Assessment of some groundwater wells in the west of Al Najaf city for by Water Quality Index (WQI)

Abstract

Najaf an Iraqi city considered an agricultural city.  Located southwest of Baghdad .this study was conducted for the purpose of evaluating the quality of well water in the South and West of Najaf through chose 32 a water well distributed in the region and analyzed chemically and physically. The results showed a variation of water quality in different locations. The test for validity of water for agricultural use it found that the electric conductivity EC ranged between (5305-2342) disisimnz-1 in Wells 6, 7, 9, 12, 13, 14, 16, 17, 21, 22, 26, 28, 30, 31, 32, where there is a clear increase in the values of electrical conductivity. Electrical conductivity values depend on the concentration of water and the quality of its salts, the SAR values ranging from (6812-0.92), so that the classification of these wells according to the specifications of the agriculture and food Organization  to determine the validity of the irrigation water was as follows: it was a very large TDS values exceeded the limits of risk of irrigation by this specification, the influence of sodium adsorption ratio SAR with EC electrical conductivity with impact (few-average) on agricultural crops , Na sodium values ranging from (51-1000) ppm so there is no impact on agricultural crops, Cl values ranging from (117-1375) ppm and bicarbonate ion HCO3 ranged between (58.507) ppm so it's not any problem when irrigation with this specification. The value of nitrates NO3 ranging from (3-700) ppm where the wells are 13, 15, 17, 30, NO3 ratio greater than 30 and that's very dangerous when irrigation with NO3. Either the wells 2s this range is allowed except wells number 22, 23, 32, were lower than the limits allowed by the specification. The results shows that the water is not safe for drinking and need to use treatment for animal handlers and agricultural crops