# a) floods

Fluvial, pluvial, and sewerage floods are considered the primary types of flood, which form the building blocks for other types of floods. Using global hazard maps for fluvial and pluvial floods, our current physical risk models cover fluvial and pluvial floods only.^{[1]}

There are 32 damage functions used for flood calculations across 66 TICCS asset subclasses. These damage functions for floods follow the general logic of:

*DF=C*(D ^{P}),*

where *DF* is the damage factor representing the percentage of asset value lost, *C* is a parameter that captures the relationship between hazard intensity and overall vulnerability of assets, *D* is the hazard value represented by flood depth, and *P* is an exponent that explains the shape of the relationship between hazard value and overall vulnerability of the assets.

_{[1] Not all types of floods can be modelled effectively with the desired level of accuracy. For example, glacial lake outbursts, flash floods, urban floods, and coastal floods are caused by a myriad of interacting and compounding factors such as sea level rise, sewerage capacity, and topography, among others.}