The current study was conducted in Qayyarah sub-district of Nineveh governorate on a
number of water wells (nine wells) and one site on the Tigris River, through which the
concentrations of some toxic heavy metals were estimated, such as (lead, chromium,
nickel), and it also included the measurement of some properties Other chemicals
(sodium and potassium ions, calcium and magnesium ions, and PH), in addition to
measuring some physical properties of well water and river water (electrical
conductivity and turbidity), and the results were compared with known global
determinants for the purpose of determining its suitability for irrigation purposes. The
results showed that all wells were unfit for irrigation purposes depending on the
electrical conductivity values, as for the pH values, it was shown that all wells water
and river water were within the permissible ranges, and the concentrations of sodium
and potassium ions indicated that they did not exceed the maximum permissible limits
for irrigation purposes, as for calcium Magnesium showed that eight wells were not
suitable for agricultural uses, and the studied concentrations of heavy metals (lead,
chromium, nickel) indicated that they did not record any value in the Tigris River, while
in the wells water it ranged between 0.019 – 0.538, 0.014 – 0.076, 0.041 – 0.960 mg.l-
1 respectively, and the results showed that the concentration of lead and chromium did
not exceed the maximum permissible limits, so it is considered suitable for agricultural
uses. As for nickel, high concentrations were recorded in five wells that exceeded the
maximum for irrigation purposes, according to the Food and Agriculture Organization
of the United Nations (FAO), which is 0.2 mg.kg-1, so it poses a threat to the soil system
and plants.