Appraisal of the Suitability of River Rido for Irrigation in Kaduna State, Nigeria

Abstract

The suitability of R iver Rido for irrigation purpose was determined through the assessment of the water quality . Twelve water samples we re collected and tested for pH, electrical conductivity (EC), total dissolved solids (TDS), sodium (Na), calcium (Ca), magnesium (Mg) potassium (K), ammonium nit rogen (NH 4 - N), arsenic (As), cadmium (Cd), chromium (Cr), copper (Cu) and iron (Fe). Sodium Adsorption Ratio (SAR) was derived from some of the measured parameters. EC and Mg had relatively higher values at the upstream compared to values observed downstr eam. The downstream was the section where the highest values of Na, Ca, K, NH 4 - N and SAR were found. The mean of EC was 122.1, PH 6.8, TDS 83.8, Na 14.7, Ca 14.5, Mg 6.5, K 17.3 and NH 4 - N 0.2. The values of pH, EC, TDS, Na, Ca, K and NH 4 - N were within t he allowable limits. The mean value of SAR was 4.55 meq/L; which indicated that the adsorption of sodium is excellent. The values obtained showed that the u s e o f t h e w a t e r f r o m R iver Rido for irrigation will not expose the soil to salinity and alkalinity hazards. However, the concentrations of heavy metals in the water makes it unsafe for irrigation, as it contaminates the crops cultivated and endangers the health of both man and animals that consume the crops. The highest values of As, Cd, Cr and Fe we re observed downstream with content levels of Cu being the only exception, out of the five heavy metals tested. To reduce the lev el of contamination, effluents discharged into the river by the Kaduna Refinery and Petrochemical Company (KRPC) should be treated to meet stand and set by the World Health Organisation and regulatory bodies ; and the Kaduna Environmental Protection Authority (KEPA) should monitor the activities of KRPC and make it comply with guidelines of industrial effluent discharge