Groundwater Quality Assessment for Irrigation Uses in Upper Thirumanimuthar Sub Basin, Cauvery River, Tamil Nadu, India (original) (raw)

2010, Journal of Applied Geochemistry

In the present paper, an attempt has been made to work-out the groundwater suitability for irrigation representing froma totalareaof about340.46Km2in upperThirumanimuthar sub-basin,CauveryRiver.51 groundwatersamples were collected during pre monsoon (May) 2007 and analysed for major cations and anions. The irrigational parameters like; EC, Kelley's ratio, SAR values, Mg-hazards, HCO) and RSC have been worked out to know the suitability of the groundwater for irrigational purpose. The study has shown salinity of groundwater under "increasing problem" zone at majority of sites. The groundwater falls under class-I (Doneen's) good to permissible (Wilcox) zone indicating that it is good for irrigation use as per the classifications of Doneen' s Permeability Index and Wilcox diagram interpretation. It is found that the SAR values when plotted in the USSL Staff diagram belong to C)-S, (58.82) and C2-S, (1.96%) classes indicating that the groundwater could be used for all types of crops on soils of medium to high permeability. However, the concentration of bicarbonate was in significant amount showing 56.86% of sites under "increasing problem" and the 43.14% sites under "Severe Problem" zones. The residual sodium carbonatevalues of the all groundwater samples are within safe category except two samples. In the present study, it is evident that high salinity of groundwater persists at majority of the sites. Hence, for high to very high salinity of groundwater, soil must be permissible with adequate drainage facilities to ensure satisfactory crop growth.