Updating technology and systems could save lives and help lessen the financial ruin caused by floods.

Loss of life and destroyed property could be
avoided if the Federal Emergency Management Agency replaced current
flood maps with ones containing high-resolution land surface elevation
area — and if the agency used up-to-date modeling techniques.

So says a new FEMA-commissioned report from the National Academy of
Sciences/National Research Council. Peter Sheng, a University of Florida
professor of coastal engineering, was one of the chief scientific
contributors to the report published late last week.

"We're calling for new maps, and we're also calling for FEMA to update
their technology," Sheng said. "Their current methodology is getting
very old."

FEMA uses flood maps to set flood insurance rates, regulate development
and inform those who live in the "100-year" floodplain of potential
hazards. FEMA's Map Modernization Program of 2003 to 2008 resulted in
digital flood maps for 92 percent of the continental U.S. population.
Most live in areas that had outdated or no maps.

However, after a $1 billion investment, only 21 percent of the
population has maps that meet all of FEMA's data quality standards, the
National Research Council reported.

For this reason, FEMA and the National Oceanic and Atmospheric
Administration asked the research council to examine the factors that
affect flood map accuracy. FEMA also sought to assess the costs and
benefits of producing more accurate maps and find ways to improve
mapping and management of flood-related data.

In response, the research council committee, the NAS Committee on FEMA
Flood Mapping Accuracy, collected and analyzed information on selected
streams in test states of Florida and North Carolina and on the economic
costs and benefits of creating new digital flood maps in North Carolina.

The committee's report concludes that the costs for improving flood maps
— including analyzing flood-related data and updating regulations —
would be outweighed by benefits.

These include not only more accurate flood maps, which would help reduce
loss of life, property, and businesses, but also more efficient planning
and response for emergency services and preservation of natural
functions of floodplains.

Sheng said the 13 committee members spent two years researching the
material that went into the report's conclusions. His responsibility, he
said, was to produce the section on coastal flood mapping. He concluded
that FEMA, which continues to use flood modeling methods rooted in
1970s-era research, needs to modernize. 

"Academics have developed new models and new technologies that lead to
more accurate predictions," he said, adding that the agency currently
uses a simple, one-dimensional model to forecast wave action combined
with storm surge. "We are recommending that they start doing a
two-dimensional surge-wave model," he said.

He said the updated models will not necessarily cause flood zones to
grow or shrink, but rather that predictions will be more accurate.

"The uncertainty comes from the topological data and the way you do
modeling, and we are trying to remove the uncertainties," he said. "In
some places, the projected flood levels could go higher, while in other
places, they might go lower."

Sheng is a veteran researcher in the field of flood and storm surge
research and modeling. Among other efforts, he heads a Florida Sea
Grant-sponsored project to test a new storm surge modeling system in
Florida. He is leading experiments on storm surge and inundation models
for National Oceanic and Atmospheric Administration, and co-developing a
regional storm surge forecasting system for NOAA and the Office of Naval
Research.