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THE LOST MARSH

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I am not a scientist or hydrogologist I have a GED diploma and am a heavy equipment operator by trade. What I do have is experience working on jobs seeing what water can do and the memories of what the marsh and lakes looked like 30 plus years ago.
Once the levees cut off the sediment that built our solid ground near the river, which transitions to tree filled swamp then praries and marsh, the only land that continued to build is the delta at the mouth of the river.
I also witnessed the never ending erosion caused by digging of numerous oil production canals, the MRGO, and the Houma Navigation canal and the exagerated destruction from hurricanes they caused. These man made openings allowed saltwater to flow in and out of our marshes and to eat away at what we have. The smaller canals slowly ate away at the marsh, but the MRGO and the Houma Nav allowed massive amounts of water to travel further inland and to affect every bayou and drain in the marsh accelerating erosion.
Today we find ourselvs with years of destruction and we need a way to STOP it before we think about getting back what we lost.
There is a huge debate about diversions for and against. Some argue about what we will lose (salinity) affecting oysters fish and shrimp. Others say sediment will rebuild marshes.
I live near the Bonnet Carre Spillway and when it is opened the river overflows its banks it deposits sediment between the river and the Airline Hwy just as it did before the levees were built. This only happens between the upper and lower guide levees of the spillway because if not for these guide levees, the water would flood the surrounding communities. That being said Why not remove a portion of the guide levee north of the hurricane protection levee on the New Orleans side of the spillway allowing the water to filter through the swamps and marsh of the Labranch Wetlands depositing nutrients before entering Lake Pontchatrane just as it did before the levees were built, this would ease the problems of algee blooms in the lake. (I guess it would be too easy and cost effective.)
The example of the Bonnet Carre mimics what mother nature did before the levees, sediment deposited adjacent to the river nutrients filtered through marshes. This being said many small diversions along the river into fresh or brackish marsh would supply nutrients and fresh water to reverse the effects of salt water intrusion. Sufficient sediment fron a diversion will not travel far enough to rebuild marsh in the lower portions of the estuary.
Now for the costal marshes which I will compare to a man whose arm was torn off and eaten by a bear. It is gone and you are not going to get it back the most important thing to do is stop the bleeding! In addition to dredging to rebuild the barrier islands we also need to build up the outer fringes of the marsh to stop erosion from wind and waves. While using dredged material to build up the marsh some of the massive openings caused by years of erosion need to be filled in to slow future erosion from tidal flow.
The dam in the MRGO addressed that problem now the Houma Nav needs work. I know it will not be closed but a set of locks or structure to narrow its opening and reduce amount of water flow near Cocodrie would slow the erosion process to areas to its north.
In Plaquemine Parish massive amounts of sediment dredged from the river to keep the channel open could be piped northerly to build up what remains and to hold on to what we have.
As I said at the beginning I have no scientific degrees only memories, years of observation, and like everyone else an opinion.
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