Hydro File Error

Any questions regarding the practice version are asked and answered here.
Post Reply
Bahman Esfandiar
Posts: 3
Joined: Tue Jan 22, 2019 2:31 pm

Hydro File Error

Post by Bahman Esfandiar »

Hi All,
I am getting the following error when trying to do drainage design with rational method, any suggestion?
ERROR: Hydro file Global data:Frequency must be ARI for rational method.
I am using 12d V14.0C2d and the IFD values are form BOM.
Matthew Monk
Posts: 3175
Joined: Fri Oct 21, 2005 2:46 pm

Re: Hydro File Error

Post by Matthew Monk »

As I understand it, the IFD tables provided by the BoM are listed per AEP (Annual Exceedance Probability). 12d Model requires this to be expressed in ARI (Average Recurrence Interval) instead. See also this: http://www.bom.gov.au/water/designRainfalls/#sec1q5

Basically, you need to edit your IFD row of AEPs and convert them to their ARI values.
12dwiki.com.au - Tips, tricks and tutorials for users of 12d Model

12d Synergy Support Portal and Knowledge Base
Bahman Esfandiar
Posts: 3
Joined: Tue Jan 22, 2019 2:31 pm

Re: Hydro File Error

Post by Bahman Esfandiar »

Thanks Matt, However, I should be able to use both AEP and ARI with Rational method. I have used it before and in 12d YouTube channel there is a video (https://youtu.be/hGa4ZvvTqqQ?t=482) where the instructor clearly uses the BOM IFD data in AEP format. I am just wondering if anyone else encountered this error or am I missing something obvious.

Cheers,
Matthew Monk
Posts: 3175
Joined: Fri Oct 21, 2005 2:46 pm

Re: Hydro File Error

Post by Matthew Monk »

No idea. I was just going off what the error message was saying.
12dwiki.com.au - Tips, tricks and tutorials for users of 12d Model

12d Synergy Support Portal and Knowledge Base
Brady Williams
Posts: 33
Joined: Tue Jan 31, 2017 4:57 pm

Re: Hydro File Error

Post by Brady Williams »

Did you download the "all design rainfalls CSV" from BOM?

In V14, only the first 10 columns in the .12dhydro IFD table can be read. If you downloaded the all design rainfalls file, chances are you will have more than 10 columns so if you are trying to run a 1% AEP or 100-year ARI, you will get an error (mine wasn't identical to yours but similar).

Try removing some of the columns you don't need and see if that works :D
Owen Thornton
Posts: 5607
Joined: Tue Oct 04, 2005 12:50 pm
Location: Brisbane
Contact:

Re: Hydro File Error

Post by Owen Thornton »

Upgrade to the latest v14. It supports ARI or AEP for use with Rational. Not sure exactly which version first included this enhancement. Feels like more than two years ago.
Bahman Esfandiar
Posts: 3
Joined: Tue Jan 22, 2019 2:31 pm

Re: Hydro File Error

Post by Bahman Esfandiar »

Updated to V.14.0C2h and problem solved.
Post Reply