Flood risk assessment in the seashore-related river basins of Lithuania

Abstract

Intensive summer rain showers in 2005 and 2007 caused flood in most rivers of Lithuania. The showers were similar to spring or late-winter ones, but quicker in appearance. The majority of problems occurred in the basins of the Akmena-Dane and Minija Rivers that are adjacent to the seashore. Occurrence of large runoff volumes resulted to the extremely high river level. Spring floods caused by heavy rain or thawing snow are possible to be predicted in many cases avoiding any possible dangerous consequences at the same time. Being the reason of natural calamities rapid river level raise during unexpected high flood can result to the breaching dams. It is especially evident when high sea level in the Baltic Sea caused deep cyclones resulted to additional surplus of rivel level that exceeded extreme gauge readings. The current reasearch focuses on the consequences of past present and future possible dam breaching in the Akmena-Dane River basin. Modelling of possible impact of other dam-protected reservoirs is also analyzed in the vicinity of some other processes, including extremely high river level raises, caused by storm water surges from the sea or coastal lagoon.