Quality of groundwater for irrigation in tehsil Taxila of district RawalpindI, Punjab

A study was undertaken to categorize suitability of groundwater for irrigation purpose in Taxila area of Rawalpindi district. A total of 628 water samples were collected from nine union councils in Taxila, analyzed and categorized according to the suitability criteria of water quality evaluation. Sixty six percent water samples were fit, 21 % were marginally fit and 13 % were found unfit for irrigation purposes. In majority of the union councils, water was fit for irrigation except Thatta Khalil and Khurram Paracha where > 20 % of water samples were unfit. About 17 % water samples were unfit due to higher electrical conductivity (EC). Residual sodium carbonate (RSC) and sodium adsorption ratio (SAR) were higher in few water samples, while > 90 % water samples had RSC and SAR within prescribed safe permissible limits. The dominant cations were Ca ++ + Mg ++ and Na + with mean values of 7.6 and 3.3 me L -1 whereas, HCO3 - and Cl - were dominant anion with mean values of 4.2 and 3.0 me L -1 , respectively. The analytical data indicated that these waters had higher EC. However, the quality of available groundwater in the tehsil is suitable for raising trees and orchards. Guidelines of water for irrigation purpose should be based on the soil textural class for its maximum utilizationr and to avoid any potential harmful effects on soil health.