La valutazione economica del beneficio idraulico derivante dalle opere e dalle attività di bonifica nella regione del Veneto

In Italy, and in particular in the Veneto region, Reclamation Consortia (Consorzi di Bonifica), i.e. local Authorities in charge of reclamation and drainage of water, have always played an important role in land and water resource management. Starting from the sixteenth century, when the Republic of Venice recognized the “public utility” of reclamation and started a systematic and widespread organization of water management in the Veneto Region, it became a crucial issue both the construction and management of infrastructures devoted to the reclamation activities and the drainage of water and the sharing of the relative expenses among final users. Therefore the debate about the definition and the estimation of the benefits deriving from the Reclamation Consortia’s activities has been widespread in the literature and open to further discussion according to the continuous changes in the legislation. Recently many Italian Regions promulgated Regional Laws and set new criteria for the identification of benefits generated by reclamation and drainage of water and the sharing of expenses among users. These estimations are usually difficult and very expensive to be carried out because of the extensions of the areas where the local Authorities operate, the great number and variety of properties and the dynamic of local economies involved. It is often the case that Reclamation Consortia which have to charge users in order to recover from the costs they bear, have scarce financial resources and information to implement refined evaluation models of the benefits generated. We present a model to evaluate, according to mass appraisal approaches, the benefits and the increase in property value generated by the reduction of risk of flooding characterized by different return periods (i.e. 5 years and 50 years respectively). The intuition is that the benefits are equal to the damage avoided because of risk reduction in the presence of infrastructure and related activities operated and managed by the Reclamation Consortia. The model requires low information gathering costs and provides robust estimates.