Section 3: Coastal Engineering, Mitigation and Societal Response to Coastal Hazards

Overview

Section 3 explores hard shoreline mitigation strategies, their impacts to coastline erosion, and introduces alternative mitigation approaches using soft engineering methods and material. The unit introduces the concept of layered defenses, their direct benefits and how these strategies mitigate risk, and in the last module the concept of smart building or building with nature is explored. The unit consists of three modules:

• Hard Structures and Coastal Modifications through Mimicking Natural Processes (Module 7)
• Managed Retreat/Multi-Layered Protection (Module 8)
• Smart Building (Module 9)

These modules consider how policy makers and city planners can use this information to determine which measures minimize coastal hazards and erosion by establishing sediment continuity and therefore function , which methods (hard of soft) are most suitable for protecting coastlines, and learn the concept of layered protection as an innovative and smart way to protect against future hazards.

Section Goals

Upon completion of section 3 you will:

• analyze variability of coastal erosion and accretion rates at natural settings as well as at location proximal to hard engineering structures
• explain and contrast innovating approaches to coastal hazard mitigation
• analyze new concepts of mitigation such a layered defenses, smart building and building with nature as sustainable mitigation practices

Section Objectives

In order to reach these goals, the instructors have established the following objectives for learning. In working through the modules within section 3, you will be able to:

• analyze differential erosion by utilizing geospatial tools and sequential images
• investigate alternative methods for non-structural shoreline hazard mitigation, including managed retreat and multi-layered defenses.
• explore the pros and cons, including cost-benefits of managed retreat case-studies and consider examples of communities facing retreat as an option and the factors leading to these decisions.
• analyze hypothetical storm surge impacts on communities on the Louisiana coast from Google Earth and online tools.
• implement smart building approaches to aid in the expansion of one city that is threatened by sea level rise and storms, and employ building with nature and layered defense approaches in the design.
• integrate concepts of resiliency and coastal flood protection through massive nourishments, and how these new methods are setting trends in smart building along coastlines.

Assessments

Learning check questions will evaluate your understanding of the key concepts for each part of this section's modules. Activate your learning questions will extend the core module content through external readings and data sets, and will help you engage with the material. These questions are asked for your benefit; you are encouraged to answer them, since they frequently introduce methods and applications that you will need to use again during graded assessments. All modules also contain formative assessments, which are similar to activate your learning questions but are usually longer and more complicated, and are also graded. At the end of each module you will be asked to complete a graded summative assessment. In module 7, you will calculate erosion rates using sequential images, analyze the effects of hard structures such as groins on shoreline position, and establish new protection practices for already vulnerable sites on the west coast of US. In module 8, you will analyze hypothetical storm surge impacts of communities in Louisiana as a function of shelf slope, wind speed and fetch, and in module 9 you will first protect a city that needs to expand to do so by using a smart building, layered defenses approach, and then evaluate the benefits of building with nature such as by employing massive nourishment projects.

• Module 7: Hard Structures and Coastal Modifications through Mimicking Natural Processes
• Module 8: Managed Retreat/Multi-Layered Protection
• Module 9: Smart Building