|Shields Jr, Fletcher|
Submitted to: Management of Landscapes Disturbed by Channel Incision Stabilization Rehabi
Publication Type: Proceedings
Publication Acceptance Date: 4/15/1997
Publication Date: N/A
Citation: N/A Interpretive Summary: The collapse of unstable stream banks is a significant source of erosion in many agricultural watersheds. The sedimentation caused by bank collapse also tends to degrade aquatic habitats. Bank protection measures have the potential to preserve valuable agricultural lands and enhance aquatic habitats. A laboratory study was conducted to improve the design of spur dikes (a structure widely used to protect stream banks) to not only protec the stream banks, but also to maximize the volume of the scour pool formed by the structure. Stable pools are an important part of improving aquatic habitats in unstable stream channels. Watershed managers need this knowledge to design bank protection structures that improve the aquatic environment as well as protect the channel banks.
Technical Abstract: A series of experiments on the local scour of spur dikes with over-topping flows was conducted in a laboratory flume. Contraction ratio and flow depth were varied in the experiments and found to be positively correlated with the volume of the scour hole. Maximum scour depths measured in this study are closely comparable to those measured in other studies. The depth of flow relative to the height of the spur dike was found to be an important factor in the geometry of the resulting scour hole. Flow depths significantly greater than the height of the spur dike probably dominate the formation of stable scour pools in the field. These stable pools are important for improving aquatic habitats in unstable streams.