The EAD is calculated as (Olsen et al. 2015):
6where Ti denotes the ith return period being considered and Di the total damage corresponding to return period Ti. Throughout all analyses, return periods of 2, 5, 10, 20 and 100 years are used as recommended by Olsen et al. (2015). The total cost of flood damages are in this study calculated as a function of water depth for roads and buildings of both residential and commercial categories. For residential buildings, we further distinguish between structural and content damage in the building. The costs and depths used in the damage functions are specified in Table 1.
Table 1
Thresholds for damage to different types of structures and costs
| Type | Threshold for damage | Cost range |
|---|---|---|
| Building – Commercial | 10 cm (210) | 162–852 AUD/m2 |
| Building – Residential | ||
| Content damage | 10 cm (300) | 7,200–53,400 AUD/building |
| Structural damage | 20 cm (300) | 40,751–190,171 AUD/building |
| Road | 30 cm | 3.71 AUD/m2 |
| Type | Threshold for damage | Cost range |
|---|---|---|
| Building – Commercial | 10 cm (210) | 162–852 AUD/m2 |
| Building – Residential | ||
| Content damage | 10 cm (300) | 7,200–53,400 AUD/building |
| Structural damage | 20 cm (300) | 40,751–190,171 AUD/building |
| Road | 30 cm | 3.71 AUD/m2 |
Numbers in brackets specify the water depth where the maximum damage cost occurs.
Damage cost are obtained from Olesen et al. (2016)