Target discharge for emergency drainage

The target discharge for the emergency drainage system corresponds to the discharge capacity of the emergency drainage system, taking into account the event of the century. In addition to the event of the century, the calculated rainfall is also taken into account for dimensioning. In pressure drainage systems, the actual discharge is set after dimensioning and hydraulic balancing.

A distinction is made between two different cases when determining the target discharge. On the one hand, whether the entire event of the century is to be drained via the emergency drainage system and, on the other hand, whether only the difference between the event of the century and the calculated rainfall is taken into account as the minimum drainage capacity in the dimensioning. Depending on the case, the event of the century r_(5,100) in l/(s*ha), the rainwater runoff r_(D,T) in l/(s*ha), the peak runoff coefficient C_S and the precipitation area A in m² are taken into account when calculating the runoff volume flows.