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Measured And Modelled Water Transport In The Odra Estuary 
For The Odra Flood Period July/August 1997 
W. Rosenthal 
GKSS Forschungszentmm 
Max-Planck-Strasse 
21504 Geesthacht 
Abstract 
The Szczecin lagoon is the interface between the Odra river and the Baltic Sea. The connecti 
on to the Baltic Sea is via the three exits of rivers Swina (about 70 % of the total water trans 
port), Dziwna and Peenestrom. 
In recent years knowledge on impact of the lagoon for water quality and the transformation of 
dissolved and suspended matter in the Odra water has improved considerably due to several 
international projects in the area (GOAP, TRUMP, ODER, ...). The present knowledge on 
water transport through the Szczecin lagoon is restricted to summer situations with low to 
moderate fluxes from upper Odra river. A difficulty in the investigations are estimates for the 
processes in extreme events due to the lack of data. For instance in winter times the lagoon is 
normally ice covered and therefore the installation of measuring platforms is difficult. The 
period of the spring highwater of the Odra river is for instance not well covered with co 
herently measured data. Therefore the highwater period in July/August 1997 of the Odra river 
provided for the scientific community an important opportunity to learn about the transport 
and transformation processes in the Szczecin lagoon and to determine the water transport into 
the Baltic Sea for the period of such an extreme event. 
In the western part of the lagoon two automatic stations have been set up that reported hydro- 
graphic and meteorological data directly to the GKSS research institute. It also reached other 
interested parties online by internet. A pontoon was moored in the western lagoon that was 
used for taking water samples and for radar and video observations of surface waves and 
windfield patterns on the water surface. In the Polish part of the lagoon (Zalew Wielki) the 
research vessel Ludwig Prandtl of GKSS was given permission by Polish administration to 
measure hydrographic and meteorological parameters. The main profiles were run across the 
entrance of the Odra river into the lagoon near to Trzebiez and in the Swina river near to Ka- 
sibor. 
The main transports took place in the Zalew Wielki and could be documented by ship profiles 
with measurements of currents, water quality parameters and of primary production. An ob 
vious feature have been the strong seiges that were measured by the current meters. The sei- 
ges will produce a considerable error in the estimates of the water fluxes since current 
amplitudes of .25 m/s were meaured at one of the stations. 
A not yet completely answered question is the quantitative water transport in the different 
places of measurement along the lower part of Odra river and through the Szczecin lagoon 
and the straits to the Baltic Sea. The different measurements for the extreme fluxes are not 
always mutually consistent. 
In the lagoon itself current patterns form, that are important for the flushing and retention 
capabilities. The current patterns were estimated by measuring with automatic stations the