Seasonal changes in the water quality of Sardab river: dual perspectives of the Iran Water Quality Index for Surface Water Resources – Conventional Parameters (IRWQIsc) and the National Sanitation Foundation Water Quality Index (NSFWQI)

Document Type : Research Paper


Department of Civil Engineering, Faculty of Civil Engineering and Environment, University of Shahid Beheshti, Tehran, Iran.



The quality of river water is of great importance due to the limited availability of freshwater resources and the increased demand for water in the drinking water, agriculture, and other sectors. Rivers are one of the sources of this water supply, which are exposed to indiscriminate discharge of industrial, agricultural and human wastewater without proper environmental considerations.The study area in this research is the Sardabrud River located in Mazandaran province. The required data for conducting the research were collected from three stations along the river throughout a hydrological year and analyzed. In this study, the Iranian River Water Quality Index for surface waters (IRWQIsc) and the National Sanitation Foundation Water Quality Index (NSFWQI) were used to evaluate the river water quality. Based on the results, the values of the IRWQIsc index varied between 92.12-30.42 and the NSFWQI index between 92.35-48.075, indicating very good quality in spring and bad quality in winter for IRWQIsc, and excellent quality in spring and bad quality in summer for the NSFWQI, respectively.. Among the most important factors polluting the water of this river along its course are the discharge of agricultural and human sewage into the middle and downstream reaches, land use changes, and climate changes - which have caused a decrease in water quality along the river's path.Using the obtained results and current understanding, measures can be taken to prevent these polluting sources from entering the river to improve its water quality.


Main Subjects

  1. Aghaee, M., Heshmatpour, A., G. Mahmoodlu, M., & Seyedian, S. M. (2020). Investigation of Water Quality of Chehelchay River Using IRWQIsc Index. Journal of Environmental Science and Technology, 22(5), 153-166. (in Persian)
  2. Aghajanloo, K., Hajizadeh, E., & Ariaeezadeh, S. (2022). Evaluation of Karun River Water Quality Based on IRWQI and WAWQI Indicators in Molasani and Ahvaz Stations. Iranian Journal of Soil and Water Research, 53(2), 367-380. (in Persian)
  3. Chowdhary, P., Bharagava, R. N., Mishra, S., & Khan, N. (2020). Role of Industries in Water Scarcity and Its Adverse Effects on Environment and Human Health. In Environmental Concerns and Sustainable Development. Air, Water and Energy Resources,1, 235-256.
  4. Ebraheim, G., Zonoozi, M. H., & Saeedi, M. (2020). A comparative study on the performance of NSFWQIm and IRWQIsc in water quality assessment of Sefidroud River in northern Iran. Environmental Monitoring and Assessment, 192(11).
  5. Khalili, R., Montaseri, H., & Motaghi, H. (2021). Evaluation of water quality in the Chalus River using the statistical analysis and water quality index (WQI). Water and Soil Management and Modelling, 1(3), 38-52. (in Persian)
  6. Khoshravesh, M., Sarjaz, M. R., Tehrani, E. N., & Koulaian, A. (2015). The Impacts of Urbanization and Impervious Surfaces on Runoff of Sardaabrud Basin, Kalardasht, using HEC-HMS Rainfall-Runoff Model. Iranian Journal of Irrigation & Drainage, 9(1), 209-220. (in Persian)
  7. Larijani, S., Hossein, B., Kavian, A., & Ziaei, A. N. (2022). Sensitivity assessment of two water quality models NSFWQI and IRWQISC in Haraz River. Iranian Journal of Irrigation & Drainage, 16(4), 816-830. (in Persian)
  8. Mazlomi Mochani, M., Hatami, A., Moridi, A., & Khalili, R. (2023). Sensitivity assessment of the National Sanitation Foundation Water Quality Index (NSFWQI) and IRan Water Quality Index for Surface Water Resources (IRWQIsc) on the water quality of the Neka River. Water and Irrigation Management, 13(3), 581-592. (in Persian)
  9. Mirzaei, M., & Solgi, E. (2016). Evaluation of surface water quality using NSFWQI index and pollution risk assessment using WRASTIC index in 2015, Archives of Hygiene Sciences, 5(4), 264-277.
  10. Rezaeiarshad, N., Rafiee, M., Sayyadi, M., & Eslami, A. (2022). Spatiotemporal Analysis and Health Risk Assessment of Nitrate in Kan River Basin, Tehran: Application of IRWQI and Monte Carlo Simulation. Journal of Environmental Health and Sustainable Development, 7(4), 1797-1815.
  11. Samadi, J. (2016). Survey of Spatial-Temporal Impact of Quantitative and Qualitative of Land Use Wastewaters on Choghakhor Wetland Pollution Using IRWQI Index and Statistical Methods View project. Iran-Water Resources Research, 159-171 (in Persian)
  12. Tiyasha, Tung, T. M., & Yaseen, Z. M. (2020). A survey on river water quality modelling using artificial intelligence models: 2000-2020,  Journal of Hydrology, 585, 124670
  13. Al-Sudani, I.M., Al-Razzaq, H.T.A., Khraibet, A.C., & Mohammed, H.J. (2022).  Impacts of untreated sewage effluent on Tigris river water quality using (NSF-WQI) index. Journal of Genetic and Environmental Resources Conservation, 10(1), 7-13.
  14. Valadan Zouj, M. J., Rezaei, Y., Vaziri, F., & Mobasheri, M. R. (2009). Investigation on Alam Chal Glacier Using Satellite Images. Scientific Quarterly Journal of Geosciences, 18(70), 2-13. (in Persian)