Advances in Water Treatment and Enviromental Management

24 WATER TREATMENTTable 1. Classification of Ambient Waters* All values in mg/1. Coliforms in MPN/100 mlwinter. The total length of the river course covered in this part of the study isapproximately 94 kilometers (see Fig.l).River Classification and Ambient Water Quality StandardsAmbient water quality classification is given in Table 1. Classes I, II-a and II-brespectively correspond to categories A 1, A 2and A 3as defined by the Council ofEuropean Communities (Luxemburg, June 1965).Pollution SourcesTwo major towns— a ak and Gornji Milanovac are situated in this area. Both areimportant industrial centres. The pollution loads from these towns, municipal andindustrial, expected in 1990 are listed in Table 2. These data are based partly onextensive field measurements of waste water discharges in a twelwe-month periodin 1978–1979 and partly upon regional development plans and enquiries in industry.Non-point sources of pollution were neglected as low flow condition are simulated.MODEL CALIBRATIONDescription of the Program STEKARThe river system is divided in to) segments with homogeneous characteristics andrepresented as nodes in the mathematical model. For each node, the following dataare collected: length, average depth, surface area, volume. The nodes are linked bychannels, each one being characterized by: cross-section area, depth, velocity offlow, bottom slope. The data on ambient water quality, weather conditions and