Theme-I-5-Assessment of groundwater quality for irrigation purpose in Amritsar district, Punjab (India)

Abstract

Amritsar district is one of major intensive agriculture districts of Punjab, producing food grains to the Indian nation. The district is covering about 5058 sq.km area drained by two perennial rivers Ravi and Beas. Irrigation water requirements are dependent on shallow/deeper tube wells in addition to the existing surface water irrigation facility from canals. Dwindling flows in canal supplies has lead to rapid decline of the groundwater levels about 50-60 crn/yr during last two decades. Incriminate use of agrochemicals tend to increase salinity and sodicity of the soils in this district. Main objective of the present study is to evaluate the groundwater suitability for irrigation and to classify it according to amount of salts present. Groundwater samples and has been collected at 51 observation wells and physiochemical (pH, EC, Ca", Mg"' Na`, lc-, HCO3', C1, SO4-7, F- and NO3-) parameters were analyzed during last two hydrologic cycles. Based on these analyses, Sodium absorption Ration (SAR), % Sodium, and Residual Sodium carbonate (RSC) were calculated for one hydrological cycle of the year 2007.

The groundwater quality analyses revealed that most of the samples were within the lower alkalinity limit (pH 7.14-8.10). The electrical conductivity of the samples ranged from 434 to 2499 µs/cm. Other parameters like sodium adsorption ratio, SAR (0.76-10.83), RSC (0-5-7.51), %Na (19.71-84.64) were found above the permissible limit in the most of the samples. Wilcox diagram of pre-monsoon indicated that 2 samples fall in high saline and high sodium hazard, 12 samples falling in Medium saline and high sodium hazard, 6 samples are found in medium saline and medium sodium hazard, 31 samples falls in High saline and low sodium hazard. The groundwater quality analyses further indicated that almost all samples exhibits increasing trend of salinity during post monsoon period.