Untreated discharges from industrial, domestic, and storm waters, agricultural runoff, and other sources significantly affect the quality of irrigation water both on short- and long-term basis. The present study deals with the assessment of heavy metals in irrigation wastewater, soils, and wheat grains irrigated with contaminated water from municipal sources in Abbottabad, Pakistan. The concentrations of most of the metals were found above the threshold limits for irrigation water and food set by international regulations. The concentrations of metals in wheat grains showed a decreasing order of Zn>Fe>Mn>Cu>Pb>Cd>Ni>Cr in samples collected from areas irrigated with municipal wastewater. Grains were found to accumulate in Cr, Ni, and Fe metals, which were beyond recommended dietary limits. It is recommended that treatment facility must be installed to reduce heavy metals and turbidity of the wastewater being used for downstream irrigation.