Based on the monthly measurements performed from April to September 2005 in the layers 0-10, 20-30, 40-50, 65-75 and 90-100 cm of four characteristic soil profiles, the study assessed the soil moisture conditions in the left-bank part of the Odra river valley upstream of the Malczyce dam under construction. The changes in water reserves were analysed in relation to precipitation, depth of groundwater table, and stage of water in the Odra river. The basic physical properties of soils were determined and the water retention curves were drawn, then the moisture ranges corresponding to the characteristic moisture conditions were established. The precipitation of the study period was close to normal. Because of the quite deep groundwater table near the soil profiles (deeper than 1.5 m in all measuring points, deeper than 4 m in part of the area) the upper soil layers studied were supplied only from precipitation and their moisture did not depend on the level of ground waters. Profiles No. 7 and 10 had more favourable moisture conditions: for most of the study period, the water reserves in the layer 0-50 cm ranged between the field water capacity and the drought water capacity. The moisture conditions of profiles No. 8 and 9 were worse; in the former, the total water reserves both in 0-50 and 0-100 cm layer were most often lower than the value corresponding with the wilting point.

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