Integrating a GIS-based approach and a SWAT model to identify potential suitable sites for rainwater harvesting in Rwanda

Abstract

The increasing demand of water results in the overexploitation of water resources. This situation calls for more effective water management alternatives including rainwater harvesting (RWH) systems. Due to the lack of biophysical data and infrastructure, the identification of suitable sites for various RWH systems is a challenging issue. However, integrating geospatial analysis and modeling approaches has become a promising tool to identify suitable sites for RWH. Thus, this study aimed at identifying suitable sites for RWH in the Nyabugogo catchment located in Rwanda by integrating a geo-information-based multi-criteria decision-making (MCDM) and SWAT (Soil and Water Assessment Tool) model. Moreover, the sediment yield was compared to the soil erosion evaluated using the Revised Universal Soil Loss Equation (RUSLE) owing to the lack of sediment concentration measured data. The results revealed that about 4.8 and 16.35% of the study area are classified as highly suitable and suitable areas for RWH, respectively. Around 6% of the study area (98.5 km2) was found to be suitable for farm ponds, whereas 1.6% (26.1 km2) suitable for check dams, and 25.9% (423 km2) suitable for bench terraces. Among 50 proposed sites for the RWH structures, 29 are located in the most suitable area for RWH. The results implicated that the surface runoff, sediment yield, and topography are essential factors in identifying the suitability of RWH areas. It is concluded that the integrated geospatial and MCDM techniques provide a useful and efficient method for planning RWH at a basin scale in the study area.

Modelling the future climate impacts on hydraulic infrastructure development in tropical (peri-)urban region: Case of Kigali, Rwanda

“…The Stage-discharge Rating Curve (SRC) method is a statistical analysis technique to generate the discharge based on the stage levels and the field measurements [ 57 , 58 ]. A similar methodology was applied by Manyifika, [ 60 ], and Umugwaneza et al [ 59 ]. With regards to Birbal et al [ 61 ] and Kumlachew et al [ 62 ], the studies vow an excellent statistical performance of SRC with more than 0.95 correlation in actual versus calculated discharge values.…”

Identification of Suitable Rainwater Harvesting Sites Using Geospatial Techniques With AHP in Chacha Watershed, Jemma Sub-Basin Upper Blue Nile, Ethiopia

“…Soil having small and medium pores are more favorable for RWH development because of its high-water retention capacity. According to (Umugwaneza et al, 2022), the soil textural class of the study watershed was classified into highly, moderately, marginally suitable, and unsuitable and summarized in Table 1. (1996) Distance from the road (km) <0.5…”

EVALUASI FUNGSI LINGKUNGAN EMBUNG BERBASIS SISTEM INFORMASI GEOGRAFI: KASUS EMBUNG KRAPYAK DAN TONOGORO DI KULON PROGO, DAERAH ISTIMEWA YOGYAKARTA (Environment Role Evaluation of Retention Basins Using Geographic Information Systems: Case of Krapyak and Tonogoro in Kulon Progo, Special Region of Yogyakarta)

“…Embung dapat memenuhi fungsi lingkungan apabila dibangun pada lokasi yang tepat (Darabi et al, 2021). Umumnya embung dibangun pada lokasi yang dipilih berdasarkan area yang paling tepat (Umugwaneza et al, 2022) yakni di cekungan alur sungai yang dibendung (Kumar & Jhariya, 2017;Mahmood et al, 2020). Embung dapat dibangun di luar alur sungai yang merupakan cekungan alami sebagai tempat akumulasi aliran permukaan (Márquez et al, 2021).…”