Historic Flood of 2011?

I grew up in southern Louisiana and always knew about the levees, however, I never really understood what they were for until recently.  As has been detailed in the news many communities along the Mississippi River have been experiencing serious and devastating flooding.  That flooding is moving south towards Louisiana.  The Mississippi River is swelling and threatening to overflow its banks in both Baton Rouge and New Orleans and as a result could destroy many of the homes and businesses.  That's where the levees come in.

Years ago the Army Corps of Engineers built a series of control structures to help ease the burden of flooding presented by the Mississippi River.  There are 3 main structures which when opened help divert water out of the Mississippi River and into other areas.  The first 2 structures, Old River Control Structure and Morganza Spillway, allow water to flow into the Atchafalaya Basin.  The 3rd structure, Bonnet Carre Spillway, is located near New Orleans and allows water to flow into the Lake Pontchartrain.  If water is allowed to flow in the Atchafalaya Basin it will flood many farms and possibly some communities.  The water won't just flow anywhere though.  It will flow towards the Gulf of Mexico and the levees help it to stay in line on its way without spreading out to other communities.  The levees are parallel to each other forming a wall to keep the water in on its way south.

It's possible that as early as tomorrow afternoon (Saturday, May 14th) the Morganza Spillway will be opened allowing the water to flood into the basin.  This will cause the people of the area to sacrifice their land to save those in Baton Rouge, New Orleans and areas in between.   No matter what happens though this flood appears to be of historic proportions.

I feel for the people in these areas that will be flooded and for those that have been flooded already.  One thing natural disasters like this reminds us of is that nature can't always be tamed.  The Mighty Mississippi will ultimately do what she wants.  Much like the constantly shifting sands of the Outer Banks in North Carolina.

I found the following blog entry titled "High Water" very helpful in visualizing how the control structures work and where they are located:
http://www.workingdefinition.com/2011/05/06/high-water