The Convergence of Science and Engineering for Sustaining Coastal Landscapes – Case Study: Louisiana's Comprehensive Master Plan for a Sustainable Coast
Following the devastating impacts of Hurricanes Katrina and Rita, the State of Louisiana assembled experts in coastal restoration as well as transportation and levee specialists to develop the first fully integrated plan to save coastal Louisiana in history – Integrated Ecosystem Restoration and Hurricane Protection: Louisiana's Comprehensive Master Plan for a Sustainable Coast. The plan is a paradigm of cooperation, employing a comprehensive, systems approach to protect Louisiana's coast, its population, vital infrastructure, and habitat in a place of world ecological significance. The Comparative Urban Studies Project and the Environmental Change and Security Program co-hosted a seminar on "The Convergence of Science and Engineering for Sustaining Coastal Landscapes – Case Study: Louisiana's Comprehensive Master Plan for a Sustainable Coast" to discuss the development of the plan and its implications for the future of the region.
R. King Milling, Chairman of America's WETLAND Foundation, spoke about the significance of the Mississippi delta and southern Louisiana - the largest and most complex ecosystem in this country. An area of swamp, marsh and forest covering 4 million acres and constituting 43% of the coastal saltwater marsh and 25% of the freshwater marsh in the lower 48 States, the delta ecosystem is key to the vitality of the area; homes, business, churches, and billions of dollars of infrastructure all rely on the resources and protection provided by the delta. Human interference in this ecosystem, however, has led to severe losses of land. Man-made levees built to protect the region's inhabitants from flooding and maintain navigation routes have deprived the ecosystem of its natural processes. Constant loss of sediment, eutrophication, the construction of navigation canals, and oil and gas exploration have led to the loss of 2000 square miles in the last 75 years, with the projected loss of 500 square miles in the next 50 years. Milling highlighted several reasons why we need to restore the delta: as one of the world's most diverse and productive ecosystems it is an environmental treasure; it is a working ecosystem on which over 2 million people, historic and strategic cities, and billions of dollars of infrastructure depend; the entire country relies on the region for fish, oil, gas and navigation routes.
Sidney Coffee, Chair of Louisiana's Coastal Protection and Restoration Authority (CPRA) and Executive Assistant to Governor for Coastal Activities, stressed the need for a national commitment to the restoration and protection of the Mississippi delta. Indicating the magnitude of Hurricanes Katrina and Rita's impact on the coast, Coffee underscored the sense of urgency surrounding coastal restoration. In 1990 the Coastal Wetlands Planning, Protection and Restoration Act ("The Breaux Act") brought together five federal agencies and the state in a mandated restoration effort, providing the first stable source of federal funds dedicated to coastal restoration. Following the hurricanes, Louisiana expanded the State Wetlands Authority to create CPRA, mandated to both create a comprehensive coastal master plan that addresses the situation from a program approach and to oversee all the levee districts in south Louisiana, viewing coastal restoration and hurricane protection comprehensively.
Coffee discussed the financial limitations of the project, detailing the dedication of all future Outer Continental Shelf (OCS) oil and gas activity revenues to the protection and restoration of the coast beginning in 2017. The objectives of Louisiana's Comprehensive Master Plan for a Sustainable Coast are to reduce risk to economic assets; restore sustainability to the coastal ecosystem; maintain a wide and diverse array of habitats; and sustain Louisiana's unique heritage and culture, Coffee concluded.
Dr. Robert Twilley, a Professor in the Department of Oceanography and Coastal Science at Louisiana State University, spoke next about the science and engineering application to coastal restoration. Discussing the different natural systems in the coastal region of Louisiana, Twilley explained that the river-dominated delta is made up of sand, sediment, and salt. Different stakeholders have varying opinions about how to best deal with each element.
Twilley gave an introduction to the geology of the region, stressing that the geomorphology of the system drives the ecology; hence, you must restore the geomorphology to restore the ecology. Twilley highlighted three engineering solutions, each with its own set of challenges:
1. The ability to actually understand the context of what is being restored and scale up the engineering capability so that it can match the tremendous change needed.
2. Structure vs. non-structure landscape features – In addition to levees, it is important to use wetlands as part of the landscape protection.
3. Eutrophication, caused by a building up of nitrate at the center part of the river basin from agricultural lands, could potentially shut down the river management system even while steps are taken to reduce salinity by adding freshwater into the river system.
Dr. Donald Boesch, a Professor of Marine Science and President of the Center for Environmental Science at the University of Maryland, concentrated on the need to integrate flood protection, hurricane protection, and coastal restoration into a comprehensive plan. Ecosystem protection, the functions of the Corps of Engineers, oil and gas infrastructure, and other types of transportation systems must all be accounted for in the plan as well. The most important objective is the maintenance of a sustainable coastal landscape, without which nothing else is possible. The Corps of Engineers has been working on a plan markedly different from the plan proposed by CPRA. While the state is looking at the situation conceptually, the Corps is taking a more detailed approach that may not be as effective.
Louisiana is the only state dealing with this particular plan, thus avoiding cross-state negotiations and coordination, Boesch noted. In addition, they have been granted significant recognition as a vital priority and have the chance to put into practice the new notion of "adaptive management".
Drafted by Lauren Herzer.
Professor, Marine Science & President, Center for Environmental Science, University of Maryland
America's WETLAND Foundation