Version 5 of HEC-RAS allows the use of rating curves for inline structures (and lateral structures). Rating curves can be added through the Outlet RC feature in the inline structure editor. Inline structure rating curves can be useful for evaluating the impacts of structures, such as labyrinth dams, where it may be difficult to correctly […]
*Update: Version 5.0.2 now does flow transects in RAS Mapper with profile lines. No longer necessary to use a 2D Area Connection to do this. A very common output request in 2D modeling is for flow over (through) a transect line. HEC-RAS 5.0 does not have a specific tool for extracting flow data along a […]
Here’s a nice feature in HEC-RAS input tables that will save you a little bit of time. Let’s say you want to highlight an entire column of data. Maybe you want to delete all of the values in that column or paste in a block of data. Or perhaps you want to highlight all of […]
Another simple, yet very convenient tool not found discussed in the manuals is the ability to zoom in on one of the axes of a graphical plot. This is especially useful when trying to determine if you’ve captured the true peak discharge in a steeply rising hydrograph. Take the following example: an unsteady flow dam […]
I’ve mentioned many times on this blog and in class about the importance of having your initial conditions flow match your first time step flow, when running an unsteady flow model. As with any “rule” in RAS modeling, there are exceptions to this, but generally speaking, if your first timestep flow is “X”, then your […]
I was recently asked my opinion on a good way to model the following dam breach event: “I …recently completed three consulting projects where I simulated the breach of three proposed coal slurry impoundments. The permitting agency required a RAS model of an “instantaneous” hypothetical breach (over full depth, almost 80 ft for one of […]