Modernization of flood insurance risk assessments, ending of mandatory policies behind levees recommended ~Mark Schleifstein
~Commenter johnbgood~ "The
modern methods would be similar to those the Army Corps of Engineers
used in determining the risk of hurricane storm surge and rainfall
flooding as part of its design of levee improvements in the new Orleans
area after Hurricane Katrina."
Please do not use that flawed
methodology as the standard. There were too many things done wrong by
the Corps on that study. The Corps and all of its PR-engineers will
state at every public meeting that 152 storms were modeled for the
system in New Orleans. But in reality very few have even looked at the
modeling and even fewer of the Corps' PR-engineers even understand the
modeling they are referencing. The Corps model of 152 storms had many
many short-comings. Of the 152 storms, only about half of the storms
come within 60 miles of New Orleans. The model does not account for
slow moving storms and weak storms. The model under estimates the
relative sea level rise. The model under estimates the rate of
overtopping. Modeling for a deltaic coast is very complex. The Corps
has never stated what was the coastline they assumed in their model.
When all of these factors are combined, we have a model that does not
relfect the actual flood threat, but is nothing more than a academic
exercise in statistics and mathematics. And in some cases even a bad
academic exercise. For example, the Corps used the methodolgy to use a
small sampl size of storms to model the so-called 100-year flood. Then
used the same data to identify the 500-year flood level. The only
problem, is the data cannot be manipulated like the Corps did and have
any validity. If the 500-year level needs to be determined, then the
data used needs to be for the 500-year event not extracted from the data
set for the 100-year event and projected to create a so-called 500-year
event. That's just bad science.
And to show just how slow
things move to correct the flaws. To date the Corps has yet to run and
release the version of their model that includes all of the levee
improvements made since Katrina. I wonder why.
count on oversight by state agencies. Many of the seats on the boards
tasked with oversight, are filled by individuals with no technical
background to either understand or review the information they are
tasked with over seeing.
The real truth will not come out any
time soon because if it did flood insurance rates across the
metroploitian area (including the areas behind the levees) would sky
rocket. And the business leaders that pull the strings of the elected
officials will not let that happen. Because if it did, they would
probably lose employees and customers who would relocate to less flood
prone areas and their businesses would suffer.