�Basic relationship: (assuming
no change in water level)
�runoff
+ direct inflow + precipitation = evaporation + outflow
Inflow
Outflow
Precipitation
Evaporation
From an annual perspective,
the water level of a lake is in equilibrium, meaning that the water addition
(through runoff, direct inflow, and precipitation) is equal to the water
lost (through evaporation and outflow). These volumes of water are
calculated by multiplying the land area they refer to by specific
coefficients.
Determining the outflow is
the ultimate goal as it relates directly to the flushing rate.