Stakeholders’ Vision Guides Engineers’ Plans
Congress to the Corps: Plan for Category 5

Following the twin hits of hurricanes Katrina and Rita, the plight of Louisiana seized the attention of the nation.

From California to Minnesota to Maine, people were talking about the importance of Louisiana’s coast. And in Washington, Congress took action, directing the U.S. Army Corps of Engineers to develop a plan to protect Louisiana’s coastal area from fierce Category 5 hurricanes.

The Corps, in coordination with Louisiana’s Coastal Protection and Restoration Authority and assisted by leading experts and engineers worldwide, is analyzing and designing a full range of flood control, coastal restoration and hurricane protection measures for coastal Louisiana. Integral to their planning efforts is the participation of residents and other stakeholders explicitly describing the future they want for Louisiana. Twenty million dollars in federal monies fund the effort, known as the Louisiana Coastal Protection and Restoration project (LaCPR).

A Strategy for Coastal Protection

An initial task of the LaCPR team was to establish what levels of protection against storm damage the plan should provide to ecosystems, communities and infrastructure in all regions of the coastal area. The project also had to determine what storm conditions the plan should protect against, as the Saffir-Simpson Scale for categorizing hurricanes does not assess all potentially damaging factors, such as a storm’s track or height of surge. To assist stakeholders in determining their levels of risk tolerance and evaluating the relative merits of alternate plans, the Corps is using a risk-based methodology to describe the likelihood of different storm scenarios, analyze the efficiency and effectiveness of possible risk reduction measures and compare their costs.

Workshops early in the plan’s development emphasized the importance of integrating coastal ecosystem restoration and engineered flood protection. Neither without the other can adequately protect Louisiana’s people, culture, economy and environment.

“Although new technology may develop, sustaining the coast does not necessarily require new restoration techniques,” says Dr. John Lopez, representing the Lake Pontchartrain Basin Foundation in the plan formulation workshop. “Rather, it requires a new strategy to coordinate and prioritize conventional restoration methods and projects for coastal habitats.”

Gregory Miller, a Corps project manager for the LaCPR Report, concurs: “The Corps of Engineers has embraced the multiple lines of defense strategy for protecting the Louisiana coast and its communities. The lessons of Hurricane Katrina show that a leveesonly approach will not work. Restoring the wetlands that separate our cities from the sea is crucial for our long-term survival.”

Adjusting priorities may alter the likelihood of building certain proposed projects or increase the scope of some existing projects. Restoration methods favored to achieve comprehensive coastal protection include expanding the beneficial uses of dredged materials and increasing the number and size of sediment delivery projects. Many scientists believe large-scale river diversions are essential if the Louisiana coast is to achieve long-term sustainability.

Approaching Old Problems with New Thinking

Some of the challenges of designing comprehensive coastal protection are as old as Louisiana’s first earthen levees: poor soil foundation conditions, high subsidence rates, sea-level rise and the unknown effects of future storms. Yet today’s engineers are confronting these challenges with new materials, new methods and new thinking.

For example, building a 40-foot-high barrier to storm surge would require a levee footprint and stability and wave berms approaching 1,000 feet in width. Made of conventional materials — earth, steel and concrete — such a barrier could easily be too heavy to construct on Louisiana’s compacting soils.

Yet the benefit of a 40- foot-high barrier is evident to many of Louisiana’s communities. The LaCPR project has encouraged engineers to devise ways to improve foundation conditions, construct barriers with lightweight materials, and design new barrier configurations to address the challenges of conventionally engineered hurricane protection. The plan will incorporate such innovative thinking, as well as fresh approaches to using the landscape for protection. An integrated system combining physical barriers, environmental features, and operation, maintenance and quality assurance programs will provide Louisianans the protection they desire.

Six-month and 24-month Benchmarks

In the summer of 2006, the Corps of Engineers submitted its Preliminary Technical Report to Congress. The report, available at http://lacpr.usace.army.mil, summarizes work on the plan to date and includes reports from workshops, public meetings and peer reviews.

Outlining a strategic approach, the Preliminary Technical report considers key factors for completing the Corps’ full plan, such as enhancing coastal features that reduce storm surge, identifying hurricaneinduced threats to New Orleans, exploring potential technical collaboration with Dutch scientists, promoting storm-resistant domestic architecture, and determining coastal engineering design challenges.

To produce the final technical report, due to Congress in December 2007, the Corps will analyze and refine the design of the alternative plans under consideration. The Corps will continue its coordination with other planning activities and involvement with stakeholders through community meetings and public comment. Louisiana doesn’t have to wait for the final report, however, before components of the comprehensive protection plan are recommended for authorization; requests for Congressional authorization of projects or for funding to advance promising concepts may be submitted at any time.