The quality groundwater for irrigation in Fetzara basin, northeast Algeria

The Fetzara basin occupying an area of about 515 km2 is a part of the alluvial deposits of the Annaba plain. The main source of irrigation water in Fetzara basin is groundwater, hence its quality needs to be controlled; otherwise it can damage soil and reduce crop production. The aim of this study was to review hydro chemical processes that control the groundwater chemistry and to determine the suitability of groundwater for irrigation. Hydro chemical analysis has been carried out based on concentrations of Ca , Mg , Na , K , Cl-, SO4–, CO3– and HCO3-. Different irrigation quality parameters viz, salinity, Sodium Adsorption Ratio (SAR), sodium percentage (Na%), Residual Sodium Carbonate (RSC), Magnesium Hazards (MH), Kelly’s index (KI) and Permeability Index (PI) are calculated for the evaluation of groundwater quality for irrigation purposes. The evaluation of SAR (2.127-9.021) and EC (1240-6390 μS/cm) resulted in classification category ‘C3S1 and C4S1’, indicating high salinity and low sodium water which can be used for irrigation in most soils and crops with little to medium danger of development of exchangeable sodium and salinity. However, samples with doubtful Na% (56%), unsuitable KI and MH (88%, 64% respectively), and high salinity hazard (60%) values restrict the suitability of the groundwater for agricultural purposes, and plants with good salt tolerance should be selected for such ground waters.