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I need some assistance

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We are doing a project for FEMA where we are developing the flood module
for FEMA's HAZSUS software.  As a quick explanation, HAZSUS is a lost
estimation software developed for planning purposes.  The software is
designed with three levels:  Level 1 is all default information, and
scenarios can be run for anywhere in the United States; Level 2 the user
can use local data which is more accurate (such as assessors' data which
addresses specific buildings, etc.);  Level 3 the user can use any
dataset they have and the damage functions can be modified to fit
specific communities.  HAZSUS is currently available for seismic only.
Under development is the flood module and a hurricane module.  The
hurricane module will eventually be expanded to include all kinds of
wind events.

We are getting ready to test the models and data we have selected.  The
tests will take place in six communities throughout the United States.
Our first community is San Diego.  The building inventory we are using
is similar to that used by the earthquake module except it is at a lower
level.  HAZSUS earthquake uses building information at the census tract
level;  we are taking the flood module to the census block level.
HAZSUS earthquake defines 36 structural types to determine earthquake
losses.  For floods the framing system is not that critical.  Census
data gives gross area of buildings without consideration to structure
type, number of stories, or occupancy.  We need to develop regional
factors to define structure type as well as several other pieces of
information which are important to flood.

My request to you is to act as "local experts."  For those of you who
live or have done a significant amount of work in southern or northern
California please respond to these questions as best you can.

1.  For for all buildings, what is the distribution (in percent) of the
following structure types:


steel (specific framing system is not material)



2.  For residential structures what is the percentage of basements?

3.  For residential structures what is the percentage of crawl space
(elevated first floor)?

4.  For residential structures what is the percentage of slab on grade?

5.  For commercial (anything that is non-residential) structures what is
the percentage that are 1 to 4 stories?

6.  For commercial structures what is the percentage that is 4 to 10

7.  For commercial structures what is the percentage that is more than
10 stories?

The percentages reported should be total for the region.  We are asking
for information on southern California (San Luis Obispo south) and
northern California (north of San Luis Obispo).

If this approach is successful for our first proof of concept community
(San Diego County) we will then expand this request for each state in
the United States.  Our plan is to take your responses and plot them
(they should fall on a bell curve) and pick the result that fall within
whatever margin of error we determine will be reasonable.  Those
percentages will then be applied to the inventory which we have.  We
will check our damage functions (based on building use, height, and
structure type) and compare them to actual damages from past floods.  As
a check for our regional distribution of the above considerations, we
will check with the building departments within the specific county and
cities to see what they determine the distribution within their
community to be.

Your participation in this process will be greatly appreciated and will
be noted in our final report to FEMA and NIBS as to who the "local
experts" were.  The reference will be to the SEAINT list server.  Since
we are ready to begin our analysis on San Diego County, your responses
would be appreciated as soon as possible.  We will need to cut off the
responses as of 12/23/98 so we have time to plot them and perform the
appropriate statistical analysis.

I will be happy to post the results of this request once the responses
have been received.  In advance, I thank you for your time and
consideration in this request.  Those of you who have specific questions
can either post them to the list or address them to me personally at
rranous(--nospam--at) and I will answer immediately.  Please identify your
response as northern California or southern California.  Depending on
the results of this request, we may have to break California into more
than two regions.  This will also help us to determine how many regions
we will consider on the national basis.  If this request is successful,
sometime this spring we will again request your assistance on a national
basis, state specific.

Again, thank you all in advance for your assistance.  This will be very
helpful to the work we are doing.  As a side note, HAZSUS is a software
that is in the public domain!  If you are interested in the software, I
would suggest that you contact FEMA for more information.  HAZSUS is
being used to define "project impact" communities.  Information on
project impact can be found on the FEMA web page at

Rick Ranous, SE
EQE International