Aeolian Processes, Coastal Dunes, and the Coastal Engineering Manual, Part III, Chapter 4 — ''Wind-Blown Sediment Transport''

Along many shorelines, the coastal foredune plays a key role in protecting against coastal flooding while providing a unique environment for specialized flora and fauna. Over the past 20 years, researchers with backgrounds in engineering, geography, geology, and geomorphology have expanded our understanding of the coastal aeolian processes that build and shape these landforms. In 2002, the U.S. Army Corps of Engineers (U.S.A.C.E.) replaced its Shore Protection Manual (SPM) with the Coastal Engineering Manual (CEM). The CEM is intended to provide "in a single source the current state-of-the-art in coastal engineering to provide appropriate guidance for application of techniques and methods to the solution of most coastal engineering problems", thus establishing it as the legal standard for coastal engineering practice in the U.S. Chapter 4 in Part III, "Wind-Blown Sediment Transport" is intended to provide engineers such guidance where wind blown sand is a part of the problem or the solution. This paper reviews Chapter III–4 and compares it to the published research to assess the degree to which this section communicates and codifies "state-of-the-art" understanding of coastal aeolian processes and landforms. Our review suggests that three specific areas require revisiting: (1) the "Transport Rate" section should be revised to direct the user to conservative transport rate estimation methods; (2) the coastal aeolian and dune process descriptions should be expanded to incorporate recent research findings, especially those that encourage and permit the engineer to incorporate more natural processes and landforms in solutions; and (3) an outdated and incorrect recommendation should be removed immediately.