Terms for R
Rain downpipe / downspoutRainwater
Rainwater centre
Rainwater containment
Rainwater harvesting
Rainwater infiltration
Rainwater management
Rainwater pipe
Rainwater tank
Rainwater treatment
Receiving water courses
Replenishing / system control
Retention
Retention cistern
Retention volume
Rodent guard
Roof runoff water
Runoff coefficient
Terms 1 to 18 from 18
Runoff coefficient
In wet weather evaporations and partial infiltration of the collecting surfaces reduce the runoff volume. The runoff coefficient is a factor dependent on the collection surface, by which the accumulated rainfall is multiplied to obtain the actual rainfall runoff introduced into the drainage system. Alternatively, the runoff coefficient is the factor by which, depending on the type of surface, the effective impermeable area is calculated. For example, it is 0.9 for metal or tile roofs and up to 0.3 for green roofs.