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Recent content by sknight701

  1. sknight701

    HEC-RAS: spillway approach height for overflow gate

    I see your point. The program should take the gate opening from the flow data, a mean ground surface elevation from the geometric data, and calculate the approach height for the profile. I must admit, you have me stumped. I'll try looking into this a little more. If you find out anything...
  2. sknight701

    HEC-RAS: spillway approach height for overflow gate

    Sounds like you might want to try inputting performance curves for your gage. Select "user defined gate curves" from the gate type selector, and input the performance data. See pages 6-71 thru 6-74 of the users manual. Hope this helps.
  3. sknight701

    Two TR-55 questions

    Sounds like you are making things way too complicated for such a small watershed. Why not create just one large drainage area for your point of interest, use a weighted average RCN, calculate the time of concentration from the farthest point, and get your flow hydrograph from TR-55? To...
  4. sknight701

    HEC-RAS Encroachment Analysis Elevations Need Help

    I noticed that ineffective areas were not part of your model, and was about to inquire when I read your latest posting. Oh yes, ineffective areas are almost always necessary and there are some rules as to where to place them. First, set up your bounding cross sections at the structure using...
  5. sknight701

    stormwater energy dissipator for steep slope

    You might want to take a look at the Federal Highway Administration HEC-14 document.
  6. sknight701

    HEC-RAS Encroachment Analysis Elevations Need Help

    I checked the report over the weekend, but could not find anything else. Something seems to be blocking your culverts. Hope this helped.
  7. sknight701

    HEC-RAS Encroachment Analysis Elevations Need Help

    I concur with amb2002. Your 100-year profile shows flow thru both culverts, but your floodway profiles show zero flow thru both culverts. That is probably your problem. Be sure you are not blocking the culvert with your encroachment data (essentially burying the culverts). There may also...
  8. sknight701

    HEC-RAS Encroachment Analysis Elevations Need Help

    I am going to look at these during lunch today, and possibly take home printouts over the weekend. I'll get back to you ASAP
  9. sknight701

    Storm sewer hydraulic modeling

    Many Thanks.
  10. sknight701

    HEC-RAS Encroachment Analysis Elevations Need Help

    I just opened those files you sent, but they do not provide the information that I need. I suggest that you do the following. Open up the plan file in RAS. Go to File/Generate Report and generate the report. Print out the report, scan it as a .pdf file, and upload the .pdf to this website...
  11. sknight701

    HEC-RAS Encroachment Analysis Elevations Need Help

    If your cross sections, channel, etc., are not georeferenced, then the perspective plot can really get weird. This in no way affects the quality of the model itself, so don't worry about it. Just don't use the perspective plot in any reports. I'll take a look at the files and get back to you...
  12. sknight701

    HEC-RAS Encroachment Analysis Elevations Need Help

    There are several reasons that your model may not be working, and it would be useful for you to post your entire model so we can see it. But I will try a few guesses to start: Is all culvert geometry entered properly? Do the results yield vertical "walls" at the outer boundaries of the...
  13. sknight701

    Storm sewer hydraulic modeling

    Does anyone out there know of a good stand alone program that will calculate the hydraulic grade line of a storm sewer system with multiple inlets, manholes, pipes, etc.? I know that the old Hydraflow Storm Sewer program did this, but it is now an extension for AutoCAD, which my company does...
  14. sknight701

    Encroachment in Hec_Ras

    I would have expected the water surface to drop due to increasing the bridge opening. Did you analyze your ineffective flow stations and elevations properly to account for the change in the bridge? You might want to post your site plan with cross sections and maybe the RAS report too.
  15. sknight701

    Snow Melt Design

    The worst case scenario for you would be a rain on snow event, which includes the rainfall and the snowmelt caused by the rainfall. Assuming you used the the SCS method to calculate your runoff, you could change the antecedent runoff condition to type III (fully saturated antecedent conditions)...

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