4.3.2. Detailed Assessment Results

In the Barcelona case study, the technical and economic assessments were carried out for the proposed adaptation scenarios related to flooding and CSO reduction strategies. The economic damage assessment provided the expected annual damages (EAD) for each scenario. Comparing the scenarios against the BAU, the avoided damage was estimated for each adaptation scenario. These were accounted as benefits in the CBA. Ecosystem services were included as benefits provided by the SUDS measures thus present in all adaptation scenarios. Costs were estimated for the adaptation scenarios, adjusting the previous estimates for individual measures of the CEA to the new adaptation scenarios. Net benefits were obtained in the CBA for each scenario.

Furthermore, for the flooding reduction strategy, estimates from the intangible damage assessment gave the percentage of high-risk area reduction for pedestrians and vehicles for each scenario.

In the Bristol case study, a detailed analysis of the proposed adaptation scenarios was undertaken using a different approach. Stakeholders were more interested in the potential impacts of different intensities events for two scenarios and compare them to the BAU. Measures were ranked based on the total damage costs expected during a range of extreme flood events in the city. The assessment was calculated by developing a baseline of expected flood damages during a flood event in the future, and comparing them to the expected flood damages with property level protection applied to targeting buildings or strategic zones.


