The Mississippi Delta region was losing land
long before Hurricane Katrina came ashore. But the correlation between land
loss and the risk of flooding in the region is now more evident than
ever.         

The scientific community is not in harmony
about what mechanisms are most responsible for the land loss or what to do
about it, says Dr. J. David Rogers, the Hasselman Chair of Geological
Engineering at the University of Missouri-Rolla. Rogers will present some of
his ideas about the land loss problem during the Geological Society of
America’s annual meeting Oct. 28-31 in
Denver.         

Rogers’ presentation, “Geological factors
promoting ground subsidence and coastal land loss in the Mississippi Delta and
the great debate over what to do about it,” starts at 10:30 a.m. Wednesday,
Oct. 31, in Room 505 of the Colorado Convention
Center.         

Since 1950, the delta has been losing an
average of 55 square miles of land each year. That figure accelerated to 115
square miles of land loss the day Katrina struck.

Following the Katrina disaster, Rogers was
appointed to the National Science Foundation’s Independent Levee Investigation
Team. He is also a member of the Coastal Louisiana Recovery Panel, which is
charged with making recommendations for a new flood defense system. Among other
things, panelists are exploring ways to construct “green levees” by utilizing
soil reinforcement
technology.         

“We need to get away from old ideas and
systems of defense that have proven unreliable, and try to explore new
technologies,” Rogers says. “Some of the new infrastructure will be buried
beneath the river, and we’ll have to be opportunistic in diverting and managing
silt-laden flood waters. It’s going to require a higher level of management
than has previously been applied to the Mississippi River
corridor.”         

Rogersis focusing
much of his research energy on exploring viable methods to save some of the
millions of tons of silt that is being discharged into the Gulf of Mexico
instead of being deposited in the Mississippi River’s natural flood plain,
which covers a third of Louisiana.         

Since 1950, the delta has been losing an
average of 55 square miles of land each year. That figure accelerated to 115
square miles of land loss the day Katrina struck, according to
Rogers.         

In the past 100 years, sea levels have risen
about one vertical foot. Scientists estimate that levels will continue to rise
between one and three feet per century. Rogers says land loss in the region is
caused by many things, including silt discharge, drainage of old swamp and
marsh deposits, river management practices for increased navigation, commercial
development, and extraction of oil and
gas.         

In Denver, Rogers plans to describe 12 ways in
which the Mississippi Delta is sinking. He will also talk about some of the big
ideas for realistically countering the losses without alienating politicians
and direct
stakeholders.         

“Doing nothing isn’t an option,” Rogers says.
“The Mississippi River drains 41 percent of the U.S., and New Orleans exports
the largest bulk volume of goods of any port in the world, mostly food. You
can’t just shut it down. The economic impact would be
staggering.” 

Related Links

Q&A
with Dr. Rogers