Seite - 251 - in The Power of Urban Water - Studies in premodern urbanism

15 Human Impact onHydrology 251 Fig. 3:Mapof theDanubenear Ingolstadt. The Danube valley close to Ingolstadt was characterized by ameandering river course which entailed a large number of backwaters (Fig.3).5 Ingolstadtwasmentioned at the beginning of the9thcentury for the first time. Itwassituatedona lowterrace to thenorth,close to themouth of the Schutter brook. The situation provided locations formills, but also direct access to the Danube river as an important line of transport. However, in Roman and earlymedieval times the course of the Danube was some kilometres south of Ingolstadt. In pre-Roman times, the oppidumofManching6was locatedopposite the later townonthesouthernbank,probablyalso because the Danube was used as an important transportation route. This southern Danube coursewasnavigable inRomantimes,as theshipsdiscovered inOberstimm7show.Close to the IronAge oppidumofManching,water courses of theDanubewere still active even in the Late MiddleAges.8 It isaninterestingquestionastowhether thesechangesof theregionalhydrology were theresultofnatural floodsorofartificialwaterchannelling.However,within thesouthern part of the town of Ingolstadt, urban archaeology shows some intentional changes of water coursesby land filling andbank stabilisation.9 Both examples lack detailedmodern geoarchaeological data for verifying themedieval to- pographyand landscapechanges.Relevant informationcomes fromriver sediments,whichare not protected as archaeological sites, because their anthropological character is often hardly obvious. Furthermore, the redirectionof river systemsmayhave takenplace far away from the towns themselves andare thusoutside the remit of urbanarchaeology. Excavationsat theDonaumarkt inRegensburgbetween2009and2015allowthereconstruc- tionof thedevelopment of anurbanquarter at thewaterfront.10 They showed the change from a floodplain situation, to some harbour and canal constructions and to a landfill in the 12th/ 13thcenturies,whichprovidedthegroundforurbanstonearchitecture.Over thecenturies, there have beenmany floods and their sediments are partially visible in the archaeological record11 (Fig.4). A flood in 1304 causedbasic changes to thenorthernwaterfront opposite the city. The 5 Schmidt–Riedel 2008, fig. 206. 6 Guichard et al. 2000. 7 Bockius 2002. 8 Schramedei –Brunnacker 1992, 427. 9 Arauner 2008. 10 Nießen–Wollenberg 2019. 11 Codreanu-Windauer et al. 2008.