Hidrológiai Közlöny 1977 (57. évfolyam)
1. szám - Mátrai István: A magyar vízügyi nagylétesítmények és a Vízminőségszabályozási Mintaterületek Project
18 Hidrológiai Közlöny 1977. 1. sz. Mátrai István: A magyar vízügyi nagylétesítmények Fig. 3. Sources of pollution in the Sajó Valley (1) National boundary, (2) Major effluent discharges, (3) Minor polluting discharges, (4) Monitoring stations 3. ábra. Sajóvölgyi szennyezőforrások (ÍJ: határ; (2): nagyobb szennyvízbevezetések; (3): kisebb szennyvízbevezetések; (4): monitorállomások modelling. In this respect Hungary has received valuable assistance under the Project HUN/PIPOOl "Pilot Zones for Water Quality Management" the contract for which was signed in May, 1972 with the United Nations Development Program (UNDP) and the World Health Organization (WHO). Under the 5 years period the Project is concerned with the two pilot zones designated on two streams, namely the Hungarian section of the Sajó River and the Hungarian —Czechoslovakian Danube section upstream of Budapest. There are substantial differences between the two pilot zones and thus also between the resulting problems. In the first pilot zone, the Hungarian section of the Sajó River (Fig. 3) — the river enters Hungary in a highly polluted condition, the streamflow varies between wide limits, the lowest value being 2.5 cu.m/sec, —- the Sajó valley is highly industrialized already, yet considerable further development is envisaged, — the water resources are very limited, virtually no free resources being available, — water quality control in the Sajó River, discharging above the Kisköre reservoir into the Tisza River is of great importance for the water supplies in the latter. The situation on the Danube differs radically from that on the Sajó River: — the streamflow is much more uniform the lowest rate is round 600 cu . m/sec, — at the entrance to the country the quality of Danube water is better, of category II, but contains considerable background pollution, — the section in question forms the national boundary over much of its length, so that the investigations were necessarily restricted to the discharges on the right-hand bank. Over this section the volume of waste waters discharged by communities and industries is relatively smaller. Consequent from the conditions outlined in the foregoing, the Project resulted in specific; recommendations concerning the quality control measures, whereas in the case of the Danube a descriptive model has been formulated with recommendations concerning pollution abatement. The proper implementation of a quality control program on the Sajó River is likely to create favourable conditions also for using the supplies in the Tisza River. The Sajó discharges into the backwater reach above the Kisköre—the Tisza II —Barrage. The channel impoundment reservoir of 400 million m 3 volume will augment the flow in the Tisza River at low water periods, especially in the July —August period. This lends added importance to further investigations on protecting the quality of the stored water as regards the limit values of the various components. Major installations of the power- and chemical industries have already settled along the Kisköre impoundment and further development thereof is under way. The reservoir feeds irrigation canals supplying water to lands of 300 thousand hectares order of magnitude. The potential pollution hazard is expected to increase materially with the develop-
