Designing pipes for no surcharge criteria

Step-by-step:

Once you have decided on which rainfall methodology will work for your site, you can begin to create the drainage network in your model, starting with the no-surcharge state.

The example model already has catchment areas set up, with a manhole in each and pipes connecting the manholes. The flow arrows between the pipes designate the flow direction.

Ensure the rainfall data has been configured with the FSR parameters, return periods and storm durations by loading the rainfall data:

1. On the ribbon, Rainfall Pollutants tab, Rainfall panel, click Rainfall Manager.
2. In the Rainfall Manager toolbar, click Open.
3. Browse to and open the file design rainfall.idrx.
4. Click OK.
   
5. Click OK to exit the Rainfall Manager.

Now, it is time to size the pipe correctly for the no-surcharge state, or Stage 1:

6. On the ribbon, Preliminary Sizing tab, Network Design panel, click Network Design Criteria.
7. In the Network Design Criteria dialog box, Flow Options tab, enable From Library.
8. Expand the drop-down and select Rain 1.
9. Keep the Time of Entry set to 5 minutes.
10. Set the Maximum Travel Time to 30 minutes.
    
    
11. Click the Design Options
12. For the Pipe Size Library, select Default.
13. Optional: If you have your own library of pipe sizes, you can click the Browse (…) button, select the file, and load the library.
14. Expand the Lock Slope drop-down and select None.
15. Expand the Design Level drop-down and select Level Crowns (Soffits).
16. Set Slope to 500.
17. Set Slope to 40.
18. Enable Check Velocity.
19. Set Min Velocity to 0 m/s.
20. Set Max Velocity to 0 m/s.
21. Deselect:

• Allow Backdrops
• Limit Pipe Full Conditions
• Use Flow Restriction
• Reduce Channel Depths
• Exclude Branch Lines
• Apply Offset

22. Keep the option to Allow Manhole Sizing
23. Optional: If you have your own Manhole Size Library, you can click the Browse (…) button, select the file, and load the library.
24. Click OK.