Freshwater - State and impacts (Former Yugoslav Republic of Macedonia)

The main area of higher biological oxygen demand (BOD) concentration is in the catchment of Vardar river, the main river basin in the country.  

A trend of rising BOD 5 and ammonium concentrations (Fig.4 and 5) was tracked in the rivers in the Republic of Macedonia at certain measuring points in the period 1988-2008. Eutrophic status with high BOD was particularly recorded in two rivers: Crna Reka and Vardar. These results could reflect the status of inefficient treatment of urban and industrial wastewaters in the country, as well as the inadequate protection of river basins.

Among the main reasons for the poor river water quality are also solid waste and wastewater discharge from almost all settlements.

The same applies to the concentration of nitrates and orthophosphates which are still at a high level with no substantial changes.

On the other hand, there has been well-documented improvement in the quality of bathing waters and also an improvement in drinking water quality.

Evaluation of the status  and description of the trends

During 1988-2006, the rising trend in BOD 5 and concentrations of ammonium in rivers were tracked at certain measuring points in the Former Yugoslav Republic of Macedonia. In the Crna Reka and Vardar, eutrophic water status with a high BOD value was recorded. These results could reflect the inefficient treatment of urban and industrial wastewaters, as well as inadequate protection of river basins. The annual mean concentrations of nitrates and orthophosphates were relatively stable during the analysed period, 1988-2006. Increased annual mean values of these were, however, recorded at certain points in the River Vardar.

Throughout the observed period, the Ohrid lake sustained its oligotrophic nature with relatively stable concentrations of phosphorus and nitrates with annual mean concentrations below 0.015 mg/l and 0.55 mg/l respectively. Unfortunately, more recently the situation has been getting worse and is expected to show in the level of eutrophication. Significantly higher concentrations were found in the waters of the Prespa lake, where the content of organic matter has reached a high level, increasing the risk of eutrophication.