Assessment of  Water Quality of Telvar River Using Hydrochemical Diagrams

Mousavian, Sahar; Vafakhah, Mehdi; Moosavi, Vahid

doi:10.22059/ije.2026.408169.1899

Assessment of Water Quality of Telvar River Using Hydrochemical Diagrams

Articles in Press

Document Type : Research Article

Authors

Department of Watershed Management Engineering, Faculty of Natural Resources and Marine Sciences, Tarbiat Modares University, Noor 46414-356, Iran

10.22059/ije.2026.408169.1899

Abstract

Objective: This study investigates the chemical quality of surface waters at three stations (Mehrabad, Chamshur-Shadiabad, and Chamshur-Delbaran) in the Telvar River watershed, to identify the dominant hydrochemical processes and assess the suitability of these waters for irrigation.

Method: Major ions (Na⁺, K⁺, Ca²⁺, Mg²⁺, Cl⁻, SO₄²⁻, HCO₃⁻, CO₃²⁻), along with EC, TDS, and pH, were analyzed. Hydrochemical diagrams including Piper, Durov, Gibbs, Stiff, and USSL, were used for data interpretation.

Results: The results showed a clear dominance of Na⁺+K⁺ cations and Cl⁻/SO₄²⁻ anions, while Ca²⁺ and HCO₃⁻ were limited to specific locations. Piper and Durov diagrams confirmed the evolution from Ca-HCO₃ to Na-Cl/Na-SO₄ water types. The Gibbs diagram indicated evaporation and mineral dissolution as the dominant controlling mechanisms. The USSL diagram placed most samples in high salinity (C3-C4) and high sodium (S2-S3) classes. Agricultural indices revealed high risks of sodicity and reduced soil permeability.

Conclusions: Water chemistry in this semi-arid watershed is primarily controlled by evaporation, ion exchange, and dissolution of evaporite and carbonate minerals. Direct use of these waters for irrigation is limited without proper soil management (e.g., leaching, gypsum application). Sustainable water resource management is essential to prevent soil salinization and sodicity.

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