Development and evaluation of irrigation water quality guide using IWQG V.1 software: A case study of Al-Gharraf Canal, Southern Iraq

Abstract

Abstract In Iraq, rivers represent the main sources of water. Over the past few decades, there has beenwidespread use of water quality indices (WQIs) to assess the quality of water for various uses. In this study, an irrigation water quality guide (IWQG V.1) and its software, designed by Visual Basic 6, was developed based on the specifications of the United Nations Food and Agricultural Organization (FAO) and Meireles et al (2010) irrigation water quality index (IWQI) developed in Brazil. A monthly dataset of Al-Gharraf Canal, in the southern region of Iraq, for three years (2013–2015) containing 612 measurements for 17 water quality parameters was used to evaluate this guide. The guide classified the canal water as (Moderate Restriction) with (65.57) degree score showing its suitability, based on the calculated indices, for use in irrigation of most local crops, assuming proper control of permeability and salinity. The results also showed the good performance of this software as an efficient tool to evaluate, giving the interpretation, advice, and solutions to manage the irrigation water quality and problems. There is a need to establish a long-term management strategic plan to protect Al-Gharraf as an important local water resource.