Evaluation of Irrigation Water Quality Index (IWQI) for Habbaniya Lake in Anbar Governorate, Iraq

Abstract

A study was conducted to estimate the Irrigation Water Quality Index (IWQI) for Habbaniya Lake in central Iraq for irrigation purposes. The samples were taken at sixteen stations in October 2019. Studied samples were examined for ten Physico-chemical parameters Hydrogen Number (pH), Electrical Conductivity (EC), Temperature (T °C), Total Dissolved Solids (TDS), Total Hardness (T.H.), Turbidity (NTU), Sodium Absorption Ratio (SAR), Na+, Cl-, and HCO3 -. The results showed that 68.75% of the study water samples fall within the low restriction category (LR) irrigation water in eleven stations (which is dominant in all parts) and 25% of the search region falls under the no restriction category (NR) irrigation water in four stations (which is dominant in the northwestern part at station 5-8). Meanwhile, a small part of the study area represents 6.25% of the water samples is classified as a moderate restriction (MR) irrigation water in one station (in the central part). Accordingly, these categories are suitable to use only with the soil having low to moderate permeability with a plant of some kind for specified tolerance of moderate salts content. The IWQI is homogeneous and suitable for irrigation in all parts, especially the northwestern part which represents the entrance waters through Warar Canal that fed principally from the Euphrates River.