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Patrick_Tunnah
September 18, 2015, 01:23 AM
Hi,

I'm a bit confused with how the DWF patterns work in InfoSWMM/ H2OMap SWMM. I had a look at an earlier forum post and it is still unclear.

I have set up my DWF with the VALUE as the #of EP, PATTERN1 as dry weather flow conversion (L/EP/day), and PATTERN2 as a non-residential or residential identifier (multiply by 1). PATTERN1 is an hourly pattern and PATTERN2 is a daily pattern. I would expect the DWF calc to go as VALUE * PATTERN1 * PATTERN2. However my model seems to calculate VALUE * PATTERN2 and ignores the PATTERN1...

I set up a test model with single manhole->pipe->outfall. Then put 1 L/s DWF with a factor of 2 in PATTERN1 and a factor of 10 in PATTERN2. It didn't seem to matter what type (monthly, daily, hourly, weekend) the patterns were, as it would only multiply by one of the patterns.

I just want to add a second pattern multiplying by 1 to my DWF sets, without creating a set of patterns for residential and a set of patterns for non-residential. Does anyone have any suggestions? Or can point out what I've missed?

Cheers,

Pat

PS - I would have attached the model however there is a ridiculous limit of 99.7kB on the upload zip file size. It turns out a single node, single pipe, single outfall model is larger than this...

Robert Dickinson
September 18, 2015, 06:33 PM
Hello Pat,
You can email us you particular model to support@innovyze.com - there is a a 20 MB limit for those emails. It sounds me that you have two patterns of the same type - such as two hourly patterns - if the same type is found then the last found column is used. Here is an image of an hourly times a daily pattern that works fine for me. If you send us the model we can find out what is happening with your model.
Regards,
Robert Dickinson

159

Patrick_Tunnah
November 9, 2015, 02:11 AM
Hi Robert,

Thanks for helping previously with this issue - the latest v14 update seemed to do the trick as suggested via email.

I now have another annoyance with the DWF patterns in H2OMap SWMM. Do the 'Hourly' patterns only work on weekdays? It seems to be that way with any model I run, but I'm sure it hasn't always been like that... If so, it's misleading calling them hourly in the program. It would also mean that for any simulation covering both a week day and weekend day, we would be forced to create a second identical pattern of a 'Weekend' type.

Cheers,

Pat

Robert Dickinson
November 9, 2015, 05:20 AM
Hi Robert,

Thanks for helping previously with this issue - the latest v14 update seemed to do the trick as suggested via email.

I now have another annoyance with the DWF patterns in H2OMap SWMM. Do the 'Hourly' patterns only work on weekdays? It seems to be that way with any model I run, but I'm sure it hasn't always been like that... If so, it's misleading calling them hourly in the program. It would also mean that for any simulation covering both a week day and weekend day, we would be forced to create a second identical pattern of a 'Weekend' type.

Cheers,

Pat

Hello Pat,

The previous way the patterns worked was:

Flow = flow average * hourly pattern * weekend pattern * monthly pattern * daily pattern for Saturday and Sunday

The weekend had two hourly patterns multiplied together

Flow = flow average * hourly pattern * monthly pattern * daily pattern for Monday to Friday

Due to an EPA change for EPA SWMM 5.1 the pattern for both hourly and weekend should both have mean value of 1. In H2OMap SWMM v12 and before the hourly * weekend pattern had to have an average pattern value of 1.

Your comment is correct.

Regards,
Robert Dickinson