The water level on the Oder river flowing through the Polish city of Wrocław peaked overnight and is expected to stay high for some time, the metrological authority said on Thursday morning. The water level at the Trestno measuring station just outside the city of 630,000 people was stable at 6.31 metres. Usually the water is a little over 3 metres high. The current flood wave is significantly lower than during the major Oder river flood of 1997, when the water level reached 7.24 metres in the city. But Prime Minister Donald Tusk warned against underestimating the severity of the situation, sa…