Sewer Storage not represented correctly
I've been trying to account for sewer storage in one of my projects. As an example, I've added three sewer areas to my project, covering 188 ha (according to GIS). I've assigned a storage of 5 mm and a pump speed of 0 m3/s. When I select overlays -> add areas, I can see clearly that importing these areas went correctly. However, when I assess my mass balance, the sewer storage barely functions: it fills only with 1675 m3 (0,9 mm) of rainfall after a 60 mm storm event.
What could be wrong here?
- I've set all sewer connection function values to 1.0 (to be able to assess the mass balance).
- The sewer areas clearly cover all of the terrain that I'm assessing.
- All sewer areas are checked as 'active in simulation'.
- I've re-run and re-imported the files multiple times
- The calculated value does not coincide with the expected storage in only one of the sewer areas.