ArcheoRisk: a Decision Support System on the Environmental Risk for Archeological Sites in the Venice Lagoon

More than 250 submerged archaeological sites were identified in the Lagoon of Venice, which account for an historic and artistic heritage of extraordinary value. These sites are endangered by several environmental and human factors: erosion, chemical pollution, organisms (mainly wood borers), motor-boat traffic, fishery activities, and robbers. A Decision Support System (DSS), named ArcheoRisk, was developed to include the safeguarding of archaeological sites within the environmental management of the Venice lagoon and to select most effective safeguarding/rehabilitation interventions, whenever needed. The DSS relies on a Geographical Information System platform (Arcview) and is composed of two modules: (1) assessment of archaeological risk, (2) selection of interventions. An environmental-archaeological georeferenced database was constructed and an environmental risk assessment methodology for archaeological sites was developed, based on the conventional source-pathway-receptor scheme. The two-steps procedure includes (1) Screening Risk Assessment and (2) Site Risk Assessment. Screening Risk Assessment provides risk maps and priority of intervention based on risk sources and archaeological sites location and value. Site Risk Assessment is a ranking procedure requiring the user to fill a scoring questionnaire about type of risk sources, exposure and material vulnerability of artefacts present at the site. Based on the risk assessment, the selection of intervention (investigations and safety measures) is supported by an Intervention Selection Matrix, i.e. environmental features vs risk types, and an archive of intervention costs. In its prototype format, the ArcheoRisk DSS is being submitted to a wide testing activity and will be adopted by the Cultural Heritage Authority in Venice for communication, programming, and planning of interventions. It can be easily applied to different case studies and environments, thus providing a promising reference of GIS-based DSS and risk analysis application for the integrated management of environmental and cultural heritage.