocols on the analysis of existing gusset-plate components, where we ascertain their strength. We have protocols on inspection of gusset plates to make sure the bridge inspection staff is doing a good job identifying conditions and monitoring them over time.”


“We did a lot on the topic of gusset plates after I-35W,” Everett said, “We learned a lot more about how gusset plates should be designed and load-rated.”


The FHWA also went through internal auditing of its oversight of bridge inspections: “That has led us to a much better place nationally as far as compliance with things like inspection intervals,” Everett explained. “We are taking a much closer look at state practices. There are 23 different metrics of compliance that we are now examining very closely every year. We now have a much better handle on the state of compliance than we ever did before.”


Another factor complicating the bridge industry is that MAP-21 expires in a mere nine months (Sept. 30, 2014) to be replaced by . . . no one knows what.


There are still positive signs in the bridge market. There are a bunch of major projects in progress.


“There’s enough in contract awards that have happened over the last 12 months that I think you’re going to continue to see a healthy market of ongoing work over the next few years,” Black said, “but I think you will start to see a slowdown or a leveling off in bridge investment several years from now if the Highway Trust Fund situation is not addressed.”
Perhaps ongoing bridge projects will help sustain the industry through uncertain times. R&B
 

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