The Next 50 Years: Implementation of Coastal Master Plan projects
By David Muth, Louisiana State Director, National Wildlife Federation
Now that Louisiana’s 2012 Coastal Master Plan is law, it is critical that the state’s Coastal Protection and Restoration Authority (CPRA) moves the process forward as quickly as possible. While the plan lays out a series of projects for over its fifty-year timeframe, the actual sequence of projects has not yet been completely planned. The sooner CPRA can finalize this project list and timeline, the sooner vital construction and restoration can begin.
Several things are necessary for creating that list of projects. First is to carry out continued modeling to measure how projects and suites of projects will interact with one another. One example is looking at how a mid-Barataria 50,000 cubic feet per second (cfs) sediment diversion will interact with marsh creation projects in the middle Barataria Basin and with a ring levee and community resiliency measures for the nearby town of Lafitte.
Second is to work out how funding streams can be most effectively sequenced to begin building out the projects identified in the list. This is especially critical with Clean Water Act penalty funding to be distributed under the RESTORE Act and the separate Natural Resource Damage Assessment (NRDA) process. These funding sources, resulting from the BP Deepwater Horizon oil spill, could become available at almost any time over the next few years.
Third is to move quickly to implement nonstructural hurricane risk reduction measures. Nonstructural storm protection measures are those that build community resiliency by means other than “structural” methods such as levees, floodwalls and floodgates. They include raising structures and homes up out of danger, hardening infrastructure and assisting with voluntary relocation. Unfortunately, the suite of existing nonstructural programs is reactive: invoked after, but not before, a disaster. That has to be changed moving forward.
Another challenge concerns the Chenier Plain in southwest Louisiana. The key to long-term restoration in that area is to find ways to modify the hydrology of the area’s navigation system to prevent the continued influx of sea water into formerly freshwater marshes. Simple on paper, tricky in practice.
At an implementation level, two important capabilities need to be developed for the master plan to move forward. One is to demonstrate the feasibility of long-distance pipeline sediment delivery. Much of the Coastal Master Plan depends upon finding a viable way to move vast volumes of sediment many tens of miles through dredge pipes. We have a great deal of experience with relatively smaller scale projects for both marsh creation and barrier island restoration, but the master plan proposes projects that will be carried out on a much larger scale — moving material over much greater distances than ever before. While there seems to be no technical reason this cannot be done, actually doing it will be important for fine tuning the plan.
Similarly, we need to test and demonstrate a sediment diversion somewhere other than at the mouth of the Mississippi River. The very existence of southeast Louisiana proves that such diversions build land. We have extensive experience cutting artificial distributaries near the mouth of the river and letting them build land – from Cubit’s Gap and a dozen other cuts on the Mississippi below Venice to the Wax Lake Outlet on the lower Atchafalaya River. We also know that crevasses through the man-made levee system prior to 1928 moved vast quantities of sediment into the upper estuaries. But we have never deliberately designed and constructed a controlled sediment diversion, and we will learn a great deal more than modeling can tell us by actually doing it.
All told, the to-do list for Coastal Master Plan implementation seems long, but with RESTORE Act and NRDA fines on the way, we will have the funding to jumpstart restoration. Combine this funding with the proper planning and prioritization, and coastal Louisiana will take several steps closer to a more sustainable future.