3.3. Quality of surface waters
The monitoring of the quality of the surface waters is being done by the Hydro Meteorological
administration of the Republic of Macedonia. The monitoring comprises of 20 measuring stations located
on the rivers, lakes and accumulations [Fig. 5]. The classification of the surface waters is performed in
accordance with the bylaws: Regulation on water classification (Official Gazette of RM, No.18/99) and a
Regulation for categorization of watercourses, lakes, accumulations and underground waters (Official
Gazette of RM, No.18/99). According to this classification, today there are five classes of waters, where
the quality of the first (I) class is the best and the quality of the fifth (V) class is the worst [3].
The pollution of the surface water flows in the Republic of Macedonia is being monitored through
BOD5, the content of total ammonium, nitrates and nitrites in the rivers. The analysis will be taking into