Evaporation elements

Managing rainwater run-off near the surface promotes the recirculation of water into the atmosphere. In Denmark, average potential evaporation is estimated at 530 mm per year. If water is available, actual evaporation is the same as potential evaporation. In other words, the evaporation and transpiration from soil and plants in a WSUD element can be as much as 530 l per m² water surface per year if water is plentiful. By planting bushes and trees with deep roots, the actual evaporation can match the potential evaporation for longer intervals during periods of dry weather, and thus help thoroughly dry out the WSUD element.

Figure 1: Evaporation (Pictogram: Marit Reisegg Myklestad)