The project includes a storm surge barrier along the edge of the peninsula with an elevation of 12-foot NAVD88. The height of the barrier would vary depending on the ground elevation. Areas that have lower ground elevations would tend to have more barrier visible. Areas with higher ground elevations would tend to have less barrier visible. Also, the experience of the barrier would vary depending on the barrier design. For example, in locations near the Low Battery (Figure 1) where the ground elevation is around 5-feet NAVD88 the visible barrier height is around 7-feet tall. However, because the barrier is designed for people to walk on it, the experience of the barrier is almost as though it has no height. The project team will be considering a similar structure along the west side of the Peninsula through the City Marina, Medical District and Brittlebank park.
Figure 1: Current aerial view of the rehabilitated Low Battery.
By providing coastal storm surge protection for the Charleston Peninsula, the project reduces risk of damage to aesthetic and cultural resources from these storm events. Simultaneously, the project team recognizes the design of the barrier will need careful attention to fit in. This is why the Chief’s Report for the project identified approximately $54M (est.) for aesthetic mitigation.
The project team, which includes the Corps and the City of Charleston, will work to preserve the aesthetics of the Peninsula while reducing the risk of coastal storm surge damages. The Corps and the City will work together on the design of the storm surge barrier, including the aesthetics, and have together developed and agreed to a Memorandum of Understanding (MOU) to guide the treatment of aesthetic resources.
The MOU states that during Preconstruction, Engineering and Design (PED), the project team will address aesthetic resources in the following ways:
• identify aesthetic resources and conditions,
• assess the nature and extent of effects on aesthetic resources,
• design the project for considerations such as compatibility, and
• determine any needs for additional mitigation.
The MOU includes public engagement as a part of the design process for aesthetics. The project team will design the project with aesthetic resources in mind and will share information and visuals with the public as they are developed. Figure 2 is an example of the kinds of design concepts that may be developed and shared with the public.
Figure 2: Example concept of a storm surge barrier at Joe Riley Waterfront Park. (Rendering Created By The City Of Charleston Civic Design Center)
The process for treatment of aesthetic resources under the MOU is in addition to the process in place for the treatment of historic and cultural resources (including visual affects to those resources).
The project team recognizes that the aesthetic resources in and around the Charleston Peninsula are a critical part of the community and addressing these resources with care is in the public interest.