Damages Evaluation, Periodic Floods, and Local Sea Level Rise: The Case of Venice, Italy

The chapter discusses the relationship between the evaluation of the damages due to periodical coastal floods and the local sea level rise (LSLR) in the town of Venice, Italy. First, it discusses how the periodicity of sea level oscillation and the randomness of storm surge can be modeled and converted into an economic value of the damages, on the basis of the specific characteristics of the case considered and data availability. Then, a specific example is presented, namely the evaluation of the system of mobile dams, called Mo.S.E., currently under construction, designed to protect Venice from the periodical floods known as Acqua Alta (AA). The future patterns of AA are simulated for the next 50 years under alternative LSLRs. Benefits of Mo.S.E. are calculated by specifying the damage function that converts each avoided AA episode into economic values. It is shown that benefits are just at the level of the costs, when a low LSLR is assumed, and increase with LSLR, provided that it does not reach a too high level.