U.S. Department of Transportation
Federal Highway Administration
1200 New Jersey Avenue, SE
Washington, DC 20590
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Conditions and Performance
Status
of the Nation's Highways, Bridges, and Transit:
2002 Conditions and Performance Report
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Exhibit 11-16:
Local Bridges
Exhibit 11-16 is a bar graph that shows the construction of local bridges. The vertical axis measures number of bridges from 0 to 25,000 in increments of 5,000 bridges. The horizontal axis has 21 bars, one for each 5-year period between 1900 and 2000. New local bridges were 7,000 before 1900, 5,000 or less for each period from 1900 to 1920, then rose sharply to 9,000 by 1930 and 12,000 by 1940. The figure dropped during WWII, then rose steadily again to 10,000 in 1950, and 15,000 to 18,000 for each period from 1956 to 1980. The peak was in 1986-90 at more than 20,000, but then it dropped to 16,000 by 2000. There are also two lines and a second vertical axis (measuring percentages from 0 to 100 in increments of 10 percent) in this chart. The first, representing cumulative percent of structure population, rises from 0 to 20 percent by 1935, 35 percent by 1955, 60 by 1975, 82 by 1990, and 100 by 2000. The other line, representing cumulative percentage of ADT, parallels the first line almost exactly, except at 1 to 5 percentage points lower.
Source: National Bridge Inventory.
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Page last modified on November 7, 2014
