Saturday, July 11, 2009

The real answer for Louisiana's coastline

The real answer for Louisiana’s lost coastline
By: Ken LaRive081009

Acadiana has been lucky with hurricane damage. There are others just twenty miles south who were devastated.

Looking at maps only ten years ago will show the amazingly fast erosion of our Louisiana coastline once giving us protection.

Many ideas have come forward, from the use of Christmas Trees to dredging up bottom sand, but the trend continues unabated.

There is an answer, but few want to consider it.

Coastline is maintained by sediment, mostly form the Mississippi River. Naturally, the Mississippi river changes course every few hundred years or so, diverting to the Atchafalaya.

A topical map indicates that water level is much shallower at the base of the Atchafalaya, and drops off sharply at the base of the Mississippi. With the Mississippi redirected, a good portion of the basin was washed away, quickly building and maintaining marshland, our primary protection from storm serge. After time, sediment built up to a critical point, and the Mississippi diverted back, as it has for millions of years.

The building of levies and inland canals inhibit the free movement of sediment too, showing another incompetent decision.

The answer is difficult to consider. Most of Morgan City would be washed away, and the port of New Orleans would be a quarter of a mile from what water was left, if any.

A lot of very expensive studies have formulated many scenarios, but this idea is hardly mentioned.

Another, post Katrina feasibility study, as most will agree, must weigh cost as the primary consideration, as hurricane damage is now approaching the price of a new port, and the loss of a major town.

Whatever the decision, it would indeed be an expensive proposition, and it is one that grows more serious as it is set aside.

No comments: