Assessment of groundwater quality for irrigation purpose, district Nainital, Uttarakhand, India

Abstract

The ground water quality of District Nainital has been assessed to see the suitability of ground water for drinking and irrigation applications. This is a two part series paper. In an earlier paper, we have examined the suitability of ground water for drinking purpose. This paper examines the suitability of ground water for irrigation applications. Forty ground water samples (including 28 spring samples) were collected during pre- and post-monsoon seasons and analysed for various water quality characteristics. The suitability of ground water for irrigation purpose has been evaluated based on salinity, Sodium Adsorption Ration (SAR), Residual Sodium Carbonate (RSC) and boron content. In general the ground water of District Nainital is safe for irrigation purpose. According to U.S. Salinity Laboratory classification of irrigation water, about 90 % of the samples fall under water type C2-S1, such water can be safely used if a moderate amount of leaching occurs and plants with moderate salt tolerance can be grown in most cases without special practices for salinity control. About 10% samples fall under water type C3-S1, such water cannot be used on soils with restricted drainage. Even with adequate drainage special management for salinity control may be required and plants with good tolerance should be selected.