This study analyzed and expressed the hydrochemical characterization and irrigation suitability of the Karmanasha River water, Lalitpur Nepal.
Hydrochemistry of the Karmanasha River basically indicates slightly alkaline nature with pH value of 8.07. HCO3 - is the dominant anion and Ca2+ is the
dominant cation in the sampling stations of the river. The mean EC and TDS values indicated that the river has medium salinity which directly affected by the various anthropogenic activities. The grand mean values of the major ions follow the order Ca2+>Mg2+ >Na+>K+for cations and HCO3 ->Cl- >NO3 -
for anions. The results revealed that the water is safe for irrigation purposes based on EC, Na%, SAR, KR, MAR, and CROSS. Wilcox diagram also revealed that the river is safe for irrigation purposes and fall on the major two categories (C1S1 and C2S1). However, the river water of the Karmanasha is not appropriate for the drinking purposes mainly due to the high values of BOD and COD. The Water Quality Index (WQI) is also indicted that the water is not fit for the drinking purposes. This study provides the baseline information about the WQI and suitability of irrigation water quality, and further studies are recommended at spatiotemporal levels for getting the in-depth insights about the ecological health of the river.