Marek Grześ

Abstract

Ice jamming phenomena on rivers in temperate and high geographical latitudesare often the cause of severe floods. Water level rises caused by ice jams areviolent and difficult to forecasting. Information on this subject is still very scanty(Bolsenga 1968; E. R. Ficke and J. F. Ficke 1977; Michel 1971). In a great majorityof cases accurate pinpointing of the site and height of the jam water level rise isvery difficult. This kind of research should therefore be proceeded by listing the icejamming phenomena on a given river as the basic starting material for fixing thejamming river reaches and for planning hydro-power stations (Williams and MacKay1973). An engineer is now always faced with the difficult job of estimating a priorithe rise in water level as a result of ice formation.The necessity of conducting investigations on jam floods has been often pointedout in Polish literature (Kolberg 1861; Słowikowski 1881. 1892; Puciata 1894; Walewander1932; Kobendzina 1954; Mikulski 1955, 1957, 1962; Wokroj 1954; Tyszka1954; Pasławski 1970), as well as in papers concerning ice phenomena (Gołek 1957;Zubrzycki 1927). Only disastrous jam floods have been adopted as the scale ofthe jam. The floods caused by ice jam overflow the populated areas in the rivervalley and bring forth much damage. The main aim of the present paper was topresent a historical record of the greatest water level rises due to ice jams onthe Lower Vistula, the regions in which they formed and their main causes.

Marek Grześ, Institute of Geography and Spatial Organization Polish Academy of Sciences, Kopernika 19, 87-100 Toruń, Poland