In-stream structures for thalweg management and bank protection

Authors: ETTEMA, ROBERT - Colorado State University; CROOKSTON, BRIAN - Utah State University; Papanicolaou, Athanasios

Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: 6/10/2024
Publication Date: N/A
Citation: N/A

Interpretive Summary: Throughout history communities have placed great accomplishment on the taming and conquering of streams and rivers. The Golden Gate Bridge, Boulder Dam, and the Tennessee Valley Authority projects are just a few of the success stories. However, the force of water does not always bend to man’s will. Streams and rivers naturally seek their own form, and successive years of powerful high flow events may destroy the glorious structures of men. While hurricanes and 100 year floods are high profile occurrences, more subtle problems are also present and must be handled. The scouring of bridge foundations and the unwarranted migration of streambanks can be subtle, yet damaging problems. These events place hardships on engineers, and landowners. This book chapter provides managers with the needed tools to address bank erosion and loss of fertile land.

Technical Abstract: This chapter describes the instream structures used to make a channel’s thalweg alignment acceptable and steady, as well as possibly protect a bank from the erosive power of water. Further, this chapter gives the recommended guidelines for the layout and dimensions of these structures, and it indicates the scour zone that these structures can develop. Scour can destabilize the structures. To be kept in mind is that, despite design guidelines being useful, an array of instream structures must fit a channel’s morphology to achieve the array’s purpose. This consideration can make an array of instream structures unique. Also, this chapter mainly concerns instream structures placed in non-navigable channels, although navigable channels are discussed briefly.