Survey of this year’s floods

Spring floods in Dviete floodplain this year started slightly later than usual, still the highest level of water corresponded to mean value of many years. Rising of water level in river Dviete near Bebrene began on March 12 and continued till April 15. Rising of water level was most rapid (25-28 cm daily) from April 1 till April 6, when ice-blocks formed in Daugava at river Berezovka mouth. Totally water level in Dviete floodplain near Bebrene rose by 3.38 m and reached the level of height 90.47 m above sea level, not reaching the highest flood level of the last year by about 1 m.

To compare, in Daugava bear Vaikuļāni (Līksna), where the nearest hydrological observation point of the Latvian Environment, Geology and Meteorology Centre is located, water level during the same time period rose by 5.23 m and on April 15 reached the level of height 91.04 m above sea level, exceeding mean  perennial flood level there by about 0.4 m. Besides, maximal water level of the current year in Daugava near Vaikuļāni was observed four days earlier than in average (observations from many years).

As usual, also in the current year in Dviete floodplain during its filling phase there was a strong current from the side of river Daugava, reaching Bebrene surroundings on April 11 and continued to flow upstream Dviete valley three days more. When the highest flood level was reached, water current to the direction of Daugava began again. At the middle of April 2011, spring flood water had filled Dviete floodplain almost in all it's length until it's end near Kaldabruņa (image).

Currently water level in Dviete floodplain has significantly decreased, still near Bebrene it is 0.5 m higher than at the end of the winter. Lowest sites at the banks of streams and lakes are still under the water, thus spring floods in Dviete floodplain still continue.

09.05.2011.
Dāvis Gruberts, Ph.D.,
Daugavpils University, Chair of Geografy

Daugava river basin from the space 13.04.2011. (bluish-white – snow in highlands, blue – ice in lakes, dark blue – flood water)