Discussion Central

1.  Hurricane Harvey - How do you handle 4 inch ran an hour etc. ?

Posted 08-25-2017 13:05
Personally me as a AIChE chemical engineer flooding / marine environment - offshore oil - ship etc. / hurricanes include Sandy - Katharina - Ike etc. back grounded wish to stay out of ones running to deal with such. Things that I learned were
1. Computer in basements low in building can be big losses.
2. Salt water into Insulation is a big cost to get returned to service.
3. WD40 put onto dewatered machinery as fast as possible controls loss.
Your views appreciated.


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Len Andersen - www.gasturbineandersen.com
Water Swirled Into Gas Turbine Technology
Gas Turbine Engineer AWS CWI
ASME Paper Presenter len@lenandersen.com HP Securemail
914-536-7101
800-428-4801
Caller Box at Large Post Office POB 1529 NYC 10116 +1299/yr
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2.  RE: Hurricane Harvey - How do you handle 4 inch ran an hour etc. ?

Posted 16 days ago
  |   view attached
​Please share learning experiences with our USA hurricanes. From TV the young people shovels in hand clearing off ramp on I-45 said a lot !

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Len Andersen - www.gasturbineandersen.com
Water Swirled Into Gas Turbine Technology
Gas Turbine Engineer AWS CWI
ASME Paper Presenter len@lenandersen.com HP Securemail
914-536-7101
800-428-4801
Caller Box at Large Post Office POB 1529 NYC 10116 +1299/yr
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3.  RE: Hurricane Harvey - How do you handle 4 inch ran an hour etc. ?

Posted 13 days ago
Design and build drainage systems and impoundment areas to some "bigger" storm than the building code specifies.  If the code specifies a 25 year storm, build it for a 100 year or a 500 year storm.  Ignorance on how often a 100 year or 500 year flood  can occur abounds.

Same goes for roof coverings and flashings on flat roofs of large industrial/commercial buildings.  Fasten them for what can actually happen (e.g. Cat 4 Hurricane) instead of the minimums in the building codes.

Our industry can do the above and still be profitable.  Municipalities and other levels of government that pay to build stuff like highways will never do it.  Thus the kids with shovels on the Interstate ramp.

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John Sharland PE,FSFPE
Bridgewater MA
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4.  RE: Hurricane Harvey - How do you handle 4 inch ran an hour etc. ?

Posted 12 days ago
Just to reinforce that many people do not know how often a 100 year flood can occur.
consider this: the probability of a 100-year flood not occurring for 100 years is about 1/3.

Probability that a 100year flood occurs this year = 1/100
Probability that a 100year flood does not occur this year = 1 - 1/100 = 99/100
Probability that a 100year flood does not occur for 100 consecutive years = (99/100)^100 = 36.6%

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Thomas Wilson
Houston TX
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5.  RE: Hurricane Harvey - How do you handle 4 inch ran an hour etc. ?

Posted 11 days ago
As Thomas Wilson pointed out, the "probability that a 100year flood does not occur for 100 consecutive years = (99/100)^100 = 36.6%" However this is like many of our early engineering courses where we postulated frictionless environments and perfectly level planes. However, out in the real world we have things like a design figure of 13 inches in 24 hours as a 100-year storm in Houston, but 13 inches of rain has occurred more than eight times in the last 27 years."  So what is the probability of the stated value for a 100-year storm in Houston being correct when it, in fact, happens about every 3 or 4 years?