thumbnail

Methods for assessing channel conditions related to scour-critical conditions at bridges in Tennessee

Water-Resources Investigations Report 94-4229

By:
, , , and

Links

Abstract

The ability to assess quickly the potential for scour at a bridge site, to evaluate those bridges with the greatest potential for significant amounts of scour, and to then identify scour-critical structures is important for public protection and bridge maintenance planning. A bridge-scour assessment information form was developed for collecting data describing the bridge site; the hydraulic geomorphic, and vegetation characteristics of the channel. Information from site assessments of 3,964 bridges in Tennessee was used to develop indexes of potential scour characteristics over broad geographic areas, such as counties, regions, or drainage basins. Channel instability charac- teristics differ from region to region. In west Tennessee counties, channel instability has progressed from valley bottoms into the uplands through headward degradation. In middle and east counties of Tennessee, channel widening is a dominant process, but widespread degradation has been prevented by stream beds being lines with erosion-resistant bedrock, boulder, cobble, and gravel, and by the absence of channelization. Neither quantifiable headcutting nor degradation in bedrock channels was noted at any site in the State. However, potential for lateral scour is prevalent in Middle and East Tennessee.

Additional Publication Details

Publication type:
Report
Publication Subtype:
USGS Numbered Series
Title:
Methods for assessing channel conditions related to scour-critical conditions at bridges in Tennessee
Series title:
Water-Resources Investigations Report
Series number:
94-4229
Edition:
-
Year Published:
1995
Language:
ENGLISH
Publisher:
U.S. Geological Survey ; Earth Science Information Center, Open-File Reports Section [distributor],
Description:
iv, 54 p. :ill., maps ;28 cm.