5. Flood Risk and Land Resilience: a Socio-Systemic Approach to Valuation

Proceedings of the 19th IPSAPA/ISPALEM International Scientific Conference Napoli (Italy) July 2nd - 3th, 2015

FLOOD RISK AND LAND RESILIENCE: A SOCIO-SYSTEMIC APPROACH TO VALUATION Salvatore Giuffrida 1 Giovanna Ferluga 2 Maria Rosa Trovato 1 1 DICAR, University of Catania - Italy 2 Professional Abstract. Natural calamities seriously affect the issue of the implementation of economicvaluation in land policy. Referring to the case of the flood in the Messina territory in 2009, whose damage was largely caused by the progressive loss of resilience of the land due to the over-exploitation of the ground by the anthropic settlements, the study proposes a valuation pattern based on the “imputed preferences�, aimed at comparing the economic commitment of the regional competent authorities with the financial amount of the damage and the required funding. Such a patrimonial valuation involves the consideration of the intertemporal solidarity as defined, described and measured by the social discount rate envisaging the kind of goods involved, the dynamic of social preferences and some different hypotheses about the social inter-temporal preference rate.

Keywords: damage by natural disasters; imputed preferences; social rate of discount; social capital; proactive policies.

1 Introduction Natural calamities are events posing extensive economic-evaluative problems due to their complexity. This is due on the one hand to forecasting difficulties, on the other hand to the combination of emotional aspects and political, administrative and professional responsibilities.

They are often caused by an insufficient territorial management, an overexploitation of the hydro-geological support beyond its natural carrying capacity, and the underrating of the consequences of the alterations.

Luhmann (1996) defines risk as probable damage consequent to decisions, and danger as probable damage due to external factors, i.e. the environment. The difficult delimitation between these two components in the intertwining and in the ramification of the modifying actions and the land maintenance faults requires a stronger and more authoritative presence of the central institutions that, by means of a greater distance from local interests, can affirm global values.

Proactive policies require indeed the coordination of a strong evaluation system and an organic decisional process, capable of redistributing on the whole community (extended to the supra one as well) the charge of environmental risk.

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Salvatore Giuffrida, Giovanna Ferluga, Maria Rosa Trovato. Flood Risk and Land Resilience: a Socio-Systemic Approach to Valuation

In technical terms risk is the product of three components: dangerousness or probability that the event occurs, exposure, i.e. the value of the elements at risk, and the vulnerability of these elements, i.e. their capability of bearing the strain produced by the intensity of the event. Proactive policies address the reduction of vulnerability, but the amount of the investment is always to be compared to the value of the social capital, whose valuation admits different hypotheses, not only of method, but also concerning the function and the meaning itself these policies take on in the more general economic perspective of these territories.

2 Fluctuations The proposed study concerns the territorial context of the hill and coastal centres located alongside the streams of the Ionian Sea side of the Province of Messina, and in particular the area hit by the flood on 1 October 2009. It is a very large complex of territories formed by 10 districts of the Messina municipality, four districts of the Scaletta Zanclea municipality, and five districts of the Itala municipality. The area is located on the Ionian Sea side, compressed between the coastline and a hill system cut through by a streams system directing precipitations to the sea. It is an ancient hill farming system still proud of its rare and fine plantations that has progressively lost competitiveness mainly due to the disadvantages of a sloping and narrow land crossed by the railway line and the motorway. The development of the local mobility has fostered the progressive building densification on the water-front, causing the obstruction of the main channel outlets to the sea of the exceeding rain water.

This massive construction activity on the coast has diverted huge investment quota from the delicate primary sector towards the seasonal real estate one of the second homes on the coastline. This sector is to a certain extent parasitical, not only referring to the affected hill and coastal areas, but in economic terms as well, that means concerning the revenue surplus formed in the strongest urban contexts and capitalized in the seaside homes.

The flood has caused landslides, flooding of rivers and creeks and building floods, with 31 dead, 6 missing, 122 casualties and 2019 people evacuated.

Several PM Decrees and Orders by the Special Commissioner for the Emergency have disposed the population evacuation interventions, the financing for the direct assistance interventions, a plan for the accommodation of the homeless, a plan for the restoration of the damaged buildings, subsidies for the local economic activities, the suspension of tax provisions, the delimitation of the hydro-geologic risk areas.

The financing comes from different sources: Sicilian Region, Underdeveloped Areas funds 2000-2006 and PAR FAS 2007-2013, Environment Ministry. The intervention program amount is €320m € distributed as follows: €20m for reimbursements to residents and businesses; €25m for reimbursements for the damaged buildings; €10m for the dwellings; €15m for urbanizations and 30

Proceedings of the 19th IPSAPA/ISPALEM International Scientific Conference Napoli (Italy) July 2nd - 3th, 2015

networks; €22m for the assistance to the population and the management of the commissioner’s structure; €15.4m for the first emergency phases; €212.3m for securing. In this occasion, in 2010, the Plan for the Hydrogeological Arrangement has been updated: in the hit area 291 more instabilities (added to the previous 274 ones) have been surveyed, for a total of 565 ones in a 665,19 ha area. The PAI indicates among the priority goals for the risk mitigation: - attenuation of vulnerability through the realization of supporting and reinforcement works or the realization of “passive protection” works; - realization of consolidation and hydraulic-forest works aimed at reducing the dangerousness of the surveyed instability areas; - reduction of the risk conditions through the limitation of the building activity and/or the displacement of buildings and inhabited areas.

The analysis of the landslide phenomena has led to the surveying of various instabilities and the delimitation of areas according to five ranges of dangerousness: very high (P4) with 69 instabilities on 157,91 ha; high (P3) with 230 instabilities on 196,67 ha; medium (P2) with 151 instabilities on 304.27 ha; moderate (P1) with 108 instabilities on 56.49 ha; low (P0) with 7 instabilities on 11.20 ha. The single elements at risk with the related attention levels have been delimited. The whole area is divided in the following Areas at Risk: very high (R4) n. 195 on 26.74 ha; high (R3) n. 148 on 9.96 ha; medium (R2) n. 150 on 9.66 ha; moderate (R1) n. 53 on 3.37 ha (fig. 1).

Landslides Comune Alì Alì Terme Itala Messina Scaletta Zanclea tot.

n.

(Ha)

instability index (%)

39 28 45 406 47 565

38,4 20 63 467 76,3 665

3,63% 3,88% 5,84% 3,27% 15,30% 31,9%

Geomorphological Hazard P4 n.

3 5 11 34 16 69

(Ha) 3,1 17,9 29,7 75,6 31,7 158

P3 n.

7 17 14 178 14 230

(Ha) 5,37 13,1 20,3 132 25,8 197

P2 n.

13 4 11 114 9 151

(Ha) 26,39 1,16 16,05 237,3 23,37 304,3

P1 n.

16 2 9 74 7 108

(Ha) 5,5 1,3 4,0 41,7 4,0 56,5

Risk P0

n. (Ha)

Total

n.

(Ha) n.

39 40,3 9 28 33,5 7 45 70,1 16 6 10 406 496,9 138 1 1,1 47 85,8 25 7 11 565 726,5 195

R4 (Ha) 1,23 2,34 1,85 17 4,05 26,47

R3 n.

2 12 19 89 26 148

(Ha) 0,17 0,5 2,4 5,23 1,66 9,96

R2 n.

20 5 9 100 16 150

(Ha) 1,55 0,21 0,57 6,63 0,7 9,66

R1 n. (Ha) 11 0,33

Figure 1. Area affected by the flood and articulation of damage and risk

31

Total

n.

42 24 44 35 2,35 362 7 0,69 74 53 3,37 546

(Ha) 3,28 3,05 4,82 31,2 7,1 49,5

Salvatore Giuffrida, Giovanna Ferluga, Maria Rosa Trovato. Flood Risk and Land Resilience: a Socio-Systemic Approach to Valuation

3 Renaissance. A socio-systemic approach Territoriality is one of the most resistant and omnipresent expressions of social solidarity. According to the thought of Luhmann’s, re-red by Rizzo (1999, pp.

265-326) in economic-evaluative terms, territory is a “difference-unity between social system and environment”: the first comprises two sub-systems, the second is defined by difference, as trace of what remaining from the communicative process around the property-objects that are relevant for the social community.

The social system is constituted enacting and strengthening communicative mechanisms giving rise to a progressive referential closure to the natural, built and human environment. In this sense: natural contexts in harmony with the social system communicate with it, and therefore they are not “environment”, but “territory”; on the contrary, marginal social groups, decayed city areas, salvaged heritage, are “environment”, as they are excluded from communication.

As a result of the internal communication of the system, mechanisms of specification and differentiation of the referential closure are activated, resulting in the formation of different sub-systems aggregated around specific codes; a code works as a filter the sub-system adopts to select the components to include in order to strengthen its own closure and progressively differentiate itself from the environment and the other sub-systems; when a sub-system overrides other ones, the latter become its own environment. In this sense, the environment is defined as any aspect of reality – natural, artificial and human – receding from the position of communication subject (communication with) to the position of object (communication on): it is rejected basing on the code of the sub-system, that therefore is not existing for its own ends. Code is somehow a synonym of program, but also of value in a specific sense.

On these grounds, landscape emerges as result of a double communicativeselective-constructive process: at the level of the “environment-territory” selection, the semantic field of the “objects-properties” that may participate to the successive more specific communication level is delimited; at this second level, some sub-systems (more than other ones, and/or in competition with other ones) coordinate themselves in the progressive selection of those propertiesrelations that reveal the essence of this hyper-form, or meta-form, that is reborn as landscape. The consolidation of the position of these sub-systems inside the social macro-system defines the resilience level of landscape. This multiple movement - involving objects-properties-relations emerging as a result of the extra-systemic communication (environment-territory) and intra-systemic (subsystem1-sub-system2-…-subsystemn) in the environment-territory-landscape meta-selection process – activates constitutive functions that select the landscape entity as super-system of different sub-systems. The latter, under the selective action of this new meta-code, participate in an archipelago of landscape-sub-systems communicating to its own inside/outside through a 32

Proceedings of the 19th IPSAPA/ISPALEM International Scientific Conference Napoli (Italy) July 2nd - 3th, 2015

process of further selection, and therefore of exclusion/inclusion, that reactivates the functions of revelation-renaissance-resilience.

The extra-systemic communication is always carried out inside the social macrosystem, but it has the system as subject, and the environment as object; the intrasystemic communication is carried out inside each social sub-system, assuming as object of its own communication all the other ones. The archipelagocommunication implies a sub-systemic closure (it is necessary that each subsystem differentiates itself) and a successive opening (it is necessary that the included sub-systems share some codes in order to activate the “landscape” meta-code.

As a consequence, the monetary measure of the environmental damage according to the concept of “total economic value” (Pierce, Turner, 1991) - use values, not use and intrinsic, i.e. of values for humankind and values for nature – appears weak, because they cannot be accumulated. The former have indeed a conventional nature, while the latter are placed outside the linguisticcommunicative agreement, remaining arbitrary. In this status, as they participate in the environment, they cannot be ascribed to the realm of values. They would exist only as naked supports of a hypothetical value. An intrinsic value independent from any socio-systemic determination and assumed without the “collision” between nature and social system (fluctuation) is not thinkable indeed. Furthermore, it is not correct to confuse the environment with the natural eco-system that, as said, can belong to the social system and to the environment as well. A socio-centric vision implies instead that values of use, non use and existence should be meant as significance horizons or, according to Luhmnn, as codes, values, programs of a sub-system.

4 Revelation: appraising landscape asset Natural calamities constitute environmental fluctuations towards which the social system reprograms its communicative codes, and therefore the relation between values, valuations and actions. The evaluative approach based on the method of the Imputed Preferences and therefore of the cost sustained for the Defensive Expenses and the Restoration Cost, provides information on the physical and specific nature of the places hit by the calamity event, while it doesn’t say anything on their value. The Restoration Cost provides useful, but not exhaustive indications for the dimensioning of the proactive policies; the Defensive Expenses are difficult to control by means of the value of the involved social capital and the value of damage that capitalizes a complex ramification of irreversible effects. The methods of evaluation of the environmental damage are influenced by the prevailing, in literature (ANPA 2002; Candido et al., 2006), of an individualistic-hedonistic approach, inappropriate to represent the value of a complex “multi-intentional” system that is linked instead to a “collective rationality formed in conversational argumentative contexts” (Mercier and 33

Salvatore Giuffrida, Giovanna Ferluga, Maria Rosa Trovato. Flood Risk and Land Resilience: a Socio-Systemic Approach to Valuation

Sperber, 2011; Labinaz, 2013), born from relation, interdependence, and sharing of horizons. This type of rationality is typical of the action of the authorities for the territory protection, whose decisions – even if with the typical weaknesses of the link politics – voters – arrange in a system the individual preferences maximizing the efficiency, the effectiveness and the equity of the system itself.

Despite the Expressed Preferences concern the value of the goods and not the re-production cost alone, they appear ill-suited for different reasons: they don’t perceive the entirety and the articulation of the territorial values (Arrow et al., 1995); the procedures incur a wide range of errors (Bresso, 1995); the willingness to pay is an “out of scale” individual motivation concerning the environmental issue, the territorial policy, and the renaissance of landscape, as it measures will not taking into account duty and power. In the proposed application, the Imputed Preferences are complementary and opposite to the expressed ones, because: they concern cost and not value; they measure the effort actually made by the public subject and therefore by the community organized basing on duty and power. On the other hand, even agreeing on a “Coase” approach, according to which the safety, and more in general the safeguard of the environment constitute “a prize” for the communities that are more willing to pay for them, we shouldn’t forget that the environmental risk is nonetheless asymmetrically distributed between the territories, and that it characterizes those territorial contexts whose landscape is more significant, that are economically weaker, and inhabited by communities that are hardly available to pay. Therefore, the issue of the environmental valuation deserves to be placed again at the centre of a socio-systemic approach combining synchronic and diachronic communication.

This application intends to compare the adequacy of the public expense to the amount of the expenses necessary for the securing of the affected areas and the regeneration of the local anthropic activities. As data on the balance of the involved municipalities are not available, the public expense is represented by the expense commitments of the Sicilian Region destined to the territory and the environment through the coordinated action of several “Assessorati” (departments): The annual expense “Commitments”, the current “Expenses” and the “Expenses” in capital account, and the “loan refunds” for the functioning and the investments in “fixed social capital”.

The expenses of the Territory and Environment Department are fully accounted, and so is part of the expense of the Agriculture Department (the quota of the Forest Department); variable quota of the balance of the Region Presidency and of the Balance Department , carrying out activities concerning the functioning of the above mentioned departments, have been added to the latter; the above mentioned quota are the ratio between the expense assigned to the two departments and the total regional annual expense E, and therefore they vary annually: ; ; .

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Proceedings of the 19th IPSAPA/ISPALEM International Scientific Conference Napoli (Italy) July 2nd - 3th, 2015

The entity of this expense to assign to the reservoir of the analyzed territorial complex is proportional to the relative value of the reservoir itself, on the total of the 102 reservoirs of the whole regional territory. The reservoirs delimited by the hydro-geological arrangement plan have been characterized basing on quantitative and qualitative criteria, referring to the data included in the Guidelines of the Regional Territorial Landscape Plan.

The expense assigned to the analyzed reservoir, the n. 102, will be calculated by means of a proportionality factor that takes into account the ratio between the surface of the reservoir itself and the surface of the Region , the ratio between the linear development of the hydrographical network and the total development, and a correction factor that takes into account the value of the territorial context. The latter is calculated by means of a simplified model of multidimensional analysis that takes into account quality factors referring to: level and type of anthropization defined basing on the combination of uses of the soil and ecologic and naturalistic value, taking into account rarity, level of naturalness, cultural, landscape and environmental value; naturalistic merit, determined basing on the surface of the reservoir in SIC (Sites of EU Community’s Interest) and/or ZPS (Zones of Special Protection). The imputation index – equal to 0.0095 – applied to the regional expense of the competent departments, provides an expense flow to capitalize in order to obtain a measure of the importance of this territory from the point of view of the competent institutions. The latter have the responsibility to coordinate the codes (interests and values) of the different sub-systems forming the social macro-system.

Table 1.

Annual expenses and assignation to the hydrographical basin n. 102

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Salvatore Giuffrida, Giovanna Ferluga, Maria Rosa Trovato. Flood Risk and Land Resilience: a Socio-Systemic Approach to Valuation

5 Resilience. Social Discount Rate and intergenerational ethics Calamity may be considered as the occurrence of a sudden or big scale adversity, that disrupts the basic fabric and the normal functioning of a society/community, or an event, or a series of events, that originates victims and/or damage or losses of property, infrastructures, facilities or means of sustenance, referring to a scale the involved communities are not able to cope with without an external assistance.

In particular, in the case of an exceptional whether-climatic event, natural action can cause bad injuries, on the hydro-geological point of view, on built heritage, infrastructures and human lives. To quantify such natural cause damage it is necessary to evaluate the effects on the different components of the territory, and the actions of restoration, mitigation, prevention and management of the calamity with measures of long term risk reduction. As such actions refer to different spans, their quantification deals with the problematic issue of the actualization of the damage effects on the various components. The choice of the discount rate r to support the actualization operation is a delicate moment of the analysis, and implies inter-temporal efficiency, intergenerational equity and sustainability.

The current action value turns out to be strongly influenced by the r discount rate value. A high value of the latter tends to make the current value (representing an actualized value of a time distant value) very low; a value of the discount rate close to zero makes appreciable values referred to very time distant t as well; a 0 rate value ignores completely the temporal dimension, as it is possible to compare directly values referred to very different moments. The choice of the discount rate value and therefore of the discount factor value, that represents the weight attributed to a value referred to a distant time t moment, turns out to be strategic in any evaluation process. In particular, the more the considered span is distant, the more the value is sensitive to the time t at the variation of the discount rate. In the case of real monetary flows the choice of the discount rate descends from the opportunity-cost of the capital or of the considered resources, basing on the analysis of the financial markets (Capital Asset Pricing Model – CAPM). In the case of welfare flows produced by public goods instead, such as the environmental goods, in which the preference structure of collectivity is different from the one of the financial markets, it is not possible to deduce the discount rate basing on the opportunity cost, but it is necessary to refer to a social discount rate that takes into account the time preference rate. In particular, in the case of monetary evaluations of goods and public facilities, the value of the social discount rate is usually lower than the financial interest rates utilized in the private sector. In particular, the last years, under the incentive of a growing importance of the environmental issue, the sustainable development and the specific issue of the global warming, the scientific community has proposed new approaches and specific econometric 36

Proceedings of the 19th IPSAPA/ISPALEM International Scientific Conference Napoli (Italy) July 2nd - 3th, 2015

algorithms to support the determination of the social discount rate, capable of detecting and characterizing the inter-temporal dialectic and the intergenerational dialectic of values of goods and public facilities, basing on which it is possible to propose different sustainability models referring to the different positions.

An important point of reference to determine the discount rate in the goods and public facilities evaluation field is represented by the Ramsey’s approach (1928). Most part of the other approaches have indeed been developed starting from it, integrating the analysis for risk and uncertainty conditions as well. It is possible to resume some characteristic elements of the main macro groupings of approaches in literature for the determination of the social discount rate (De Francesco and others, 2006; 2012), that refer to a different perception of intertemporal efficiency, intergenerational ethics (Page, 1997a), sustainability, risk and uncertainty inside the same macro-area as well.

1. Positive and constant social rate (r>0). According to the economic approach, the determination of the discount rate is ascribable to the theory of utility that explains the individual/collective choices on the grounds of a system of intertemporal preferences. Basing on the empirical observation of the individual/collective behaviours, it is possible to highlight how such preferences lead to privilege net benefits that are temporally and spatially “close”, referring to temporally and spatially positive discount rates. The most diffused economic models for the optimization of inter-temporal choices assume maximization, bonded by an objective function U. Among them, it is possible to mention Ramsey’s equation (1928) and “Ramsey’s equation” after Frank Ramsey (on the descriptive and prescriptive approach as well), and the modification of Ramsey’s equation proposed by Pearce and Ulph (1999). In particular, it is assumed that the latter has an always positive concavity that turns out in a decreasing trend of the marginal utility function at the growing of consumption, and in an aversion to risk of downfalls in the consumption level. In particular, the more society is averse to inter-generational inequalities and attributes more weight to generations with lower consumption levels than to the most opulent ones, the more the function U is concave. Consequently, in a long term scenario of income growth, a lesser weight is attributed to future generations, while in case of downfall a greater weight is conferred to the latter (Hoel e Sterner, 2007).

2. Zero discounting, low discounting and Dual Rate Discounting. The assumption of the above mentioned macro-groupings is the concept of sustainable development itself, according to which the needs of the current generation are satisfied without compromising the capability of the future generations of satisfying their own necessities (WCED 1987). The commondenominator of the sustainability theories is the acknowledgement, on the one hand, of the “long term of mutual dependency of environmental quality and available resources, and, on the other, the economic development” (Van den 37

Salvatore Giuffrida, Giovanna Ferluga, Maria Rosa Trovato. Flood Risk and Land Resilience: a Socio-Systemic Approach to Valuation

Bergh e Hofkes, 1998). It is possible to individuate two main approaches concerning this issue: 1. strong sustainability, whose social discount rate is null or zero (r=0) due to intergenerational equity reasons (Broome, 1991; Page, 1977b; O’ Neill, 1993; Jones et al., 2000; Oxera, 2002), or is negative (r<0) because of intergenerational equity reasons, above all in the case of scarce non renewable resources or facts implying the production of negative long term environmental externalities that cannot be lowered by means of the current technology; 2. weak sustainability in which the positive social discount rate (r>0) may be deduced through an adjustment of the financial discount rate towards the bottom level, or by means of a double discount rate (Dual Rate Discounting) calculated using a Ramsey type equation, and determining a first rate calculated for the tangible goods, and a second rate calculated on the environmental components (Kula e Evans, 2011; Kogel, 2009; Alamansa e Calatrava, 2007). The difference between the Dual Rate Discounting – DRD and the Social Discount Rate – SDR (unique rate) value may be considered as a measure of intergenerational solidarity, as it quantifies the transfer of welfare from the present generation to the future ones (Alamansa e Martinez Paz, 2011).

3. Gamma discounting, hyperbolic discounting and social discount rate decreasing in time. These approaches are born as passing or integration of exponential discounting and, in general, of the deterministic type approach of the Ramsey’s equation. They have in common the proposition of a social discount rate decreasing in time r(t) basing on different motivations: 1. Conciliate the expectations of welfare growth with a principle of prudence justified by the uncertainty on events that are very distant in time (uncertainty on the discount rate, on the level of future growth and on life expectations) when a very long span is involved; 2. Adapt better the principle of intergenerational equity; 3. Take into account some experimental evidences on the modalities by means of which individuals make choices.

Despite the relevant scientific efforts, currently the social discount rate values utilized in each country, even in the EU zone, are different. The choice of the social discount rate values is thrust to the discretion of countries characterized by different levels of wealth, and by different environmental sensitivity and intergenerational ethics (Gollier, 2002). The European Commission currently recommends the use of a social discount rate obtained as benchmark of financial rates observed in the member states, equal to 5,5% in the cohesion countries, and to 3,5% in the most advanced ones (European Commission, 2006, 2008), allowing for different rates justifiable by specific socio-economic conditions.

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Proceedings of the 19th IPSAPA/ISPALEM International Scientific Conference Napoli (Italy) July 2nd - 3th, 2015

6 Exit The value of the environmental capital calculated under the different hypotheses of social discount rate concerning the costs of the flood indicates a disparity that grows depending on the type of utilized approach: constant, decreasing, gradually decreasing, null (fig. 3). According to the “Luhmannian” approach, the difference between the renovation cost and the assigned expenses thus calculated measures the entity of the portion of territory declassed to the status of environment.

Figure 2. Total assigned expenditure streams according to the different social discount rate hypotheses, and appraisal of the corresponding social capital landscape asset

The nature and culture of the discount rate and its effects restore the “capability of future” of a settled community. In the complex, wealthy, structured and articulated socio-territorial realities, in which the immobilized wealth assumes forms activating great expectancies of revenue and capital value earnings, the individual determinations are strongly influenced by the profile of the territorial policies that sustain economic activities and entrepreneurship, and the infrastructural and real estate heritage constitute simultaneously sources of utility, income, capital value and tax revenue. In these realms alibis about production costs do not resist, and symmetrically tolerance regarding relaxation of the calamity alert should not exist.

Summary According to Luhmann, environmental risk is connected with the weakness of: intra-seismic communication, that measures the extent the social macro-system can be considered a Unity/difference; extra-systemic communication, that measures its resilience to environmental fluctuations and therefore its capacity to differentiate from the environment, thus encompassing wider and wider areas in the internal communication. According to the current definition, risk can be defined as the probability of potential impacts affecting the whole of the habitat depending on hazard, vulnerability and exposure. Resilience is the general target of a prevention policy; it makes vulnerability decrease, and it is defined as the ability of an 39

Salvatore Giuffrida, Giovanna Ferluga, Maria Rosa Trovato. Flood Risk and Land Resilience: a Socio-Systemic Approach to Valuation organized system to return to the previous status; as such resilience is a piece of the social capital consisting of facilities, know-how and interventions reducing vulnerability. In the feedback of the flood event in the Ionic sea side territory of the Province of Messina, we propose a patrimonial type of valuation approach trying to integrate the characteristics of dangerousness, risk and vulnerability according to the Sicilian Region’s Hydrogeological Layout Plan (HLP), in a valuation of damage model inspired by the method of the “imputed preferences”, aimed at comparing the commitments of the competent authorities for the safeguarding of the territory and the actual restoration costs. This valuation strongly involves the social discount rate as a central issue of sustainability, whose dimension, articulation and temporal variation provide relevant issues for land safeguard policy with regard to the intertemporal solidarity and to the renaissance of the affected local communities.

Acknowledgements. Salvatore Giuffrida edited paragraphs 1, 3, 4, 6; Giovanna Ferluga edited paragraphs 2; Maria Rosa Trovato edited paragraph 4. Image in fig. 1 is by prof. M. Navarra.

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Proceedings of the 19th IPSAPA/ISPALEM International Scientific Conference Napoli (Italy) July 2nd - 3th, 2015 15. Rizzo, F. (1999). Valore e valutazioni. La scienza dellâ&#x20AC;&#x2122;economia o lâ&#x20AC;&#x2122;economia della scienza. FrancoAngeli, Milano.

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Salvatore Giuffrida Department of Civil Engineering and Architecture University of Catania, Italy E-mail: sgiuffrida@dica.unict.it Giovanna Ferluga Professional E-mail: gio.ferluga@hotmail.it Maria Rosa Trovato Department of Civil Engineering and Architecture University of Catania, Italy E-mail: mrtrovato@dica.unict.it

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Salvatore Giuffrida, Giovanna Ferluga, Maria Rosa Trovato. Flood Risk and Land Resilience: a Socio-Systemic Approach to Valuation

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