Environment, Coasts, Oceans, & Infrastructure

Hi Everyone, 

I'd like to share some of the flood hazard mapping products our group at UC, Irvine has produced using 2D hydraulic models: 

bit.ly/floodrise_TRV                     -> Tijuana River Valley Flood hazard maps
bit.ly/floodrise_oroville                 -> Oroville Dam emergency spillway maps

All of these maps were produced using our research group's 2D modeling software, but HEC-RAS 5.0 can provide similar data output. The maps that require velocity information (force and shear stress maps) would be difficult to produce using traditional 1D mapping.  We have found that shear and force maps are particularly useful for natural resource managers and emergency responders.

For those interested, I am giving a presentation at the EWRI Congress in Sacramento regarding the reception and utility of these maps from "end users' " perspectives, and would be more than happy to discuss my presentation if anyone has questions.

Cheers, 
Adam


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Adam Luke A.M.ASCE
Newport Beach CA
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Hi Adam

Thanks for sharing the maps. Great work!.  Is there a reference for the flow velocity breakdown values used in the map ?

Thanks
Rishab

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Rishab Mahajan Aff.M.ASCE
Geosyntec Consultants
Oak Brook IL
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Hi Adam, 

Thanks for this very interesting contribution ! A key point is the selection of physically based vulnerability curves for different targets (people, houses, cars...), and in this direction Rishab question is important. Recently we published a practical contribution that possibly can be of interest for its easy applicability 

• Milanesi, L., Pilotti, M., Ranzi, R. (2015), A conceptual model of people's vulnerability to flood, Water Resources Research, 51,  doi:10.1002/2014WR016172.

The code includes a software to convert (U,Y) maps to people stability hazard. We hope it can be useful to the community and maybe stimulate a discussion on this rather overlooked issue .

Marco

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Marco Pilotti P.E., M.ASCE
Prof.
Università Degli Studi Di Brescia
Brescia
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Original Message:
Sent: 05-24-2017 09:50
From: Rishab Mahajan
Subject: flood hazard maps based on 2D modeling

Hi Adam

Thanks for sharing the maps. Great work!.  Is there a reference for the flow velocity breakdown values used in the map ?

Thanks
Rishab

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Rishab Mahajan Aff.M.ASCE
Geosyntec Consultants
Oak Brook IL
------------------------------

Hi Marco, 

Thanks for the reference!  We agree that stability thresholds are very important for emergency responders and other aspects of flood risk management.  From our interactions with first responders in the Tijuana River Valley area, we found that they are really interested in the location of hazardous areas within the floodplain.  In our upcoming paper, we argue that this kind of data should be produced along with the traditional flood extent maps so that aspects of flood risk management other than flood insurance can be supported with floodplain mapping.  

In my opinion, the "low hanging fruit" for reducing losses from floods is to better support emergency management.  It can be very difficult to restrict or remove developments from the floodplain, so reducing losses when floods do happen becomes very important.  

-Adam 

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Adam Luke
MSc, Civil Engineering
PhD Candidate, Hydrology and Hydraulics
aluke1@...
------------------------------

Original Message:
Sent: 05-25-2017 06:58
From: Marco Pilotti
Subject: flood hazard maps based on 2D modeling

Hi Adam, 

Thanks for this very interesting contribution ! A key point is the selection of physically based vulnerability curves for different targets (people, houses, cars...), and in this direction Rishab question is important. Recently we published a practical contribution that possibly can be of interest for its easy applicability 

• Milanesi, L., Pilotti, M., Ranzi, R. (2015), A conceptual model of people's vulnerability to flood, Water Resources Research, 51,  doi:10.1002/2014WR016172.

The code includes a software to convert (U,Y) maps to people stability hazard. We hope it can be useful to the community and maybe stimulate a discussion on this rather overlooked issue .

Marco

------------------------------
Marco Pilotti P.E., M.ASCE
Prof.
Università Degli Studi Di Brescia
Brescia
------------------------------

Hi Risab, 

Thanks for your comment! For the Tijuana River Valley maps, the v*h thresholds were defined from the following sources: 

Stability of people from Xia et al. (2014).  The threshold of 4.3 ft^2/s refers to when children or small people become unstable. 

Cars displaced from Xia et al. (2011).  The threshold of 8.1 ft^2/s is when mini-coopers or small cars begin sliding according to their study. 

Structural home damage from Gallegos et al. (2012), the KRBQ metric.  The threshold of 16.1 ft^2/s corresponds to a moderate damage state defined in Gallegos et al. (2012). You can follow the references therein for the origin of the metric. 

Homes washed away from Gallegos et al. (2012), the BLK2 metric. The threshold of 27 ft^2/s corresponds to a severe damage state or "washout" defined in Gallegos et al. (2012). 

We are writing up a paper right now with all of the mapping methods and scale references.  In this study, we are also reporting the reception of these maps from a variety of professionals who could benefit from flood hazard data.  The online maps resulted from our discussions with end-users in the Tijuana River Valley area. 

References: 

Gallegos, H. A., Schubert, J. E., and Sanders, B. F.: Structural damage prediction in a high-velocity urban dam-break flood: field-scale
5 assessment of predictive skill, Journal of Engineering Mechanics, 38, 1249–1262, 2012.

Xia, J., Teo, F. Y., Lin, B., and Falconer, R. A.: Formula of incipient velocity for flooded vehicles, Natural Hazards, 58, 1–14, 2011.

Xia, J., Falconer, R. A., Wang, Y., and Xiao, X.: New criterion for the stability of a human body in floodwaters, Journal of Hydraulic
Research, 52, 93–104, 2014.

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Adam Luke
MSc, Civil Engineering
PhD Candidate, Hydrology and Hydraulics
aluke1@...
------------------------------

Original Message:
Sent: 05-24-2017 09:50
From: Rishab Mahajan
Subject: flood hazard maps based on 2D modeling

Hi Adam

Thanks for sharing the maps. Great work!.  Is there a reference for the flow velocity breakdown values used in the map ?

Thanks
Rishab

------------------------------
Rishab Mahajan Aff.M.ASCE
Geosyntec Consultants
Oak Brook IL
------------------------------

Hi Adam - Nice maps!
I would be interested to know what routine you are using to designate the different "intensity" bins.  It appears you are using similar approach to the NRCS Hazard Classification and if so it would be good to reference your approach on the map.

Secondly, as a color blind consumer of modeling information, I would point out that the color ramping used for the different hazard classifications could be improved.  Approximately 10% of US males are color blind and they too want to be able to see your good work.  A neat way to visualize how your color choices appear to color blind people like me is to use the tool on the website http://colororacle.org/ .  Another tool you could use is http://colorbrewer2.org/ that suggests color blind friendly schemes for use in graphics.

Keep up the good work!
Mark Ruebel

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Mark Ruebel P.E., M.ASCE
CAPITAL TEAM SUPERVISOR
KING COUNTY WLRD
SEATTLE WA
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Hi Mark, 

These are excellent points.  I provided the references for the intensity thresholds in a response to Rishab's post, but you are right I should also put them on the website. 

Thank you for the links to the color blind visualization tool.  I have not seen this before.  I was advised to not use red and green colors in the same scales, but that was about the extent of color blindness consideration.  Those links will be very helpful for improving the color scales! 

-Adam 



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Adam Luke
MSc, Civil Engineering
PhD Candidate, Hydrology and Hydraulics
aluke1@...
------------------------------

Original Message:
Sent: 05-24-2017 13:11
From: Mark Ruebel
Subject: flood hazard maps based on 2D modeling

Hi Adam - Nice maps!
I would be interested to know what routine you are using to designate the different "intensity" bins.  It appears you are using similar approach to the NRCS Hazard Classification and if so it would be good to reference your approach on the map.

Secondly, as a color blind consumer of modeling information, I would point out that the color ramping used for the different hazard classifications could be improved.  Approximately 10% of US males are color blind and they too want to be able to see your good work.  A neat way to visualize how your color choices appear to color blind people like me is to use the tool on the website http://colororacle.org/ .  Another tool you could use is http://colorbrewer2.org/ that suggests color blind friendly schemes for use in graphics.

Keep up the good work!
Mark Ruebel

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Mark Ruebel P.E., M.ASCE
CAPITAL TEAM SUPERVISOR
KING COUNTY WLRD
SEATTLE WA
------------------------------

My group at UC Davis recently published a new practical analytical framework for flood hazard mapping using 2D model outputs to ascertain the meter-resolution hazard proximity and reaction time of a victim in flood waters. Although we developed it using data from whitewater rivers, the algorithms work just fine in any 2D inundation scenario.  The citation is given below and if anyone wants a copy of the reprint and the full hazard classification maps we made, just send me an email (gpast@...) and I'll be glad to reply with that for you.

Strom, M. A., Pasternack, G. B., Burman, S. G., Dahlke, H. E., Sandoval-Solis, S. 2017. Hydraulic hazard exposure of humans swept away by a flow in a mountain river. Natural Hazards. doi:10.1007/s11069-017-2875-6.

Regards,

-Greg Pasternack

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Gregory Pasternack Ph.D., A.M.ASCE
Professor
University of California
Davis CA
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Adam,

The maps look great! I echo the comment to give some thought to the color scale considering the frequency of color blindness. I personally have some trouble with your color scheme.

I particularly appreciate the ankle high, waist high, etc. qualitative description of flood depths to aid the lay person. To this aim, I noticed that you referenced the coastal water levels to MLLW. The MLLW datum is great for scientist and engineers since local surveys are recorded (or should be) at Low Tide. However, when I work with the public or decision-makers in understanding coastal hazards, I find it more informative to refer coastal flood elevations to the MHHW. It is easier to understand, colloquially, as the 'tide as a 1-percent chance of getting X' higher than the daily high tide in any given year.'

Cheers, 

Joe


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Joseph Faries P.E., M.CE, CFM
Coastal Engineer
Stantec Consulting, Ltd.
Laurel MD
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Hi Joe, 

Thanks for the comments.  I will definitely reconsider the color scales.  Also, the black outline of the river channel underneath the transparent layers could  be a source of confusion.  It appears that there is a darker shade than included in the legend as of now. 

I agree that the MHHW datum is more intuitive because, as you point out, it refers to feet above average high tide.  I went with MLLW because websites like Surfline report tide levels relative to MLLW.  Actually, they post a tide height without referencing a datum haha (but it appears to be MLLW). Hopefully, users that are interested in the boundary conditions that produced the map will be able to convert between datums. 

-Adam 

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Adam Luke
MSc, Civil Engineering
PhD Candidate, Hydrology and Hydraulics
aluke1@...
------------------------------

Original Message:
Sent: 05-25-2017 09:17
From: Joseph Faries
Subject: flood hazard maps based on 2D modeling

Adam,

The maps look great! I echo the comment to give some thought to the color scale considering the frequency of color blindness. I personally have some trouble with your color scheme.

I particularly appreciate the ankle high, waist high, etc. qualitative description of flood depths to aid the lay person. To this aim, I noticed that you referenced the coastal water levels to MLLW. The MLLW datum is great for scientist and engineers since local surveys are recorded (or should be) at Low Tide. However, when I work with the public or decision-makers in understanding coastal hazards, I find it more informative to refer coastal flood elevations to the MHHW. It is easier to understand, colloquially, as the 'tide as a 1-percent chance of getting X' higher than the daily high tide in any given year.'

Cheers, 

Joe


------------------------------
Joseph Faries P.E., M.CE, CFM
Coastal Engineer
Stantec Consulting, Ltd.
Laurel MD
------------------------------

Dear All,
I'd like to suggest another publication/study on flood criteria based on velocity times water depth listed below as well as its link for download
Hiroshi Takagi1 , Takahito Mikami2 , Daisuke Fujii1 , Miguel Esteban3 , and Shota Kurobe. 2016. Mangrove forest against dyke-break-induced tsunami on rapidly subsiding coasts
http://www.nat-hazards-earth-syst-sci.net/16/1629/2016/nhess-16-1629-2016.pdf


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Dov Rosen P.E., M.ASCE
Sergiu Dov Rosen Sea Shore Rosen Engineering Consultants
Haifa, Israel
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Original Message:
Sent: 05-25-2017 09:17
From: Joseph Faries
Subject: flood hazard maps based on 2D modeling

Adam,

The maps look great! I echo the comment to give some thought to the color scale considering the frequency of color blindness. I personally have some trouble with your color scheme.

I particularly appreciate the ankle high, waist high, etc. qualitative description of flood depths to aid the lay person. To this aim, I noticed that you referenced the coastal water levels to MLLW. The MLLW datum is great for scientist and engineers since local surveys are recorded (or should be) at Low Tide. However, when I work with the public or decision-makers in understanding coastal hazards, I find it more informative to refer coastal flood elevations to the MHHW. It is easier to understand, colloquially, as the 'tide as a 1-percent chance of getting X' higher than the daily high tide in any given year.'

Cheers, 

Joe


------------------------------
Joseph Faries P.E., M.CE, CFM
Coastal Engineer
Stantec Consulting, Ltd.
Laurel MD
------------------------------

Adam,

Very nice work.  I see you have given references for the stability of people, cars, etc.   I did not see a reference for categorization for your erosion potential layer.   Forgive me if I missed it.

Bob Holmes

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Robert Holmes Ph.D., P.E., D.WRE, F.EWRI, F.ASCE
National Flood Hazard Coordinator
US Geological Survey

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Hey! Adam, I hope You are doing well.

My question is a bit off topic, I am final year Civil engineering student and My fyp Project is Flood Frequency Analysis Using Deep learning Models. I have noticed that there hasn't been appreciable work done in this domain despite of its immense potential. As an expert I would like to know your comments.

Thanks 

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Mohsin Ahmad S.M.ASCE
Student
Pabbi
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