Quality Assessment of Ashugonj Power Plant Disposal Water for Irrigation Application

Abstract

The study was conducted at Ashuganj agro-irrigation project, aimed to determine the chemical properties of power plant disposal water and to assess its suitability as irrigation water. Initial and final soil samples (before irrigating and after harvesting crop field)  and ten water samples (six from crop field and four from irrigation canals during irrigation period) were collected..  Soil samples were analyzed at Humboldt soil testing laboratory and water samples at bio-chemistry laboratory in Bangladesh Agricultural University (BAU). All laboratory obtained values were compared to Food and Agriculture Organizaiton (FAO) irrigation water standards. Results showed that sodium absorption ratio (SAR) (0.53 to 0.88), residual sodium bi-carbonate (0.8 to 1.3 meq L^-1), Kelly’s ratio (0.31 to 0.6) and total hardness (85 to 150) were found within  suitable range of water quality for irrigation application. Soluble sodium percentage values (20.26 to 41.1) were found within satisfactory  level but magnesium absorption (57.1 to 76.4) were found unsuitable for irrigation use. No significant difference was observed for pH, EC, total nitrogen, organic carbon, calcium, magnesium and phosphorus  between initial and final soil samples.However, potassium and sulfer  reduced in final soil samples than that ofinitial soil samples. The quality of power plant disposal water fall within the permissible limit recommended by FAO for irrigation water. So, it was found suitable for using as irrigation water in nearby crop fields.