ABSTRACT
This study investigated seasonal variation of groundwater quality indices in irrigation watershed of Hadejia located along Hadejia
River Basin of Jigawa State. Six transects, oriented perpendicular to the river channel were established within 1 km2
in each site.
Three tube wells were sampled and positioned along each transect at regular intervals, making a total of 18 wells. Six irrigation
water quality indices (EC, SAR, MH, PI, %Na and KR) were computed and results were presented using ORIGIN software.
Results showed that with the exception of EC and RSC which put the water under doubtful to unsuitable classes, all other indices
put the water in the excellent to good classes for irrigation. However, the results also show that the suitability of the water is
lower in the dry season than in the rainy season. This is because the dry season was found to have more concentration of these
parameters than in the rainy season, suggesting the impact of evaporation which causes these parameters to precipitate in the
groundwater during the dry season. Groundwater samples in the area are suitable only for tolerant and semi-tolerant crops in all
the seasons of the year. Thus, highly sensitive crops to salinity such as onion and carrot may be affected by the present salinity
condition of the water. Monitoring the suitability of groundwater quality indices is recommended in order to detect changes that
require modifications in the management options for proper planning.