Road to Restoration: Assessing the Damage to Shorelines
The Gulf of Mexico supports more than half of the wetlands in the United States â in fact, more than 40 percent of the wetlands in the lower 48 states are in Louisiana alone. These and other shoreline habitats, including marshes and mangroves, are home to birds, fish, and other wildlife. These areas are being lost at a rapid rate in the Gulf due to storms, erosion, sea-level rise, and other factors.
When the Deepwater BP spill occurred, our leaders were concerned that the oil leaking into the Gulf would cause the most damage along these sensitive shorelines. Responders placed boom along extensive stretches of the coast to prevent oil from reaching land. But some oil that wasnât captured was churned by wind and waves into a brown, foamy âmousseâ that reached some shorelines. Oil also reached the shore in its natural form, causing a slick along certain beaches and coating vegetation.
When oil seeps into shoreline marshes and other areas, it can âsmotherâ the grasses and other plants living there, stunting their growth or even killing them. Without the plant roots to hold the soils together, the marsh might be at risk of accelerated erosion from waves and storms. Oil on shorelines can also seep into the sediment, where it is difficult to remove.
NRDA teams have worked to document the severity, extent, and duration of shoreline oiling. We have conducted aerial surveys via helicopter and dispatched teams to walk the beaches to photograph and measure oil in sediment and soil. As of late April 2011, teams had surveyed about 4,300 linear miles of shoreline and documented more than 1,050 total linear miles of oiled shoreline. They reported that mostly light oil or tar balls persisted on more than 500 linear miles of shoreline.
The information from the surveys is being used by the co-trustees to develop restoration plans for shorelines. Potential projects could include replanting marshes and creating or protecting additional marshland to restore for the benefits that were lost while the marsh was oiled.