To avoid this, from the outset of the flooding, the Institute of Public Health of Belgrade City increased the drinking water monitoring sequence and installed additional treatment by activated carbon, in order to monitor any flood-related impact. At the same time, what is now the Ministry of Agriculture and Environmental Protection, carried out monitoring of the surface water of the Drina and Sava Rivers at selected sites upstream of the water source area of Belgrade, to control the main potential threats, leakage and “washing-out” of contaminants in the flooded area draining to the rivers, with special focus on industrial sites, the high concentration of pesticides from agricultural land, and sanitary and septic wastes also entering the water system from downstream. In addition, this Law stresses the importance of the development of water transport, as well as the ports and harbours of Serbia. Vessels are prohibited from the discharge and leakage into inland waters of harmful objects or substances, including oil and oil derivatives, which may cause pollution of inland waters or create obstacles and dangers to navigation.