Advances in Water Treatment and Enviromental Management

NON-POINT DISCHARGES FROM URBAN AREAS 227Fig 2 Influence of urban NP discharge from different numbers of inhabitants onBOD and DO in the stream.organics oxidation rate constant day -1 , respectively; A-bottom sediments oxygenconsumption rate mg/m 2 per day; Fg-bottom sediments area, m 2 ; V-volume of NPand reservoir water rnixutre, m 3 .The minimal DO concentration will occur after time determined by formula(7Substituting (7) into (6),value.can be found and compared with the normative DOField investigations conducted in the city of Kharkov elucidated features of oxygenconsumption by the solid phase in the discharge (Proma, 1983) and by bottomsediments originating primarily from NP discharge (Khvat, 1983).Computer calculations, performed on the basis of (6) and (7), evaluated theinfluence of NP discharge on DO regime in reservoirs and sluggish streams in thewide range of volumes of NP and river water in the town segments of the waterbody, as well as an initial oxygen deficit and average depths of the reservoir. Fielddata of the bottom sediments oxidation rates from 0.34 to 4 g/m 2 per day wereused in calculations.The analysis applied to streams and reservoirs allowed definition of water bodiesneedling urgent protection against pollution from urban NP discharges. Such are