Free Newsletters - Space - Defense - Environment - Energy - Solar - Nuclear
..
. Earth Science News .




SHAKE AND BLOW
New Notre Dame study proposes changes in New Orleans area levee systems
by Staff Writers
Notre Dame IN (SPX) Jul 26, 2013


File image.

Less may mean more when it comes to the levee systems designed to protect New Orleans from hurricanes.

That's the conclusion of a new study by a team of University of Notre Dame researchers led by Joannes Westerink, co-developer of the authoritative computer model for storm surge used by the U.S. Army Corps of Engineers, the Federal Emergency Management Agency (FEMA) and the state of Louisiana to determine water levels due to hurricane surge and to design levee heights and alignments.

The lower Mississippi River south of New Orleans protrudes into the Gulf of Mexico and man-made levees line the west bank of the river for 55 kilometers of what is known as the Lower Plaquemines section. There are no levees on the east side of this stretch of the river. Westerink points out that, historically, sustained easterly winds from hurricanes have directed storm surge across Breton Sound into the Mississippi River and against its west bank levees.

"This study clearly shows that the man-built west bank levee on the lower Mississippi River enhance the capture storm surge by the river, " Westerink said. "The surges are generated by the prevalent easterly winds that are common for regional hurricanes, but they spill into the river. These surges then propagate upriver endangering New Orleans from the river side."

As an alternative, the study shows that the lowering of man-made levees along the Lower Plaquemines river section to their natural state, to allow storm surge to partially pass across the Mississippi River, will decrease storm surge upriver toward New Orleans.

"By eliminating the 55 kilometers of man-made levees on the west bank of the river from Pointe a la Hache and Venice, the surges propagating in the river from Pointe a la Hache past New Orleans will be lowered by up to two meters," Westerink said. "This would save billions of dollars in levee construction to protect communities upriver from Pointe a la Hache."

The study also shows that the size of surges captured by the river actually decreases with a high stage river.

"While higher flow and stages on the river do cause the storm surge to rise on top of the river water levels, causing overall higher water levels for a specific hurricane, the storm surge does not simple linearly add to the pre-storm river water levels," Westerink said. "In fact, the surges captured by the river reduce as the river water levels rise."

The researchers are aware that eliminating the man-made levees on the west bank might potentially endanger the few sparsely populated areas along the lower west bank of the Mississippi.

"For the few communities south of the Pointe a la Hache, the study suggests building strong and high ring citadel levees around them and then connecting these communities with a bride, much as the Florida Keys are," Westerink said.

The researchers note that, historically, the design of Southeast Louisiana's hurricane flood risk reduction system has hinged on raising and adding levees in response to river or hurricane events that impact the region. Now, it may be time to think and build smarter.

"The study suggests building smarter citadel flood protection systems in the delta instead of long north-south linear systems that follow the river," Westerink said. "This reduces flooding risk, works with nature in that sediments can get to the delta from both the river and from hurricanes and thus build up the delta, and reduces levee construction costs by billions," Westerink said.

The group's study appears in the Journal of Waterway, Port, Coastal and Ocean Engineering.

.


Related Links
University of Notre Dame
Bringing Order To A World Of Disasters
When the Earth Quakes
A world of storm and tempest






Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle




Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News





SHAKE AND BLOW
Lourdes closed, 200 evacuated after flash floods
Toulouse, France (AFP) June 18, 2013
French authorities Tuesday shut the grotto at Lourdes and evacuated about 200 people following flash floods at the Roman Catholic pilgrimage site. The preventive measure came a day after heavy rain and unseasonal snowfall in the area led to rivers flowing well above their normal levels, even cutting off some roads. "The Sanctuaries are closed," the local prefecture of the Haute-Garonne a ... read more


SHAKE AND BLOW
Malaysia says will get tough on illegal immigrants

More steam in Fukushima reactor building: TEPCO

Fukushima steam still baffling: TEPCO

The best defense against catastrophic storms: Mother Nature, say Stanford researchers

SHAKE AND BLOW
Perfecting digital imaging

Ancient technology for metal coatings 2,000 years ago can't be matched even today

Controlling friction by tuning van der Waals forces

Carnegie Mellon, Microsoft researchers demonstrate internal tagging technique for 3D-printed objects

SHAKE AND BLOW
Newly discovered marine viruses offer glimpse into untapped biodiversity

Study explains Pacific equatorial cold water region

Carnegie Mellon-Developed Chemicals That Break Down Water Contaminants Pass Safety Test

NUS researchers developed world's first water treatment techniques using apple and tomato peels

SHAKE AND BLOW
Ancient ice melt unearthed in Antarctic mud

Coastal Antarctic permafrost melting faster than expected

New iceberg theory points to areas at risk of rapid disintegration

Arctic methane breach an 'economic time bomb'

SHAKE AND BLOW
Climate Forecasts Shown to Warn of Crop Failures

Secret of plant geometry revealed

World changing technology enables crops to take nitrogen from the air

Western demand for cashmere said a threat to endangered Asian species

SHAKE AND BLOW
New Notre Dame study proposes changes in New Orleans area levee systems

Tropical Storm Dorian forms in Atlantic

Rescuers battle to find China quake survivors

Quake shatters migrants' dream of better life for son

SHAKE AND BLOW
Covert U.S. flights could signal new Somalia action

Post-mortem on French operation in Mali

Nigeria to withdraw some troops from Mali

Climate change to hit Volta Basin for energy, farming

SHAKE AND BLOW
Extinct Ancient Ape Did Not Walk Like a Human

Japanese women retake top spot for life expectancy

Archaeologist says he's uncovered King David's palace

Brain signal said to create inner 'voice' we hear even if we're silent




The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement