The current research aimed at investigating the consequences of irrigation with wastewater of El-Gabal El-Asfar drain on the bioavailability of heavy metals (HM) on the long run. To achieve such goal, seventeen farms were selected from El-Gabal El-Asfar area to represent soils of different cropping periods ranging from <5 up to 70 years. Soils were analyzed for DTPA extractable Fe, Mn, Zn, Cu (micronutrients) and Co, Pb, Ni and Cd for three successive seasons. The highest DTPA extractable heavy metals were in soils of long cropping period except for Co which did not follow a certain trend patterns of DTPA-extractable heavy metals (except for Co) as affected by the cropping periods were identical confirming that the applied sewage water was the main cause of heavy metal contamination heavy metals in soils. DTPA extractable micronutrients were calculated on a logarithmic basic and assumed to be log-normally distributed. The central tendency and variation of data, expressed as the geometric means (GM) and geometric deviations (GD), were determined. The range of concentrations for the calculated GM/GD² and GMxGD² (‘baseline' values) were markedly wider than the observed concentrations for all heavy metals except for Ni. The results reflect the impact of the anthropic activity on Ni concentration in soil. Overall, DTPA- extractable heavy metals were significantly correlated with the cropping period, soil organic carbon, soil pH, soil and EC, but no significant correlation with CaCO_3. No significant correlations were detected between DTPA extractable Co and any of the studied parameters.