NRDA Trustees should consider long-term sustainability of wetland creation projects

By Whit Remer, Policy Analyst, Environmental Defense Fund

In late April, the Deepwater Horizon Natural Resource Damage Assessment (NRDA) Trustees finalized the first phase of projects to address Gulf Coast environmental damage caused by the 2010 oil disaster. The trustees are a group of federal and state representatives charged with overseeing environmental restoration following the oil spill. The project document, known as the Deepwater Horizon Oil Spill Phase I Early Restoration Plan and Environmental Assessment (ERP/EA), comes on the heels of the draft version released in February for public comment.

The document includes a variety of projects across the gulf, including oyster restoration, wetland creation and improvements to public amenities. Rightfully, the trustees have considered a diverse suite of restoration options, and we encourage them to continue exploring the use of sediment diversions to achieve restoration goals in the Mississippi River Delta.

One of the most promising techniques for restoring, rebuilding and stabilizing wetlands in coastal Louisiana is the use of sediment diversions along the Mississippi River. Diversions replenish wetlands adjacent to the river with the fresh water, nutrients and sediments necessary to maintain healthy ecosystem functions. The State of Louisiana recently recognized the importance of such diversions in the 2012 Coastal Master Plan, which the State Legislature unanimously passed earlier this month. The master plan outlines a 50-year, $50 billion strategy to restore Louisiana’s coast and protect communities. Diversions are a critical component to achieving the long-term and comprehensive restoration envisioned by the plan.

The final Phase I ERP/EA includes the Lake Hermitage Marsh Creation project, a small-scale sediment pipeline project in Plaquemines Parish. The project will transport fresh water and sediment from the Mississippi River through a pipeline to wetlands adjacent to the river, and is expected to create over 100 new acres of marshland at a cost of $14 million. Pipeline projects have been effective in Louisiana in the past, but they do not provide the long-term sediment flow necessary to sustain the land-building functions needed to restore the coast.

The Lake Hermitage project serves as a good starting point for restoration in the Mississippi River Delta, but to achieve long-term restoration, wetlands need a constant source of sediment and nutrients that pipeline projects do not provide. Moving forward, we recommend NRDA Trustees consider actions that will promote the lasting sustainability of Louisiana’s coast. Without such actions, we may lose a unique opportunity to undertake comprehensive restoration.