SWMM RTK Unit Hydrograph Dialog Box
You create SWMM RTK unit hydrographs in this dialog box. The dialog box contains a list pane with the following controls:
The table on the top right allows you to define the default RTK and initial abstraction depth for all months. The first row is used to specify parameters for a short-term response hydrograph, the second for a medium-term response hydrograph, and the last for a long-term response hydrograph. It contains the following columns:
R | The fraction of rainfall volume that enters the sewer system. |
T | The time from the onset of rainfall to the peak of the UH in hours. |
K | The ratio of time to recession of the UH to the time to peak. |
Dmax | The maximum depth of initial abstraction available (in rain depth units). |
Drec | The rate at which any utilized initial abstraction is made available again (in rain depth units per day). |
Do | The amount of initial abstraction that has already been utilized at the start of the simulation (in rain depth units). |
The table at the bottom allows you to override the default RTK and/or abstraction depth for specified months. To override the default value, check the box for the corresponding row to enable the values in that row to be edited.