Deterioration of groundwater quality due to drastic human interventions is rising at an alarming rate particularly in lower- and middle-income countries. Yet, limited research effort has been devoted to monitoring and ascertaining groundwater quality. The present study develops a comprehensive irrigation water quality index (IWQI) for rating water quality of shallow and deep aquifers in North Kurdufan province, Sudan. The new approach is developed to overcome the deficiencies of the existing irrigation indices and coming up with a unified decision for classifying water quality for irrigation purposes. Because of these indices like permeability index (PI), sodium absorption ratio (SAR), etc., depending on specific elements, entirely subjective, as well as the great variations in their results, particularly when classifying water quality. Thus, IWQI is created based on eight indices that are generally used to evaluate irrigation water quality, plus three physicochemical parameters have been proven an impact on water quality. The analytic hierarchy process (AHP) is applied to minimize the subjectivity at assign parameter weights under multiple criteria decision analysis tools (MCDA). The spatial distribution of IWQI agrees with the spatial distribution of the most parameters. The results of our approach reveal that the majority of samples are suitable for irrigation uses for both aquifers except few wells in the confined aquifer. Also, noted that there are very variations in the irrigation indices results for classifying water quality. The comparison result showed that the new index robust, fair calculations and has best classifying of water quality.

由于剧烈的人为干预造成的地下水质量恶化正在以惊人的速度上升，尤其是在低收入和中等收入国家。然而，有限的研究工作致力于监测和确定地下水质量。本研究开发了一个综合灌溉水质指数 (IWQI)，用于评估苏丹北库尔杜凡省浅层和深层含水层的水质。开发新方法是为了克服现有灌溉指标的不足，并为灌溉目的的水质分类提出统一的决定。由于渗透率指数（PI）、钠吸收率（SAR）等指标，取决于具体的要素，完全是主观的，而且其结果差异很大，特别是在对水质进行分类时。因此，IWQI 是根据通常用于评估灌溉水质的八个指标创建的，另外三个物理化学参数已被证明对水质有影响。应用层次分析法 (AHP) 来最小化在多准则决策分析工具 (MCDA) 下分配参数权重时的主观性。IWQI 的空间分布与大部分参数的空间分布一致。我们的方法的结果表明，除了承压含水层中的几口井外，大多数样品都适用于两个含水层的灌溉用途。此外，还注意到用于对水质进行分类的灌溉指数结果存在很大差异。比较结果表明，新指标稳健、公平，对水质的分类效果最好。