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Τρίτη, 10 Δεκεμβρίου 2019

Εκθεση του Οργανισμού Transportation for America για την κατάσταση των γεφυρών στις ΗΠΑ: 66.405 γέφυρες, το 1/9 των υπαρχουσών, εμφανίζουν προβλήματα δομικής ακεραιότητας, ωστόσο τις διαβαίνουν 260 εκατομμύρια οχήματα ημερησίως!

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The Fix We’re In For: The State of Our Nation’s Bridges 2013 TRANSPORTATION FOR AMERICA Creative Commons photo of the I-5 Skagit River bridge by Flickr user WSDOT http://www.flickr.com/photos/wsdot One in nine bridges remains structurally deficient Every day, millions of people from all walks of life in cities and towns large and small travel over one of our country’s 66,405 structurally deficient bridges — more than one in nine (11 percent) of all bridges. Structurally deficient bridges are those that require significant maintenance, rehabilitation or replacement. We take 260 million trips over deficient bridges each day. In our 100 largest metropolitan areas alone, there are more structurally deficient bridges than there are McDonald’s restaurants in the entire country. Laid endNot surprisingly, age takes a toll. Structurally deficientto end, all the country’s deficient bridges would spanbridges are 65 years old on average — more than 22from Washington, DC to Denver, Colorado — more thanyears older than all bridges. Herein lies a glimpse of1,500 miles. (Or farther than from Canada to Mexico.)the future fix we’re in for: In just 10 years, one in four bridges (170,000) will be over 65, an age at which it’sWhile most bridges are designed to last 50 years beforefar more likely that a bridge will be deficient.major overhaul or replacement, the average age of an American bridge is well past middle age at 43 years.About this data This report is derived from the National Bridge Inventory, a compliation of state-collected data, which is reported to and then published by the Federal Highway Administration (FHWA). This data was released in early 2013 and was reported to the FHWA at different times by states in 2012. It’s perhaps most helpful to think of the NBI dataset as a summary of bridge conditions during a period of time, not a single specific moment. States report their data to FHWA at different points during 2012, and repairs may have been made in the many months between their reporting date and the release of the FHWA dataset. States have the most up-to-date bridge data, but this is the sole complete national source of bridge data. 2 T4 AMERICAThe Fix We’re In For: The State of our Nation’s Bridges 2013THE STATE OF OUR NATION’S BRIDGESBridges may be rated deficient for a range of reasons and not all of them pose an immediate threat to publicWhat does “structurally deficient” mean?safety. However, allowing bridges to remain in serious need of repair can lead to the sudden closure of a critical transportation link or, far worse, a collapse thatHighway bridges have three primary compo-results in lives lost and a major economic impact to thenents: 1) the deck, which is the top surface ofaffected region.the bridge that cars, trucks and people cross; Considering declining gas tax revenues for2) the superstructure, which supports thetransportation and other budget woes, securing thedeck; and 2) the substructure, which uses themoney to repair or replace thousands of bridges, whileground to support the superstructure. Each offixing the other parts of our aging highway and transitthese bridge features is given a rating between 0networks, is a critical national issue. The maintenanceand 9 when inspected, with 9 signifying the bestbacklog will only grow as bridges age and costs rise. The Federal Highway Administration estimates thatcondition. Federal guidelines classify bridgesrepairing our deficient bridges would cost a staggeringas “structurally deficient” if one of the three key$76 billion. This figure will likely increase as many of ourcomponents is rated at 4 or less (poor or worse),most heavily traveled bridges – including those builtmeaning engineers have identified a major defectmore than 40 years ago as part of the Interstate systemin its support structure or its deck. (There are– near the end of their expected lifespan.a handful of other criteria that can result in aMeanwhile, Congress last year introduced a wild carddeficient grade, but for the majority of deficientinto the mix by passing legislation that eliminated abridges, one of these three primary componentsdedicated fund for bridge repair in the renewal ofrates a 4 or below.) Federal law requires statesthe federal transportation program, known as MAP-21.to inspect all bridges 20 feet or longer at leastInstead, states are directed to set standards that theyevery two years, though states typically inspectexpect to meet for repair, but with limited enforcementstructurally deficient bridges far more often.in case of failure. The upshot is that bridge repair now 3 T4 AMERICAThe Fix We’re In For: The State of our Nation’s Bridges 2013THE STATE OF OUR NATION’S BRIDGESmust compete with other transportation needs. At the same time, the new law reduced access to funds for the nearly 90 percent of structurally deficient bridges that are not part of the so-called National Highway System (the interstates plus larger state highways).Slow – and slowing – progressYear# of bridges (last year of cycle)# deficient (last year of cycle)1992572,196118,698bring the share of deficient bridges down slightly, from93-96581,862101,5183.3%11.5 percent to 11 percent. This is a continuation of97-00587,45886,6922.7%progress made over the last 20 years in reducing the01-04593,88577,7581.7%05-08601,41171,4691.2%09-12604,99566,4050.9%The good news is that some states have worked hard to address the problem and have reduced the backlog of deficient bridges. Since our 2011 report, investments from the American Recovery and Reinvestment Act and ongoing transportation programs have helpedtotal number of deficient bridges, but the bad news is that that progress has slowed markedly. In the fouryear period from 1992-1996 transportation agenciesPercent improvement per 4-year periodreduced the number of deficient bridges by 17,000. But in the period from 2008-2012, the number dropped by only about 5,000 – a rate three times slower than in theHowever, not all states have made progress since ourearly 1990s.last report. 15 states have more deficient bridges today than they did in 2011. (See map on following page.)Among the 10 states with the largest share of deficient bridges in our 2011 report, seven managed to reduceArizona, Delaware and Hawaii were the largesttheir total number of deficient bridges (though their rankgainers, growing their total of deficient bridges bymay have stayed the same). Pennsylvania remains5 percent or more over 2011. Roughly one in fivenumber one with one in four bridges rated structurallybridges is structurally deficient in Oklahoma, Iowa,deficient, but made one of the largest gains against itsRhode Island, South Dakota and Nebraska. Andmaintenance backlog, reducing the number of deficientOklahoma also led the way in real numbers, increasingbridges by more than 8 percent. In terms of numberstheir total of deficient bridges by about 77 in two years,of structurally deficient bridges, Missouri reduced itsahead of other top worsening states New York (61),total by 640 in the two years since our last report, whileLouisiana (51), and Minnesota (40).Pennsylvania reduced its number by 500 and Ohio dropped by 327.4 T4 AMERICAThe Fix We’re In For: The State of our Nation’s Bridges 2013THE STATE OF OUR NATION’S BRIDGESMay 2013: I-5 collapse and “fracture-critical” bridges The Interstate 5 bridge that collapsed into the Skagit River in May 2013 was not structurally deficient but it was denoted to be “fracture-critical” in its design, lacking redundant supporting elements. This designation means that a failure of one of those components can lead to collapse. Scary as it sounds, fracture critical bridges are deemed perfectly safe as long as they remain structurally sound, as the I-5 bridge apparently was. There are nearly 20,000 other bridges that have “fracture critical” designs. The Skagit River bridge, though in good repair, was a strong candidate for replacement, nevertheless, because it was built before the Interstate highway system and later incorporated into it. It was not designed to carry the large loads of today’s interstates. Indeed, it collapsed when an overly tall tractor-trailer - carrying a legal load for the Interstates - clipped the overhead support beams. Ideally, a robust federal program would ensure systematic replacement of such heavily traveled, outdated bridges over time.An uncertain future for bridge repair and safetyThe change was also made with little transition toFor the last 30-plus years, the federal transportationThe new performance measures system will takeprogram maintained a dedicated fund for repairingseveral years to set up – but the dedicated bridge fundstructurally deficient bridges. The program beganwas eliminated starting in 2013 before the new systemin 1978, when Congress dedicated funding to helpis in place. These changes come as progress on bridgeimprove the nation’s bridges, and was given newrepairs has slowed in the face of a rapidly aging system,emphasis in the 1991 law known as ISTEA. For the 20and as states and localities grapple with competingyears after 1991 more than 50,000 deficient bridgespriorities after years of depressed revenues.allow for Congress and the public to see how this new system will work.were repaired. But the lion’s share came in the first 10 years, and since then progress had slowed significantly,Congress also reduced access to funding for the repairas noted above. The exact reasons why are a subjectof most locally owned bridges, which are twice as likelyfor further study. It’s possible that states fixed theto be structurally deficient as those on the state andbridges with the lowest cost first, or that they shifted their priorities to other areas, perhaps due to the increasingly constrained funding of recent years. Congress took a new approach – and something of a gamble – with the 2012 renewal of the transportation of program, MAP-21. For one, the new law eliminated the dedicated bridge fund, allowing states to program money as they see fit. In principle, states will be required to meet maintenance standards set under a new system of performance measures. However, that system has yet to be established, and the mechanisms for enforcement are limited. 5 T4 AMERICAThe Fix We’re In For: The State of our Nation’s Bridges 2013THE STATE OF OUR NATION’S BRIDGESfederal sytems, as well as state-owned bridges that areIncrease investment: MAP-21 is a short-term billnot designated as part of the National Highway Systemthat relies on about $19 billion in transfers of general(NHS). Although these bridges account for nearly 90revenues from the Treasury Department to keep thepercent of all deficient bridges, MAP-21 now focusesHighway Trust Fund solvent through September 30,all funding from the former bridge repair program on2014, when the bill expires. In FY2015 alone, the Trustthe ten percent of deficient bridges on the NHS, whichFund will need an additional $14 billion in transfers toincludes the interstates and most larger state highways.remain solvent. Current spending levels are precarious and inadequate. This situation cannot continue. In orderCertainly, bridges on the NHS roadways are critical,to bring our rapidly aging infrastructure up to a stateand carry vast numbers of people and goods, butof good repair, Congress should raise new dedicatedthese other bridges also provide essential links, andrevenues for surface transportation programs, includingthose who use them also deserve to be safe. Givenbridge repair.the budget woes of so many local governments, there is little prospect of reducing the repair backlog absentMake all 180,000-plus federal-aid bridges eligiblefederal assistance. As it stands now, however, thesefor National Highway Performance Progam funds:bridges are forced to compete with all other localUnder MAP-21, all of the money previsouly set asidetransportation projects for funding from a single pot offor bridge repair was rolled into the new Nationaltransportation dollars that did not grow to meet theseHighway Performance Program, which representsnew responsibilities.60 percent of all federal highway funding. National Highway Performance Program (NHPP) funds mayRecommendationsonly be spent on a limited subset of highways knownThe current surface transportation authorization willpercent of all highway bridges, and only ten percent ofas the National Highway System, representing only 23 all deficient bridges. That is in contrast to the formerexpire on September 30, 2014. Transportation forbridge program, for which 600,000-plus bridges wereAmerica recommends that the next authorization takeeligible for federal support. Given that nearly nine inthe following steps to reduce the maintenance backlog,ten deteriorating bridges are located off of the Nationalbring our bridges to a state of good repair and keepHighway System, the next federal authorization shouldusers safe.allow the repair of these 180,000 “federal-aid” bridges 6 T4 AMERICAThe Fix We’re In For: The State of our Nation’s Bridges 2013STATE DATA & RANKINGSto be funded by the National Highway Performance Program, as they were eligible for repair dollars under the previous Highway Bridge Program. Prioritize Repair The next federal transportation bill should make the repair of highways and bridges a national priority. Specifically, Congress should require states to set aside a share of their NHPP funds for bridge repair unless the state’s bridges are certified as being in a state of good repair.National Rankings and State Data Note: full state and county level summary statistics are available online at t4america.org/resources/bridges Deficient Bridges 2011 (FHWA)Change in deficient bridges over 2011Percent change in deficient bridge totalAverage daily traffic on deficient bridgesStateRank2013 % deficientTotal bridgesDeficient bridges 2013Pennsylvania124.522,6675,5436,043-500-8.3% better18,994,224Oklahoma222.623,7785,3825,305+771.5% worse7,236,161Iowa321.224,4655,1915,440-249-4.6% better1,728,828Rhode Island420.7754156163-7-4.3% better2,598,405South Dakota520.65,8691,2081,198+100.8% worse354,303Nebraska61815,3912,7782,820-42-1.5% better724,206North Dakota716.84,445746727+192.6% worse95,368New Hampshire*814.92,429362383-21-5.5% better1,796,425Maine914.82,408356389-33-8.5% better924,423Missouri1014.524,0723,5024,142-640-15.5% better5,156,617Mississippi1114.217,0532,4142,713-299-11.0% better1,401,786Wyoming1213.73,101426407+194.7% worse871,031Louisiana1313.613,2581,7981,747+512.9% worse4,588,616West Virginia1413.47,0899521,025-73-7.1% better2,325,812Hawaii1513.31,146152144+85.6% worse1,862,562D.C.1612.824231310no change915,533New York1712.517,4202,1702,109+612.9% worse17,374,731Michigan1812.311,0001,3541,539-185-12.0% better7,542,647South Carolina1912.29,2521,1271,232-105-8.5% better3,397,465California201224,7972,9783,256-278-8.5% better67,603,788North Carolina211218,2802,1952,362-167-7.1% better7,850,103Alaska2210.91,173128146-18-12.3% better178,675Indiana2310.818,7532,0301,995+351.8% worse7,199,952Vermont2410.62,726288344-56-16.3% better426,822Kansas2510.525,2062,6572,833-176-6.2% better812,743New Jersey269.96,557651682-31-4.5% better11,285,681Connecticut279.74,196406390+164.1% worse5,274,7017 T4 AMERICAThe Fix We’re In For: The State of our Nation’s Bridges 2013STATE DATA & RANKINGSMassachusetts289.65,132495565-70-12.4% better9,151,876Idaho299.44,213397384+133.4% worse565,589Ohio309.127,0022,4622,789-327-11.7% better9,223,025Virginia319.113,7691,2511,272-21-1.7% better7,393,364Minnesota329.113,1091,1911,151+403.5% worse2,342,495Alabama33916,0711,4481,608-160-10.0% better2,368,186Kentucky348.914,0281,2471,319-72-5.5% better4,416,436Illinois358.726,5142,3112,289+221.0% worse8,035,705Wisconsin368.214,0941,1511,153-2-0.2% better2,923,488New Mexico377.83,924307332-25-7.5% better719,135Montana387.85,120399407-8-2.0% better503,175Arkansas397.112,648899949-50-5.3% better1,526,375Maryland406.95,286364367-3-0.8% better5,344,961Colorado416.68,578566584-18-3.1% better4,711,767Delaware426.18625350+36.0% worse323,720Georgia43614,730878953-75-7.9% better2,319,651Tennessee*445.920,2681,1951,236-41-3.3% better4,885,931Oregon455.77,631433463-30-6.5% better1,484,388Washington464.67,806362400-38-9.5% better2,925,184Utah474.32,941126133-7-5.3% better880,780Arizona483.27,830247233+146.0% worse1,837,167Texas492.652,1281,3371,662-325-19.6% better3,068,190Nevada502.21,7974039+12.6% worse146,557Florida512.211,987265300-35-11.7% better1,583,17811%604,99566.405National Totals* 2012 FHWA summary statistics are used for New Hampshire and Tennessee’s deficient bridge totals due to significant discrepancies between FHWA summary statistics and the data in the NBI.This report was written by Stephen Lee Davis and David Goldberg, based on an analysis of the National Bridge Inventory by Kevin DeGood, with additional contributions from Nick Donohue and James Corless of Transportation for America. Layout and design by Stephen Lee Davis, with graphics by Anagram. Released June 19, 2013. More information about the data and report can be found at t4america.org/resources/bridgesAbout Transportation for America — Transportation for America (T4 America) is the largest, most diverse coalition working on transportation reform today. We believe it is time for a bold new vision — transportation that guarantees our freedom to move however we choose and leads to a stronger economy, greater energy security, cleaner environment and healthier America for all of us. We’re calling for more responsible investment of our federal tax dollars to create a safer, cleaner, smarter transportation system that works for everyone. 1707 L Street NW, Suite 250 Washington, D.C. 20036 202.955.5543 info@t4america.org 8
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