Land Cover – Surface Roughness

Surface roughness, in the form of Manning's M, is set according to the land cover type, as specified in the table below. Currently these values are only used by Core+ DynamicFlood.

Land cover typeMannings MNotes
Bare land5
Water50
Other paved40
Snow-ice10
Shallow vegetation5
Dense vegetation2
Farmland10
Paved road50
Unpaved road40
Bare rock10
Building50Not used
Unclassified5

Note that in Sweden the default Manning's M values are slightly different, in order to align with national recommendations. See the country specific section for Sweden for the values and reference.