Table 4. Percentage of channel blocked by drift at selected
scour-potential-study bridges.
Percentage of
channel blocked
Number of
selected bridges, by State
Greater
than
Less than or equal to
Indiana
Maryland
Massachusetts
South Carolina
Tennessee
75
100
3
1
0
35
6
50
75
2
1
0
28
18
25
50
28
7
1
100
74
5
25
104
51
16
409
282
0
5
133
62
37
481
422
0
2,124
757
702
2,445
2,779
Total number of bridges
2,394
879
756
3,498
3,581
Percentage of channel blocked
Percentage of selected
bridges, by State
Greater
than
Less
than or equal to
Indiana
Maryland
Massachusetts
South
Carolina
Tennessee
75
100
0.1
0.1
0.0
1.0
0.2
50
75
0.1
0.1
0.0
0.8
0.5
25
50
1.2
0.8
0.1
2.9
2.1
5
25
4.3
5.8
2.1
11.7
7.9
0
5
5.6
7.1
4.9
13.8
11.8
0
88.7
86.1
92.9
69.8
77.5
Total of percentages of
bridges
100.0
100.0
100.0
100.0
100.0
U.S. Department of the Interior, U.S. Geological Survey
Maintainer:webmaster@tn.water.usgs.gov
Last update:
Tuesday, 08-Jan-2013 14:46:25 EST
URL: http://tn.water.usgs.gov
/publications/FHWA-RD-97-028/table_4.htm
USGS Privacy Policy || Disclaimer