Free Webinar on Dam Breach Modeling

Webinar: Dam Breach Modelling

Colleagues-

I'm honored to join Krey Price and Bill Syme in presenting a brief webinar on dam breach modeling hosted by ICEWaRM and the Australian Water School.  Half hour presentation followed by discussion and a Q&A session.  Please join if you can.





https://www.icewarm.com.au/australian-water-school/short-courses/course/dambreak-modelling/

A vigorous discussion with a group of highly regarded dam breach modellers

Approaches to dam breach modelling vary greatly when estimating the discharge through the breach and potential downstream inundation impacts.

This webinar will address 3 key issues:
1) upstream of the dam (reservoir) Krey Price 5 min
2) the dam itself (breach parameters) Chris Goodell 10-12 min
3) downstream of the dam (flood wave routing) Bill Syme 10-12 min

The different approaches to generating the breach hydrograph, the numerical modelling of downstream flood inundation, benchmarking of solution schemes, and uncertainties associated with the modelling will be presented and explored.

Click the link below for more information and to register.

https://www.icewarm.com.au/australian-water-school/short-courses/course/dambreak-modelling/

HEC-RAS 5.0 versus TUFLOW versus MIKE21 – HEC’s official response

In case you haven’t seen it, there has been a very popular LinkedIn discussion on the Hydraulic/Hydrologic Modeler’s Forum debating the advantages, disadvantages, and merits of HEC-RAS 5.0, TUFLOW, and DHI’s MIKE21.  There was a lot of great information (and some misinformation) and insight provided in that thread.  It is well worth the read.  Some of the misinformation was directed at the beta version of HEC-RAS Version 5.0.  Enough that HEC decided to publish a response to clear up any confusion.  

At play is a result of HEC-RAS’s 2D solution scheme using the full shallow water equation where for highly dynamic events where flows severely contract, using too small of a time step could lead to a divergence from the true solution, rather than a convergence.  This is not an issue when a computation interval is selected within the guidance presented by HEC in their user’s manual.  While HEC disagrees that this is a necessarily a “problem” with its software, as some on the discussion claim,  HEC has elected to make this a non-issue by “improving the portion of the full shallow water equation formulation, such that user’s will be able to use very small time steps without the results changing significantly.”   I’ve included HEC’s response, written by Gary W. Brunner, to the LinkedIn discussion below, but I highly recommend you read the LinkedIn discussion first by clicking here: 

I’m posting this not just to allow HEC to reach a larger audience with their rebuttal, but also because there is a LOT of great information in this document about how HEC-RAS 2D works and how we, as HEC-RAS 2D modelers should use it.  Please enjoy!  A downloadable pdf is available here.

The following text is copyrighted by the Hydrologic Engineering Center and Gary W. Brunner: