Annual damage potential

The occurrence of flood events is a stochastic process. As logical consequence the potential damage can not be exactly determined. The calculation is based on available statistical data and is expressed as annual flood damage potential. Therefore the damage is weighted by the frequency of returning.

Assumption: The maximal damage is set as the upper limit of integration (recurrence interval T_¥ = T_max); the expected damage can only be calculated for events which probability of occurrence is more frequently than T_max. The corresponding probability for this design event is P_max As consequence the remaining risk cant be considered.

The flood damage potential is a function of flooded area, land use and water depth. It is summarized in the following formula:

For solving this equation, it is necessary to calculate the potential damages for flood events of different estimated probabilities.

• input data: water depths for each flood event
• damage functions
• result: damage potential

Total damage potential

Integration of all damage potential values (assuming linear function of damage)

Applying this method the combination of flood probability and monetary damage assessment is managed. The flood risk can be estimated based on annual flood