Selection of rainwater harvesting sites by using remote sensing and GIS techniques: A case study of Kirkuk, Iraq

Abstract

Arid and semi-arid areas such as Iraq suffer not only from limited precipitation but also from poor management of rainwater for agricultural use. One technique for rainwater harvesting (RWH) is to collect excess runoff water during the rainy season and store it for agricultural purposes during dry spells. Remote sensing (RS) and geographic information systems (GIS) are widely used to identify suitable RWH sites. In this study, an integrated approach was adopted to determine suitable RWH sites in Kirkuk City, Iraq. The methods were integrated with the multi-criteria decision analysis (MCDA) method to evaluate the parameters that significantly contribute to RWH site selection. Thematic layers, such as runoff depth, slope, drainage, and land use/land cover, as well as their features were assigned suitable weights and then integrated in a GIS to generate a RWH potential map of the study area. Suitable sites for different RWH structures, such as farm ponds and check dams, were also identified. The study area can be classified into three potential RWH zones: high suitability zone (8.2% or 399.75 km2), moderate suitability zone (63.4% or 3,090.75 km2), and low suitability zone (28.4% or 1,384.5 km2). Around 3.7% of the study area (181.6 km2) is suitable for farm ponds while 4% (197 km2) is suitable for check dams. The integrated RS, GIS, and MCDA techniques were found to be a cost-effective and environmentally friendly way to recover rainwater and select suitable RWH sites.