Bridges that cross streams can be greatly affected by channel instabilities, such as channel widening, lateral migration and channel bed degradation. Attention to channel conditions in the vicinity of bridges is an important aspect of bridge maintenance and safety. Channel stability is also critical to goals of multi-objective river management. Given that channel stability is important for both river management and the structural stability of bridges, any river management scheme should consider the stability of bridge-stream intersections. In this paper, the characteristics of bridge-stream intersections across the United States are described based on existing literature and recent field observations. A set of recommendations for addressing and improving channel stability at bridges is suggested, including: (1) controlling water and sediment discharges at the catchment level; (2) revegetating channel banks with woody vegetation; (3) reshaping the channel cross-section to a more stable, configuration; (4) removing disturbances from the stream channel, such as cattle and (5) using structures to control flow near channel beds and banks. The physiographic setting is a factor in the solution of at least the first three suggestions in this list. Attention to the physical characteristics of bridge-stream intersections in the various physiographic regions can lead to sustainable solutions for stabilizing channels at bridge-stream intersections.
All Science Journal Classification (ASJC) codes
- Environmental Chemistry
- Water Science and Technology
- Environmental Science(all)