Seite - 197 - in The Power of Urban Water - Studies in premodern urbanism

ChristianRohr 12 Ice Jamsand their Impact onUrbanCommunities fromaLong-termPerspective (MiddleAges to the 19th Century) Abstract: Ice jams and subsequent floodswere among themost disastrous events for riverside cities in pre-modern times. An ice jam could cause thewater to rise very quickly and in some casesmuchhigher thaneventheworst summer floods.Urbanquarterscouldbe floodedrapidly andwith little timeforanyrescueactivities for theafflicted inhabitants.The lowwater tempera- ture made it nearly impossible to survive in the floods. This paper examines ice floods in a long-termperspective to seehowurbancommunities inEuropeperceivedandadapted to those dangerous hazards. After an overview of the sparse records from theMiddle Ages (still to be researched systematically), three single events from Early Modern Times are highlighted. By looking at the disastrous ice floods of 1573, 1784 and 1830 in the cities of Krems andVienna, both situated along theDanubeRiver inmodernAustria, thedevelopment of coping strategies and the emergenceofmemory cultures in anurbancontext are outlined. Introduction Ice jamsandsubsequent floodsareamongthemostdisastrousevents thatcanoccur inriverside cities.Within the field of historical disaster research, however, theyhave been remarkably ne- glected.Thispaper contributes to the fieldbyshowing thepotential for studiesdedicated to ice jamsand their consequences inurbancontexts. It beginswithgeneral considerationsondisas- ter perception andmanagement, followedby basic information on ice jams and ice floods, in- cluding a short overviewof the state of the art inmanaging them. The examples consist of an overview of records from theMiddle Ages, aswell as three examples from theDanube region in Austria: the ice flood of 1573 in Krems (Lower Austria), the central European event of 1784 with a focus on the situation inVienna, andonce again an ice flood inVienna that tookplace in 1830. This research focuses on the reconstructionof the events, the relevantmanagement strate- gies with an emphasis on the actors involved, and the memory cultures deriving from the events, leading in somecases to long-timepreventionandadaptationmeasures.Byconcentrat- ingontheice jamsof1573,1784and1830,different typesofsourceswillbepresented:adetailed petition to theEmperor togainhelp, instrumentalmeasurements in combinationwithnewspa- per reports, and finally pictorial evidence showing details of coping strategies not otherwise documented. The long-term perspective applied will help to show a) which areas of the city were hit repeatedly due to the topography of the river and the cityscape; b) how adaptation strategies weredeveloped,andwhat theywere;andc)howtheactors involvedchangedordidnotchange with regard to their vulnerability and responsibility. The period under examination extends to the first half of the 19th century; since then, stratifications andwarmeffluents from industrial complexes, aswell as a general warming after the end of the so-called ‘Little Ice Age’ (1300– 1850)havemade ice floods inWesternandCentral Europa less likely. OpenAccess.©2020ChristianRohr, publishedbyDeGruyter. Thiswork is licensedunder theCreative CommonsAttribution-NonCommercial-NoDerivatives4.0 License. https://doi.org/10.1515/9783110677065-012