The most comprehensive effort of coastal protection and restoration in Louisiana’s history may hit the state’s coastline within the year.
Kirk Rhinehart, chief of planning for the Office of Coastal Protection and Restoration, said his office will approve its final draft of the 50-year, $50 billion plan to restore the coast and submit it to state legislators by March 26.
That $50 billion will come from many sources, including BP, the Natural Resource Damages Assessment and the Clean Water Act, Rhinehart said. Those funds could account for tens of billions of dollars not currently appropriated to the individual Gulf States, he said.
Most of the proposed land building would occur through the diversion of the Mississippi and Atchafalaya rivers, the plan said. Sediment diversion is achieved by rerouting fresh water and sediment with new channels or structures.
School of the Coast and Environment professor Harry Roberts has conducted research on the successful sediment diversion in the Wax Lake Delta on the Atchafalaya River. Roberts said sediment diversion is the key to the level of coastal restoration the plan outlines.
These methods will slow land loss due to the rising global sea level, he said.
“We must use the sediment resources we have at hand in the most efficient way,” Roberts said in an e-mail. “The Wax Lake Delta is a good example of the land-building potential of river diversions. However, river diversions must be located where they will not only build new land, but also do the most good to enhance and maintain existing wetlands.”
But Eugene Turner, another professor in the School of Coast and Environment, said he is opposed to the use of diversions proposed in the current plan.
Turner has conducted research on three deltas in the flow path of diversions on Louisiana’s coast, the most notable of which is the Caernarvon Diversion on the Mississippi River downstream from New Orleans.
From what he observed at Caernarvon, Turner said the different types of soils already present in the delta are affected differently by water from upstream.
He said organic soils at the Caernarvon Delta developed over several thousands of years with very few nutrients from upstream. With the diversion came an influx of nutrients from farming communities upstream, which allowed wetland plants to survive without growing as extensive root structures.
The combination of the wetland’s less-developed root structure and the decomposition of the soil made it especially susceptible to land loss, Turner said.
“After Katrina, they lost 55 square miles in the flow path of the diversion,” Turner said, “One- third of the wetland. My interpretation was this loss was due to the nutrients in the river and flooding due to the diversion.”
Turner said he has voiced his concerns to the Office of Coastal Protection and Restoration several times and endorses the backfilling of canals as a safer, more cost-effective method to build land.
Christopher D’Elia, dean of the School of Coast and Environment, said most of the discussion he has heard regarding the plan has been positive, but that some dissension is customary.
“Anything you do will involve controversy,” D’Elia said. “There is always going to be an interest group negatively affected, just as interest groups will be positively affected.”
Rhinehart said the Office of Coastal Protection and Restoration does not consider the land loss at the Caernarvon Diversion to be applicable to the type of sediment diversions proposed in the current draft of the plan.
“The Caernarvon Diversion is not an analog or accurate comparison,” Rhinehart said. “The Wax Lake Delta is what we point to as a successful sediment diversion.”
He also said that projects of canal backfilling are smaller than the scope of the Master Plan.
The Office of Coastal Protection and Restoration values such contributions and has put a “huge emphasis” on reaching out to a vast portion of the state’s population affected by coastal land loss, according to Rhinehart. He said the office has worked to address the concerns of environmentalists while balancing the concerns of industry representatives that rely on Louisiana’s coastal economy.
“We understand that ours is a working wetland,” Rhinehart said. “It is not a petting zoo. This is not the Everglades.”
 
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Contact Paul Braun at [email protected]