The Effects of Trout Farm Effluents on the Water Quality Parameters of Haraz River

The effects of trout farm effluents on the water quality parameters and self-purification in the Haraz river were investigated. In this study, four trout farms and ten stations were selected. Physiochemical characteristics and nutrients of water, including water temperature, dissolved oxygen (DO), biological oxygen demand (BOD5), total hardness, pH, total dissolved solids (TDS), total suspended solids (TSS), turbidity, electrical conductivity (EC), phosphate, ammonium, nitrate and nitrite were monitored, one every two months annually. The resultsshowed that the average of these parameters were within a range between 8.9-11.7 oC for temperature, 8.7-11.3 mg/lit for DO,2.95-5.9 mg/lit for BOD5, 7.4-7.9 for pH, 160-245 mg/lit for total hardness, 209-247 mg/lit for TDS, 62-156 mg/lit for TSS, 21.2-76 NTU for turbidity, 389-491 μm/cm for EC, 0.014-0.115 mg/lit for PO4, 0.014-0.783 mg/lit for NH4, 0.74-1.49 mg/lit for NO3 and 0.003-0.021 mg/lit for NO2, respectively. All the parameters showed fluctuations at different stations, and some of them such as DO, TSS, NH4 and turbidity had been shown to differ significantly between stations. These results were due to the effects of trout farms and of the self-purification of river. Meanwhile, all the parameters showed changes in different seasons that were due to fluctuations of environmental conditions and activity rates of the farms.