Tag: #CW

Levee Systems in Louisiana

Published on by CWPPRALeave a comment

As flooding events continue to increase in frequency and intensity, it is essential for the State of Louisiana to continue moving forward in technology and ingenuity for the construction of levee systems.

Since 1718 natural and man-made levee systems in Louisiana have been crucial in attempt to control the “Mighty Mississippi”. The Mississippi River drains 41% of the continental U.S. and more than half of Louisiana’s land is in a flood plain [1]. Therefore, careful planning, construction and maintenance of levee systems in Louisiana must continue to improve.

What is a levee?

According to the Federal Emergency and Management Authority (FEMA) a levee is a “man-made design and construction in accordance with sound engineering practices to contain, control, or divert the flow of water to provide protection from temporary flooding [2].

Some History on levees:

Before European control, natural processes occurred along the Mississippi River in which sediment deposits created natural levees reaching up to a meter or two in height. [3]. Initially, state government required that farmers and land owners build their own levees with ~10-12 cubic yards per day and reaching 75 feet long in some areas [4].

Today, with multiple Acts by the United States Congress, levee systems are professionally implemented by multiple entities to promote control and prevent flooding.

Who is Involved:

There is no one entity solely responsible for levee construction and maintenance in Louisiana [2].  Some entities that share the responsibility include but are not limited to the following:

levee districts

Current Programs including Levee Development and Planning:

Necessary Plans for the Future:

The Louisiana Master Plan for a Sustainable Coast 2017 calls for project  “construction of a levee to an elevation of 15-35 feet around the Greater New Orleans area from Verret to the Bonnet Carre spillway” [5].

La_pic

Incremental Improvements recommended by David Muth (A Director of National Wildlife and Fisheries) include [5]:

  • Levee resilience
  • Increased water storage capacity inside levees
  • Public incentive to participate in building raising or relocation programs
  • Restoring the wetland buffers outside levee

A Plan in the year 2009 from Netherland Engineers to CPRA recommended the following [5]:

  • Raising levees to protect from a 500 year event or greater around central New Orleans
  • Raising levees to 1,000-year levels east of the Industrial Canal and on the West Bank.
  • Recommended a new levee and gates along the New Orleans land bridge, into St. Tammany Parish.

netherlands_rec

As flooding events continue to increase in frequency and intensity, it is essential for the State of Louisiana to continue moving forward in ingenuity for flood prevention, policy, planning, funding, and coastal restoration efforts.

Additional Links regarding Levees:

 

Work Cited:

[1] ALBL. “Association of Levee Boards of Louisiana”. 24 April 2018, http://albl.org/

[2] FEMA, “Levees – Frequently Asked Questions”.  24 April 2018, https://www.fema.gov/media-library-data/20130726-1803-25045-4819/st_broomelv.pdf

[3] Kemp, Katherine “The Louisiana Environment: The Mississippi Levee System and the Old River Control Structure”. 24 April 2018, http://www.tulane.edu/~bfleury/envirobio/enviroweb/FloodControl.htm

[4] Rogers, David. “Evolution of the Levee System Along the Lower Mississippi River”. 24 April 2018, http://web.mst.edu/~rogersda/levees/Evolution%20of%20the%20Levee%20System%20Along%20the%20Mississippi.pdf

[5] Schleifstein, Mark. “New Orleans area’s upgraded levees not enough for next “Katrina” engineers say”. 24 April 2018, http://www.nola.com/futureofneworleans/2015/08/new_levees_inadequate_for_next.html