ENGINEERING WITH NATUREÂŽ TO PRODUCE HORIZONTAL LEVEES
Horizontal Levees offer a unique opportunity to create additional benefits in association with traditional approaches to Coastal Storm Risk Management (CSRM) projects. Rather than relying on the steep slope of a traditional levee system, these levees consider a more flat slope of added sediment — an augmentation to the traditional levee footprint. The resulting grade allows for high and low marsh plants to recruit, thereby colonizing the toe of the levee. The complementary addition results in wetlands that support the levee structure, further reducing wave impacts. The Sabine Pass to Galveston Bay CSRM and Ecosystem Restoration Project proposes an extensive network of levees and flood walls as part of the overall flood-risk reduction strategy. Orange County, Texas, is located in the study area, where 15.6 miles of traditional levees and 10.7 miles of flood walls are proposed. In this area alone, integrating 2.6 miles of horizontal levees would create more than 100 acres of new marsh habitat in locations where hundreds of acres of fragmented and/or degraded marsh currently exist that would benefit from this action. Nearby residents would be able to access the levee feature for birding, walking and other recreational activities. Dredged sediment derived from navigation channel maintenance would be used to construct the levees, offering a much improved method for managing sediment resources within coastal systems.
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