Open section roadway drainage

Hi,

Is there a way to model roadside ditches conveying overflow discharges to inlets (grate inlets) downstream  that are a part of a storm drain system of an open section road without curbs. I could only find information about Curb/gutter. there are no examples of how to model an grate inlet in a ditch for an open section roadway.

Thanks!

  • Works the same as a curb and gutter roadway, except the inlets get placed in the ditch instead of on the roadway.  The feature definitions for the ditch inlets will be different of course. For the overflow (IE bypass flow) can get a little tricky.  I recommend you explore the following two options to see which works best for you.

    • to account for the bypass (overflow) to the next ditch inlet just define a hydraulic gutter just as if you were designing on a curb and gutter roadway. This will account for the bypassed flow and allow for a proper spread calculation on the ditch inlets.
    • The tricky part is that we usually want to define the ditch segments as conduits so that we can see if the ditch is capable of carrying the water.  The problem is when treating ditches as conduits it will not compute spread.

    So, we usually end up computing it both ways once where we consider the spread and bypass and once where we treat ditches as conduits.  Scenarios and active topology are your friends here.  

    Robert Garrett
    Senior Consultant

    www.envisioncad.com