I am getting started with SEUWS and water balance would be my focus.
As I went through the tutorial, I noticed that the indicated annual water balance in the tutorial05.ipynb ( P + I = E + R + D + dS) is not true. Instead, the output suggested that P + I = E + R + dS, meaning that drainage is not included directly, but maybe embedded in the runoff (suggested by the model structure illustrated in Figure 1 from Järvi et al 2011). It would be great if you could confirm this.
Additionally, the individual runoff elements (ROImp, ROVeg, ROWater) were all 0 while the total runoff RO is not. I wonder if I missed sth.
Hi @LeaGu, welcome, and thanks for the careful check. You’re right, and the tutorial is wrong here.
Drainage is water draining out of each surface’s store, which SUEWS then redistributes within the grid (to other surfaces, the soil store, or runoff). It is already contained in RO and TotCh, so subtracting it again double-counts, hence the -725.5 mm residual. P + I = E + RO + dS is the correct closure, and I’ll get the tutorial fixed.
The zero components are expected in the sample run. Runoff from the land surfaces goes into the pipes first (ROPipe), and only spills into ROImp/ROVeg when PipeCapacity is exceeded, which never happens here (capacity 100 mm against a peak of about 1.5 mm per 5-minute step). So RO equals ROPipe throughout. At your own site, also watch ROSoil, the overflow from soil stores during sideways soil-water exchange: it is zero in the sample but sits outside RO.
