Contact

Bret M. Webb, Ph.D., P.E., D.CE
Professor
University of South Alabama
150 Jaguar Drive, SH3142
Mobile, AL 36688 USA
Phone: (251) 460-6174
Fax: (251) 461-1400
Email: bwebb@southalabama.edu

Research Positions

Currently seeking an MSCE student to perform research on groundwater impacts to coastal lagoons. A research assistantship is available. Contact me for more details.

Current Research Assistants

SE Students
Garland Pennison

 

MSCE Students
Patrick Hautau
Marshall Hayden
Jackie Wittmann

 

Undergraduate Students
Derek Kelly

Former Students

MSCE Students
Kate Haynes (2018)
Justin Lowlavar (2017)
Bryan Groza (2016)
Kari Servold (2015)
Chris Marr (2013)
Richard Allen (2013)
Miyuki Matthews (2012)

 

Post Docs
Jon Risinger
Jungwoo Lee

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FHWA GI Pilot title slide... click for animation

We are wrapping up a one-year collaborative project between USA, the Mississippi Department of Transportation (MDOT), and the US Department of Transportation Federal Highway Administration (USDOT FHWA).  This was one of five pilot projects funded by USDOT FHWA to evaluate the use of green infrastructure for improving the resilience of coastal transportation systems. The pilot projects are an initial step in a more comprehensive effort by USDOT FHWA to develop an implementation guide for nature-based solutions that improve resilience. More information about that project is found at the following link {click here}.

 

Our pilot project with MDOT was focused on improving the resilience of a coastal bridge in Mississippi to hurricane hazards and future sea level rise. More specifically, our green infrastructure approach was designed to address the vulnerability of bridge approaches and low-elevation bridge spans. The causes of damage to the bridge during Katrina were determined through the use of hydrodynamic models. A hindcast simulation of Katrina was performed using the coupled ADCIRC+SWAN models. Those results were extracted and used to force a high-resolution, two-dimensional simulation using the XBeach model. An animation of some of those results is provided below.

 

To that end, a pair of vegetated berms were designed in order to mitigate storm damage now and in the future during extreme events.

 

An overview of the entire pilot project is available in a recorded webinar at the following link {click here for webinar}. Ours is the second presentation in the webinar recording (at about the 25-minute mark). Webinar recordings for all five pilot projects, as well as other presentations in an ongoing USDOT FHWA resilience series, can be found at the following link {click here for all webinars}. A brief animation of our presentation slides is available by clicking on the title slide image in this post.

 

Katrina Hindcast using XBeach, forced with ADCIRC+SWAN output…

XBeach animation

Hindcast of Katrina using XBeach: Terrain elevation contour colors correspond to the lower blue-green-brown-white color scale. Selected bathymetric contours are shown as dashed white lines on the surface. The animated water surface is contoured by significant wave height using the blue-white-red scale. Vectors represent the depth-averaged flow magnitude and direction, but only at every 1/10th grid cell for clarity.

 

Check out the new issue of Shore & Beach (the Journal of the American Shore & Beach Preservation Association) for a very interesting article by Scott Douglass, myself, Caren Dixon, and Beau Buhring focused on proactive coastal engineering strategies for combatting oil spills on sandy beaches. Click on the image at right for a link to the abstract hosted by the ASBPA web site, or just click {here}. This volume of Shore & Beach has some other very good articles centered around the theme of “learning from disasters.” Here is an (almost) complete citation for our latest article:

  • Douglass, S. L.,Webb, B. M., Dixon, C. R., Buhring, T. 2011. Beach profile and island cross-section manipulations in response to an offshore oil spill. Journal of the American Shore & Beach Preservation Association, 79(4).

Thanks Delta and Google Chrome for allowing me to procrastinate at 35,000 feet. Free Wi-Fi on the plane is great. Now time to get some work done before I land.

It’s been more than one month since our last field experiment at Katrina Cut, and a lot has happened since that time. Thompson Engineering has made significant progress on the breach closure in the past few weeks {link to a flickr gallery}; BP has installed a fitted cap on the MC 252 well head that appears to be staunching the flow for now; and cleanup crews are pulling up their tent stakes and heading away from the beaches in Alabama (for now).  Now that we are mostly done dealing with the visible stuff, only time (and lots of research) will tell how much the unseen will effect the environment.

In the meantime, here is a three-dimensional rendering of interpolated bathymetry at Katrina Cut as of June 24, 2010.  Of course, things will have changed substantially by the time construction of the breach closure is complete.  A follow-up trip for monitoring is planned for early fall.