University of Sistan and Baluchestan Journal of Hydrosciences and Environment 2345-5608 5 10 2021 12 01 Water Quality Management by Means of Assimilative Capacity Considering Allowable Concentration and Affected Distance 20 26 7608 10.22111/jhe.2023.45322.1087 EN Hashemi Monfared Seyed Arman University of Sistan and Baluchestan Mohsen Dehghani Darmian University of Sistan and Baluchestan, Zahedan, Iran. Bahareh Pirzadeh Faculty of engineering , University of Sistan and Baluchestan Mehdi Azhdary Moghaddam University of Sistan and Baluchestan Journal Article 2023 04 11 Industrial and urban development, Population growth and settlement are common cause of increased pollution. Pollutants are in many instances discharged untreated to rivers due to lack of adequate treatment facilities and high treatment cost. This paper considers assimilative capacity as an important water quality index when the river point source pollution is controllable. The simulation of pollution transport in the river and calculation of assimilation capacity is based on the mathematical equations of pollution propagation with no turbulent flow. The proposed procedure for water quality protection is applied in a hypothetical case study and the obtained results are expressed. The results demonstrate that the river flow variation can modify the assimilation capacity up to 97%. https://jhe.usb.ac.ir/article_7608_73f958ee5a4ddda03fbd698ffc3e8bae.pdf