20thcentury archaeologicalsurveying archaeology archaeologyandstate architecture architectureandsociety architectureetsociété archéologie archéologiepréventive aspectdel'environnement barrages conceptionetconstruction conservationandrestoration dams designandconstruction environmentalaspects general histoire historicpreservation history italy local politiquegouvernementale prospectionarchéologique riverbasinsurveys salvagearchaeology sitesdupatrimoinemondial socialscience state unitedstates watersheds worldheritageareas