Runoff coefficient

Constant for calculating the rainwater runoff for different substrates. Impermeable subsoil: C = 1, fully permeable subsoil C = 0.

Symbol or abbreviation:

C
The runoff coefficient C is differentiated according to:
  • CS: Peak runoff coefficient for calculating the runoff effective area (AU) for dimensioning roof drainage and underground pipes.
  • Cm: Average runoff coefficient for calculating the volume of rainwater retention areas (VRRR).