There was a change in EPA SWMM 5.1 to better represent Weekend vs Weekday Hourly flow patterns

There was a change in EPA SWMM 5.1 to better represent Weekend vs Weekday Hourly flow patterns

Fields for the DWF Tables in H2OMap SWMM and InfoSWMM are:

1. Scenario Name
2. Junction ID for the node that receives the DWF
3. The item – either FLOW, MASS or Concentration (Use Blockedit to just set this at Flow for all Rows) and you should fix your problem.
4. Value – the flow in the units defined in the Run Manager
5. Pattern1 – Can be Weekend, Hourly (Weekday only), Monthly or Daily patterns.  They can be in any order but Hourly only applies Monday to Friday.
6. Pattern2 – Can be Weekend, Hourly (Weekday only), Monthly or Daily patterns. They can be in any order but Hourly only applies Monday to Friday.
7. Pattern3 – Can be Weekend, Hourly (Weekday only), Monthly or Daily patterns. They can be in any order but Hourly only applies Monday to Friday.
8. Pattern4 – Can be Weekend, Hourly (Weekday only), Monthly or Daily patterns. They can be in any order but Weekend only applies to Saturday and Sunday.
9. Alloc Code which is a tag from the DWF Allocator

It used to be that the two hourly patterns were applies as

… the week end flows are generated in the model by multiplying Node DWF x Hourly x Weekend x Daily x Monthly. 

But now

… the week end flows (Saturday and Sunday) are generated in the model by multiplying Node DWF x Weekend x Daily x Monthly. 

… the daily flows (Monday to Friday) flows are generated in the model by multiplying Node DWF x Hourly x Daily x Monthly.  

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