INTRODUCTION<\/h2>\n
Pressure on water and natural resources in\u00a0the\u00a0world, exacerbated by climate change, is threatening agriculture, livestock and increasing poverty in\u00a0arid and semi-arid areas, especially in\u00a0rural, isolated localities. It is in\u00a0this context that rainwater harvesting (RWH) systems have gained importance internationally as a\u00a0sustainable rainwater management solution.<\/span><\/p>\n RWH is the\u00a0process of\u00a0collecting raindrops or runoff and storing them in\u00a0tanks, reservoirs, or other storage systems. The\u00a0harvested rainwater can\u00a0subsequently be utilized for various on-site purposes due to its limited captured volume. Rainfall can\u00a0be collected from different sources. RWH systems (RWHS) are designed to collect surface runoff from steep and sparsely forested mountain\u00a0slopes to agricultural areas [1]. As a\u00a0result, these systems serve a\u00a0dual purpose: providing water supply and managing floodwater, which makes them both distinctive and exceptional [2]. Okello et al. [3] claimed that in\u00a0addition to increasing the\u00a0availability of\u00a0water, RWH helps restore nearby groundwater sources and generates employment opportunities in\u00a0the\u00a0local communities. Consequently, the\u00a0widespread adoption of\u00a0RWH as a\u00a0strategic solution to water scarcity has contributed to a\u00a0reduction in\u00a0groundwater extraction. RWH has been employed not only to address the\u00a0growing imbalance between water supply and demand but also to promote social, environmental, and economic development, ultimately enhancing the\u00a0quality of\u00a0life in\u00a0arid and semi-arid areas [4\u20137].<\/span><\/p>\n Over the\u00a0past few decades, numerous researchers have shown their interest in\u00a0RWH technologies and practices, and also several countries worldwide have been using RWHS as an\u00a0alternative measure to provide water for domestic and agricultural uses in\u00a0dry and isolated areas. However, these RWHS differ from one location to another according to multiple criteria such as: the\u00a0geographical situation, land configuration, hydrographic network, purpose of\u00a0rainwater usage, socio-economic situation, local population preferences, and environmental contexts. Consequently, researchers try to combine all these criteria to design and implement an\u00a0adapted RWHS for a\u00a0specific location.<\/span><\/p>\n Current review studies primarily focus on the\u00a0benefits of\u00a0RWHS in\u00a0addressing water scarcity in\u00a0drought-prone areas [8, 9], the\u00a0modernization of\u00a0traditional RWHS [10, 11], their potential applications in\u00a0agriculture and livestock activities [12, 13], and the\u00a0integration of\u00a0new technologies to maximize RWHS performance [14, 15]. Nonetheless, these reviews have adopted diverse methodological approaches, and often include sources with varying levels of\u00a0scientific rigor, such as professional reports and book chapters. Furthermore, some focus narrowly on a\u00a0specific aspect of\u00a0RWH or are limited to particular regions, such as the\u00a0Middle East and North Africa (MENA) or low-and middle-income countries (LMICs). This disjointed perspective hampers a\u00a0comprehensive understanding of\u00a0the\u00a0global importance and diverse applications of\u00a0RWHS across multiple sectors. To address these gaps, this study conducts a\u00a0systematic literature review based on the\u00a0Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) framework, exclusively considering peer-reviewed articles published in\u00a0Scopus and ScienceDirect from January 2021 to December 2025. This structured and transparent methodology enhances reproducibility and offers a\u00a0thorough synthesis of\u00a0worldwide research. Distinct from earlier reviews on RWHS (e.g., [7, 16\u201319]), this study is organized to facilitate understanding of\u00a0the\u00a0complex structure of\u00a0RWHS, directed by crucial questions aimed at identifying the\u00a0scholarly advancements of\u00a0RWH, analyzing different research contributions in\u00a0RWH, and determining the\u00a0challenges of\u00a0rain\u00a0and flood water management policies. Throughout this scholarly pursuit, this study offers a\u00a0detailed synthesis of\u00a0the\u00a0main\u00a0principal RWH techniques, applications, and practices that exist worldwide. It emphasizes recent advancements and future perspectives for sustainable water resources management.<\/span><\/p>\n This paper is organized as follows: The first section presents the methodology of this study, highlighting the criteria used for selecting sources and studies using the PRISMA-based systematic literature review. The second part consists of a literature review that summarizes the results of all the reviewed articles. This section is organized into several parts: first, an overview of historical and traditional RWH techniques in arid and semi-arid areas; followed by a technical\u00a0<\/span>review of\u00a0RWHS, including types, design considerations, implementation sites, and maintenance practices. The\u00a0next section discusses the\u00a0impacts of\u00a0RWH on agriculture, livestock, and livelihoods in\u00a0rural areas, as well as its role in\u00a0managing food and water erosion. Finally, the\u00a0concluding section examines water management policies and institutional support mechanisms.<\/span><\/p>\n To conduct this review, the\u00a0methodology of\u00a0systematic literature review was used to collect, analyze, and evaluate a\u00a0certain\u00a0number of\u00a0scientific papers on RWH in\u00a0the\u00a0world. For this purpose, the\u00a0guidelines of\u00a0the\u00a0PRISMA were employed to guarantee an\u00a0organized and credible selection process. Moher et al. [20] introduced the\u00a0PRISMA statement as a\u00a0set of\u00a0directives aiming to enhance the\u00a0transparency and comprehensiveness of\u00a0reporting in\u00a0systematic reviews through a\u00a0defined set of\u00a0steps, containing article identification, screening, eligibility, and final inclusion.<\/span><\/p>\n RWH has become a\u00a0popular topic since the\u00a0early 2000s, with an\u00a0increase in\u00a0the\u00a0number of\u00a0publications over the\u00a0years [16]. Considering this extensive volume of\u00a0publications, the\u00a0studies included in\u00a0the\u00a0present review were carefully selected according to predefined eligibility criteria to ensure relevance and coherence. These eligibility criteria included peer-reviewed journal articles written in\u00a0English, published between January 2021 and December 2025, indexed in\u00a0Scopus and available in\u00a0ScienceDirect and Scopus, and related to rural RWH.<\/span><\/p>\n The\u00a0bibliographic databases used in\u00a0the\u00a0article search: ScienceDirect and Scopus. Particular keywords and terms related to rural RWH were utilized in\u00a0this search (Fig.\u00a01<\/span>). The\u00a0query was structured as follows: (\u201crainwater\u201d OR \u201cstormwater\u201d OR \u201csurface water\u201d) AND (\u201charvesting\u201d OR \u201ccollecting\u201d OR \u201cstoring\u201d OR \u201cmanagement\u201d OR \u201cconservation\u201d OR \u201cwater erosion\u201d) AND (\u201crural\u201d OR \u201cmountain\u201d OR\u00a0\u201carid\u201d OR \u201csemi-arid\u201d OR \u201cdry area\u201d) AND ( \u201cagriculture\u201d OR \u201clivestock\u201d OR \u201cfields\u201d) AND ( \u201ctechniques\u201d OR \u201cdesign\u201d OR \u201chydraulic system\u201d OR \u201cconstruction materials\u201d OR\u00a0\u201cimplementation site\u201d OR \u201cefficiency\u201d). Using this search strategy, an\u00a0initial dataset of\u00a01,854 publications was obtained.<\/span><\/p>\n Management of\u00a0the\u00a0references<\/span><\/strong><\/span><\/p>\n All the\u00a0retrieved publications from the\u00a0searches were imported into Zotero, which is a\u00a0reference management software [21] to identify and remove all the\u00a0duplicated publications. At this level, 79 papers were removed from the\u00a0dataset for being duplicates (Fig.\u00a02<\/span><\/em>).<\/span><\/p>\n Selection process<\/span><\/strong><\/p>\n After removing all the\u00a0duplicated records, a\u00a0second filter was applied on the\u00a0remaining 1,775 records based on the\u00a0article titles to ensure the\u00a0inclusion of\u00a0relevant content. Accordingly, articles that did not contain\u00a0the\u00a0predefined keywords (Fig.\u00a01<\/span><\/em>) in\u00a0the\u00a0title were excluded from the\u00a0database. Thus, 1,579 articles were removed, and the\u00a0number of\u00a0records at this stage decreased to 196. To further refine this dataset, a\u00a0third manual filter was applied using the\u00a0article abstracts, aiming to include only articles that align with these three main\u00a0topics:<\/span><\/p>\n Both authors conducted this process, and unclear cases were analyzed in\u00a0more detail and discussed until a\u00a0consensus decision was reached.<\/span><\/p>\n At the\u00a0end of\u00a0this process, 96 articles were excluded after reading the\u00a0abstract, and 100 articles were selected for additional analysis (Fig.\u00a02<\/span><\/em>).<\/span><\/p>\n Inclusion\/exclusion criteria<\/span><\/strong><\/span><\/p>\n After an\u00a0in-depth reading of\u00a0the\u00a0full-text articles meeting the\u00a0initial screening criteria, clear inclusion and exclusion criteria were established to confirm the\u00a0alignment with the\u00a0research main\u00a0themes (Tab.\u00a01<\/span><\/em>). As a\u00a0result of\u00a0this process, 89 articles were selected for further evaluation. The\u00a0entire screening process was documented using Zotero and Excel spreadsheets, including relevant notes for each article.<\/span><\/p>\n Data collection process<\/strong><\/span><\/p>\n All data relating to the\u00a089 selected articles were meticulously extracted and organized into an\u00a0Excel spreadsheet. This retrieved dataset includes key information, specifically authors\u2019 names, articles\u2019 titles, years of\u00a0publication, study locations, main\u00a0topics, abstracts, research methodologies, and results. This structured approach simplified the\u00a0analysis and guaranteed easy access to articles details for comparison and review.<\/span><\/p>\n Quality assessment<\/strong><\/span><\/p>\n The\u00a0methodological quality of\u00a0all the\u00a0included articles was evaluated based on two main\u00a0criteria:<\/span><\/p>\n \u00a0<\/span>This assessment was conducted manually by both authors, and notes on the\u00a0limitations of\u00a0each article were recorded in\u00a0Excel spreadsheets. According to these specified criteria, 8 articles were excluded due to weak methodology, and 15 articles were excluded due to the\u00a0absence of\u00a0relevance and validity of\u00a0findings. Following this assessment, 66 articles satisfied the\u00a0criteria and were selected for final inclusion.<\/span><\/p>\n Bias assessment<\/strong><\/span><\/p>\n Following the\u00a0quality assessment, a\u00a0bias assessment was conducted on the\u00a0remaining 66 articles using the\u00a0Critical Appraisal Skills Program (CASP) checklist. This evaluation focused on the\u00a0clarity of\u00a0the\u00a0research process, the\u00a0presence of\u00a0references, empirical data, and the\u00a0validity of\u00a0findings. Unlike the\u00a0previous quality assessment, no articles were excluded at this stage based on bias considerations, indicating that all the\u00a0included studies demonstrated an\u00a0acceptable level of\u00a0bias control and transparency.<\/span><\/p>\n Data synthesis<\/strong><\/span><\/p>\n The\u00a0definitive dataset containing 66 articles was analyzed using a\u00a0qualitative synthesis approach, enabling the\u00a0identification, organization, and examination of\u00a0each article\u2019s\u00a0findings and results. During this process, outcomes of\u00a0the\u00a0studies were summarized, compared, and heterogeneities were evaluated. Consequently, the\u00a0articles were categorized according to their focus areas into main\u00a0sub-topics, including RWH in\u00a0ancient and modern structures, RWH applications in\u00a0rural settings, floodwater and water erosion management, and water governance policies. This classification provided a\u00a0systematic overview of\u00a0the\u00a0existing literature.<\/span><\/p>\n The\u00a0PRISMA flow diagram<\/strong><\/span><\/p>\n At the\u00a0conclusion of\u00a0this process, a\u00a0PRISMA flow diagram (Fig.\u00a02<\/span><\/em>) was constructed manually to illustrate the\u00a0entire selection workflow, starting with the\u00a0initial identification of\u00a0records and ending with the\u00a0final inclusion.<\/span><\/p>\n This structured method ensures transparency and enhances the\u00a0reproducibility of\u00a0the\u00a0review.<\/span><\/p>\n The\u00a0findings synthesize information from the\u00a0selected literature and highlight representative examples from diverse regions. Due to the\u00a0heterogeneity in\u00a0geographical contexts and methodological approaches, the\u00a0strength of\u00a0evidence among the\u00a0reviewed studies is variable, which may influence the\u00a0generalizability of\u00a0the\u00a0conclusions. Consequently, the\u00a0overall confidence in\u00a0the\u00a0body of\u00a0evidence can\u00a0be considered moderate. Therefore, the\u00a0results should be interpreted with caution, taking into account the\u00a0inherent limitations of\u00a0the\u00a0available evidence.<\/span><\/p>\n To facilitate a\u00a0comprehensive analysis, the\u00a0articles from the\u00a0final inclusion were classified and organized into five sub-topics using Zotero:<\/span><\/p>\n RWH has long served as a\u00a0foundation stone of\u00a0water management in\u00a0arid and semi-arid regions, reflecting the\u00a0cleverness and cultural resilience of\u00a0communities challenging water scarcity. This part synthesizes recent studies that collectively highlight the\u00a0importance and the\u00a0diversity of\u00a0these traditional RWH practices and their cultural significance across the\u00a0Middle East, Asia, North Africa, and Sub-Saharan\u00a0Africa.<\/span><\/p>\n Subterranean\u00a0channels<\/span><\/strong><\/span><\/p>\n Subterranean\u00a0channel is one of\u00a0the\u00a0most advanced traditional RWH practices in\u00a0the\u00a0MENA region, designed in\u00a0a\u00a0way to reduce evaporation and increase efficiency. These underground water systems present differences from one country to another in\u00a0techniques and nomenclature: qanats, falaj or aflaj, or foggaras [5]. These systems use gravity to transport water from higher elevation aquifers to lower elevation farmlands. This technique not only provides water to areas with limited surface water accessibility but also reduces water evaporation. On the\u00a0other hand, Weerahewa et al. [22] introduced aflaj as a\u00a0hydraulic system inspired by local traditions and Islamic principles of\u00a0equity insuring fair water distribution in\u00a0the\u00a0Arabian\u00a0Peninsula.<\/span><\/p>\n <\/p>\n Cisterns<\/span><\/strong><\/span><\/p>\n These water storage systems permit water harvesting in\u00a0wet seasons to provide water during the\u00a0prolonged periods of\u00a0drought. Cisterns vary from one location to another, given their typology, construction materials, and they can\u00a0also be open reservoirs, as observed in\u00a0Sela in\u00a0the\u00a0Southern Transjordan\u00a0Plateau [23] or underground like sarn\u0131\u00e7, <\/span>known as traditional cisterns implanted in\u00a0Bozcaada (T\u00fcrkiye) to ensure water scarcity in\u00a0this island [24].<\/span><\/p>\n Surface water harvesting traditional techniques<\/span><\/strong><\/p>\n Surface water harvesting can\u00a0also refer to RWH and floodwater harvesting. This method is based on collecting and storing rainwater or floodwater in\u00a0soil, natural reservoirs, or underground for later use. According to Ben Hassen et al. [5], this ancient technique is largely practiced in\u00a0many arid and semi-arid regions around the\u00a0world:<\/span><\/p>\n In\u00a0Yemen, spate irrigation (e.g., Wadis<\/strong>)<\/span> is commonly used as an\u00a0ancient and traditional water management method. It is designed using earthen structures to redirect floodwaters by gravity from mountainous catchments to\u00a0agricultural fields to rapidly irrigate them [5].<\/p>\n<\/li>\n<\/ul>\nMETHODS<\/h2>\n
Eligibility criteria<\/h3>\n
Search strategy<\/h3>\n
![\"\"](\"https:\/\/www.vtei.cz\/wp-content\/uploads\/2026\/06\/Belkaf-fig-1-1.jpg\")
<\/a><\/h6>\nFig. 1. Strategy used in\u00a0the\u00a0search of\u00a0bibliographic databases<\/h6>\n
Screening and selection process<\/h3>\n
<\/a>Fig. 2. Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) flow diagram<\/h6>\n\n
Tab.\u00a01. Inclusion and exclusion criteria<\/h5>\n
<\/a><\/h3>\n\n
RESULTS AND DISCUSSION<\/h2>\n
\n
Historical and traditional RWH techniques in\u00a0arid and\u00a0semi-arid regions<\/h3>\n
<\/a>Fig. 3. Cross-section of\u00a0qanat system (source: [5])<\/h6>\n<\/a>\nFig. 4. Ancient Cistern in\u00a0central Morocco (source: authors)<\/h6>\n
\n
<\/a><\/em><\/p>\nFig. 5. The\u00a0jessour system in\u00a0Tunisia (source: [5])<\/h6>\n
\n
<\/a><\/h6>\nFig. 6. Spate irrigation system in\u00a0Yemen (source: [5])<\/h6>\n