Investigating the seasonal changes in the chemical and microbial quality of water in the transmission channel of the Faculty of Agriculture and Natural Resources of Tehran University

Surface waters are more exposed to pollution and quality reduction than other sources. In the current research, the seasonal changes of the water transfer channel of the University of Tehran School of Agriculture and Natural Resources have been investigated and analyzed. In this research, water samples were taken from the studied water transmission channel during different seasons of the year from three places along the channel using glass containers, water samples were prepared and transported to the laboratory. The results show that the total amount of soluble substances in water varies from about 27 mg/litr in winter to 375 milligrams per liter in summer. In autumn and winter, canal water is in class C1, which means low salinity, and in spring and summer, it is in class C2, medium salinity. Therefore, it will not create a problem for watering crops. Canal water is evaluated in medium condition in terms of acidity. The amount of oxygen index required for oxidation of canal water ranges from 3.5 mg/100 ml to 5.4 mg/100 ml. The COD value of canal water ranges from 25 mg/100 ml in winter to 47 mg/100 ml . Results of water samples showed that nitrification occurs in the canal. The amount of nitrate varies from 1.08 to 1.6 mg/liter in different seasons.The amount of coliform varies from 770 units per 100 ml in winter to about 1100 units per 100 ml in summer, and this is consistent with the change trend of other quality indicators of canal water.