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silted-up, and also the shallow reservoirs on mountainous, upland and lowland rivers, in providing reduced rates of load to the Vistula, is minimal.

2. Proposal for the correct location of new dams. The best solution to the problem of the silting of new reservoirs, as outlined above, must take into account the following:

—    firstly, the deep reservoirs in the middle stretches of the large Carpathian rivers should be completed to achieve minimum supplies of river load from the Carpathians to the Vistula,

—    secondly, if this programme is finished, a new reservoir on the Vistula should be built downstream from Cracow. If dredging practices in the reservoirs located in the Upper Vistula start at the beginning of reservoir operation, the siltation of the reservoirs located downstream will be very limited.

Fig. 11. Estimated total supply of the suspended load to the Vistula by the Carpathian tributaries (A) and supply of the load to the Baltic Sea by the river (B) in 1900, 1968 and 1996

a — supply of suspended load to the river and the Baltic Sea when planned deep reservoirs on the Carpathian rivers are completed, b — supply of suspended load by the Vistula to the Baltic Sea when the above reservoirs and planned ones on the whole course of the river are completed

3. Estimated changes in suspended load transportation rates by the Vistula as a result ofman’s impact on fluuialprocesses. Prognosis. Up to the beginning of the 20th century the suspended load transportation rates of the Vistula increased in the previous millennium morę than 10-fold (Maruszczak 1988). Due to reseryoir siltation, the sum of suspended load supply to the Upper Yistula by the Carpathian tributaries has decreased between the 1930s-1950s