The trends of changes in the maximum and minimum annual discharges, taking place in the years 1984–2000, were analysed for two catchments differing in the land-use pattern: a forest catchment of the Czartusowa river up to the „Szklarnia” gauging station, and an agricultural catchment of the Branew river up to the „Flisy” gauging station. The maximum discharges (WQ), regardless of the character of the catchment, showed on increasing trend, while the minimum discharges (NQ) tended to decrease in the forest catchment devoid of springs and to increase in the agricultural catchment supplied with water from springs. It was found that in the agricultural catchment droughts last longer, especially in the summer half-year, but their frequency is lower than in the forest catchment. Floods occur more frequently in the agricultural catchment and their number, as in the forest catchment, is twice as large in the winter than in the summer half-year.

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