Hidrológiai Közlöny, 2016 (96. évfolyam)
2016 / 3. szám - HISTORICAL SNAPSHOT - Kerekes-Steindl Zsuzsanna: Water quality protection in Hungary - policy and status
44 Hungarian Journal of Hydrology Vol. 96. No. 3. 2016. The nutrient emission loads polluting surface waters originate approx. 40% from point and 60% from diffuse pollution sources in Hungary. The high amount of organic and nutrient compounds can cause deterioration of the water quality not only in the Hungarian waters, but also effect the downstream Danube sections. The total amount of these pollutants, originating from the entire (international) river basin (including Hungary) significantly contributes to the eutrophication status of the Danube Delta in Romania and to the deterioration of the water quality of the Black Sea, as well. For the estimation of the spatial patterns of nutrient pollution sources in the basin contributing to the total emissions and assessment of different pathways of the emissions into waters, the MONERIS model was applied for the entire basin using the current hydrological conditions (2009-2012) during the preparation of the international level Danube river basin management plan in 2015. (Fig. 1. and Fig. 2.) The total nitrogen (TN) emission load was estimated as 605.000 tons per year, and the total phosphorous (TP) as 38,500 tons per year. 5 % of the overall TN and 7 % of the TP emission originated from the Hungarian territory by the model estimation. (The whole country belongs to the Danube river basin, and shares 11.6 % of the total river basin area. Consequently the country’s nutrient emission load is lower than its territorial ration.) Figure 1. Share of pathways of total nitrogen (TN) and total phosphorous (TP) emissions in the whole Danube Basin (2009-2012 reference period) (Source: 1CPDR 2015) Figure 2. Share of sources of total nitrogen (TN) and total phosphorous (TP) emissions in the whole Danube Basin (2009-2012 reference period) (Source: ICPDR 2015) The inadequately treated industrial wastewater can discharge different contaminants into the receiving waters, especially if the best available techniques (BAT) is not applied. Municipal wastewaters often contain different chemical pollutants also, even after treatment. Chemical pollutants can originate from different diffuse sources as well, e.g. from the excessive or improper use of agricultural chemicals. The so called „historically” polluted sites cause local quality problem, mainly in the case when the remediation measures are not in place or not effective enough. These chemicals can endanger the water ecosystems, and can be harmful for human health as well. In some parts of Hungary (mainly in the Tisza River Basin) the higher level of geological background contamination of the soil and rocks can pollute the waters as well, primarily with different types of heavy metals. In these cases concentration of some quality parameters in the groundwaters can exceed the drinking water limit values and the water can be used only for drinking water supply after adequate treatment. The accidental (havaria) pollution cases coming from upstream catchments areas are also frequently associated with dangerous substances pollutions. The hydromorphological alterations, which modify the natural water beds, the water balance, the runoff conditions of the rivers and lakes can significantly affect the living condition of the aquatic ecosystems and the quality status of waters. Most of the Hungarian waters are affected by previous interventions, which significantly
