Blue Roof Model in HydroCAD

[Sebast73]

Any HydroCAD aficiando's out there, I am looking to model a "Blue Roof" for storm water detention using HydroCAD
Using the custom stage storage data modeled as a pond, how may I simulate a slow release on the volume stored ?
I am pretty efficient using underground storage techniques, but the custom detention pond is new to me. Any input will be greatly appreciated.

Thanks in advance for your input.

Sebast1973

 

[psmart]

You could use an exfiltration outlet... It all depends on what you're using for outlet control(s).

Peter Smart
HydroCAD Software

http://www.hydrocad.net

 

[Sebast73]

Thanks psmart,
Do you have any suggestions? This information , I am assuming will be obtained by the outlet control mfg.?
The project is located in New England, therefore ice and snow is also an issue. Would you kindly provide an example using the exfiltration outlet?
Thanks for your time.

 

[psmart]

Can you provide details on the design? You said you're already setup customs storage data. What are you using for outlets? If you already have a HydroCAD file it would help to post the file. A sketch would also be helpful. Need details in order to provide meaningful advice.

Peter Smart
HydroCAD Software

http://www.hydrocad.net

 

[Sebast73]

psmart,
Yes, I most certainly will post the HydroCAD file and any pertinent details once I have re-designed my model. I created a quick original model previously, using the pre-defined outlets HydroCAD has built in to the program, but now I have more info. therefore need to update my drainage areas, etc.
Thanks again for your time and I look forward to your assistance and solution.

Sebast73

 

[Sebast73]

psmart and/or other HydroCAD aficionados,
Please see attached PDF files and HydroCAD files. Input welcome, please. I need the Blue Roof to attenuate the flow abit, not increase the runoff ??
Looking forward to your feedback. Going to be up allnight writing this SWPPP. Thanks for your assistance. I tryed to upload the files individually, but then It seemed as if I was overwriting, therefore I created a .zip file which entails the following, DA map EX, and PRO, HydroCAD files, Pre and Post.

Sebast73

 

[psmart]

I'm having difficulty understanding the situation you're trying to model.

1) You have 16+ acres in the "DA of concern" that is routed to the "blue roof" modeled by pond 1P. So the pond storage is on the "roof" of an underground mausoleum? (It must be lower than the entire 16+ acres in order for the water to drain to that point.)

2) What exactly do you mean by "blue roof"? A sketch would be helpful. Your defined storage is only 3 inches deep. I'm guessing this is storage on the flat roof? What is the exfiltration mechanism? Is this media (soil) with an underdrain? How does this relate to the vortex valve?

3) The storage of the "blue roof" is at 15 feet elevation, but the pond is routed to a "dry swale" with an inlet invert elevation of 280 feet. How does the water get up 265 feet from the pond to the swale?

4) Finally, there are numerous warning messages that must be resolved in order to obtain meaningful results. Several of these may be related to issue 3. Please click each warning for details and recommended solutions.



Peter Smart
HydroCAD Software

http://www.hydrocad.net

 

[Sebast73]

psmart,
Thanks for your feedback, this will help in my learning the software. To explain a bit more in detail, the blue roof is simply to catch the rainfall from the newly created impervious area, that is it, to strictly attenuate this 4200 sf volume for a time span to allow for Water Quality , the Blue roof system is an approve BMP for New York State. The outlet controls are to be determined. Im assuming depends on Mfg.
So once the roof water drains down into the rain leaders, it will then flow to the swale, or It will be directed to the swale. Does that make it a bit more clear ?

My main concern is to shown an decrease in runoff and volume after the Blue roof, or Pond, which I was unable to do ?

Work in progress, again thanks for the input and feedback, I will attempt to correct the error messages.

Sebast73

 

[psmart]

At present you are sending the entire runoff from 16+ acres to the pond, not just 4200 sf. Hence the storage-exceeded warning. If you only want 4200 sf to go to the pond you should setup a separate subcat for that area.

You also need to fix the elevation discrepancy between the roof and the swale that I previously mentioned.

After making the changes be sure to review any remaining warning messages, which will identify most modeling issues.


Peter Smart
HydroCAD Software

http://www.hydrocad.net

 

[Sebast73]

OK,
That makes sense, yes logically there is no way or need to put the entire acreage on the "Blue Roof", this should start to work out better. Any suggestions on an additional green infrastructure method of storm water treatment, such as a storm water planter or a rain garden ? How do these type of treatment methods get modelled using HydroCAD ? ANy examples you may have or insight will help and like always is extremely appreciated. I only wish there was a way to "pay back" or pay forward, please keep me in mind if you ever need insight or assistance in Geo-Technical matters or construction inspections. Thank you and look forward to an ongoing professional relationship.
Do you have experience in using EPA's SWMM, or Hec Ras ?

Sebast73

 

[psmart]

For details on modeling rain gardens in HydroCAD see

http://www.hydrocad.net/raingarden.htm

Peter Smart
HydroCAD Software

http://www.hydrocad.net