Groundwater recharge, community water security, and practical engineering solutions in Northern Ghana

Introduction

Background

Northern Ghana’s water security problem is defined by a recurring mismatch between wet-season rainfall and reliable dry-season water availability.

Published estimates show substantial spatial and methodological variability rather than one stable regional groundwater recharge rate. Atankwidi studies report about 2–13% of annual rainfall, with a long-term estimate indicating that nearly 6% of rainfall contributes to groundwater recharge (Martin, 2006). Monitoring across the White Volta Basin produced 2.5–16.5%, with a mean of 7–8% of rainfall for groundwater recharge (Obuobie et al., 2012). Local studies report 6.6–10.9% in the Nasia sub-catchment, an average of 8.9% in Gushiegu, and about 2% of rainfall for groundwater recharge in the crystalline basement aquifer of Talensi (Addai et al., 2016; Afrifa et al., 2017; Akurugu et al., 2020). These estimates are not directly interchangeable because they represent different aquifers, spatial scales, observation periods, and methods. Together, they show that groundwater recharge rates are highly uneven on spatial and temporal scales and that rainfall totals alone are a weak indicator of dependable groundwater availability. Table 1 summarizes the primary groundwater recharge evidence.

Table 1. Published groundwater recharge estimates relevant to Northern Ghana.

Values are reported as presented in the original studies. They are not directly comparable because aquifer settings, spatial scales, monitoring periods, and estimation methods differ. Legacy regional labels are interpreted under Ghana’s current five-region framework.

Groundwater recharge provides a more useful basis for analysis because it links rainfall to actual storage rather than apparent wet-season abundance. Recharge estimates are needed to judge sustainable aquifer use, but recharge is not identical to accessible yield because fractures, weathered-zone thickness, hydraulic conductivity, and borehole placement control whether stored water can be abstracted (Addai et al., 2016; Akurugu et al., 2020; Obuobie et al., 2012). In the Vea catchment, land-cover modelling produced 82.5 mm of surface runoff and 115.1 mm of shallow recharge under the untreated scenario (Larbi et al., 2020). This is evidence from a computer-modelling scenario rather than a measured regional recharge rate, but it illustrates how land conditions change the partitioning of rainfall between runoff and subsurface water storage.

Problem statement

The persistence of dry-season water insecurity in Northern Ghana shows that seasonal rainfall alone does not ensure dependable water supply. Published estimates range from about 2% of annual rainfall in Talensi to local values above 20% in parts of Gushiegu, while basin level means remain well below the highest local estimates (Afrifa et al., 2017; Akurugu et al., 2020; Obuobie et al., 2012). This variability in groundwater recharge rates means the problem cannot be described as a single regional groundwater recharge deficit. Dry-season insecurity reflects the interaction of limited effective recharge, uneven fractured-aquifer accessibility, rapid runoff and evapotranspiration losses, storage limitations, and infrastructure performance.

Local infrastructure studies show that these physical constraints are compounded by service and surface water storage failures. In Tolon District, 75.8% of 115 assessed boreholes were functional and 24.2% were defunct, while discharge from functioning boreholes ranged from 3 to 18 L/min (Abdul-Ganiyu et al., 2022). A bathymetric assessment of nine northern irrigation reservoirs reported storage-capacity losses of 8.54–34.12%, and a separate Upper East study found that all four assessed small reservoirs had already lost their dead-storage capacity to sediment (Adongo et al., 2020; Adwubi et al., 2009). These findings show that dry-season scarcity is produced by hydrological limits, poor reservoir maintenance, and the weak conversion of available water into reliable infrastructure service.

The consequences extend beyond hydrology. Northern Ghana is predominantly rural, and groundwater is widely regarded as the most viable potable water source. Around 80% of inhabitants are rural, and water access is closely tied to poverty reduction, farming, and livelihood stability (Carrier et al., 2008). When water becomes scarce in the dry season, households lose opportunities for gardening, livestock support, and year-round production. The result is reduced food security, constrained income generation, and dry-season out-migration (Adams et al., 2024; Northern Patriots in Research and Advocacy (NORPRA), 2023). Water insecurity in Northern Ghana is therefore both a hydrological problem and a livelihood problem. The problem is also institutional. Kwoyiga and Stefan (2019) argue that technical solutions alone are insufficient and that recharge interventions require supportive legislative and governance arrangements. Dry-season water insecurity in Northern Ghana is therefore both a recharge problem and an implementation problem.

Aim and objectives

The aim of this paper is to assess the main constraints to groundwater recharge in Northern Ghana and to evaluate the comparative feasibility of practical runoff-control and agroforestry-based responses for improving water security.

The objectives are to:

• Identify the main climatic and physical factors that limit groundwater recharge in Northern Ghana.
• Compare the suitability and feasibility of selected groundwater recharge and runoff-control interventions for improving dry-season water security.
• Examine the policy and governance conditions needed for the successful implementation of groundwater recharge interventions in Northern Ghana.

Significance of the review

This study is significant for engineering practice, rural livelihoods, and policy design. From an engineering perspective, it draws attention to groundwater recharge processes that should inform borehole siting and groundwater recharge design (Carrier et al., 2008; Okofo and Martienssen, 2022). From a livelihood perspective, it addresses a major constraint on dry-season gardening, year-round farming, and rural stability (Adams et al., 2024; Northern Patriots in Research and Advocacy (NORPRA), 2023). From a policy perspective, it shows why technical measures must be matched with stronger governance, maintenance, and legislative support if boreholes are expected to perform over a longer period of time (Kwoyiga and Stefan, 2019). The study, therefore, treats groundwater recharge as a hydrological issue with direct social and institutional consequences.

Review gap and contribution

Existing syntheses address Ghana’s water resources under climate and anthropogenic stress (Agodzo et al., 2023), groundwater development in the lower White Volta basin (Agyemang et al., 2025), and hydrological challenges and agricultural opportunities in Northern Ghana under climate change (Kpiebaya et al., 2025). The present review adds a different integration by tracing a rainfall-to-service chain across groundwater recharge, aquifer accessibility, infrastructure condition, land-restoration practices, and institutional feasibility. It distinguishes recharge as water entering the groundwater system, groundwater availability as water stored in hydraulically accessible aquifers at useful abstraction yields, and water security as reliable, safe, and equitable service to users. The resulting insight is that a moderate regional recharge estimate can coexist with local water insecurity when aquifer accessibility, infrastructure condition, or management fails. The review therefore asks which bottleneck prevents wet-season water from becoming dependable dry-season service and uses that bottleneck-first framing to compare land-surface, surface-storage, aquifer-storage, and governance responses.

Review approach and scope

This article used a structured critical narrative review design to examine groundwater recharge, community water security, and practical engineering responses in Northern Ghana. No formal review protocol was preregistered, and the study was not designed as a systematic review or meta-analysis. Instead, the review used a transparent targeted-search, eligibility, qualitative evidence-appraisal, and thematic-synthesis process to compare evidence, identify disagreement, and assess implementation relevance across heterogeneous study designs and outcomes.

Literature identification and synthesis

Targeted searches were conducted through Google Scholar, the Food and Agriculture Organization International System for Agricultural Science and Technology (FAO AGRIS), PubMed and PubMed Central, and publisher and institutional platforms including ScienceDirect, SpringerLink, Wiley Online Library, Oxford Academic, MDPI, University of Ghana repositories, CSIR Space, and the University of Bonn repository. The targeted update was completed on 23 July 2026. The main publication window was from the year 2000 to July 2026. Earlier foundational studies were retained when they established widely used dryland practices or concepts, including zaï, stone lines, and landscape restoration.

Literature identification during manuscript development was iterative rather than a single one-time database search. The 23 July 2026 date marks the final targeted update before initial submission, not the beginning of literature identification. The original critical narrative review drew on the databases, publisher platforms, institutional repositories, and reference-list checking described above, but contemporaneous record-level retrieval counts were not retained for every route. Historical counts were therefore not retrospectively reconstructed. To improve reproducibility during revision, a standardized verification and update search was conducted on 18–19 August 2026 using the same thematic domains and eligibility logic, with the publication window extended through 19 August 2026.

Searches combined geographical terms with process, infrastructure, intervention, and governance terms. Core combinations included “groundwater recharge” with “Northern Ghana,” “White Volta,” “Atankwidi,” “Nasia,” “Talensi,” or “Gushiegu.” Infrastructure searches combined “borehole,” “small reservoir,” or “irrigation dam” with “functionality,” “maintenance,” “sedimentation,” or “performance.” Intervention searches used “stone bund,” “stone line,” “zaï,” “half-moon,” “sand dam,” “managed aquifer recharge,” or “aquifer storage and recovery” with “Ghana,” “Sahel,” or “dryland.” Governance and land-restoration searches combined “agroforestry,” “farmer-managed natural regeneration,” “governance,” “land tenure,” or “tree tenure” with “Northern Ghana.” Reference lists of key studies were also checked for additional primary evidence.

For the revision-stage verification, the thematic strategy was standardized into nine search blocks covering groundwater recharge and hydrogeology; boreholes, reservoirs, and infrastructure; stone lines, zaï, and half-moons; supportive soil-cover practices; agroforestry and farmer-managed natural regeneration; sand dams; managed aquifer recharge and aquifer storage and recovery; governance, gender, and livelihoods; and climate change and water resources. Count-based searches were run in FAO AGRIS and PubMed Central. Google Scholar was used for supplementary discovery and citation searching, while publisher platforms, institutional repositories, and reference-list checking remained supplementary routes and were not assigned retrospective retrieval counts. Platform-adapted verification strings and screening decisions are reported in Supplementary Table S1, which also provides the 65-source extraction matrix with study context, design, key evidence, limitations, and evidence directness.

Studies were eligible when they presented empirical, model-based, or clearly documented evidence on recharge, rural water infrastructure, soil and water conservation, agroforestry or farmer-managed natural regeneration, or implementation conditions relevant to the five present-day northern regions. For this review, “clearly documented evidence” required an identifiable study setting, a traceable method or data source, and a reported outcome relevant to recharge, storage, infrastructure performance, or water-service reliability. Studies from Burkina Faso, Niger, Kenya, and comparable Sahelian drylands were retained only where Ghana-specific field evidence was limited and the physical or institutional setting was sufficiently transferable. Duplicate records, opinion pieces, news reports, studies without traceable methods, and papers focused only on climate or water quality without a direct link to recharge, storage, or service reliability were excluded.

Peer-reviewed research was prioritised for quantitative and causal claims. Theses, government reports, non-governmental organisation (NGO) reports, conference or working papers, and institutional documents were retained only when they had identifiable institutional provenance and provided unique local evidence on policy, programme performance, infrastructure condition, or historical administrative boundaries. Grey-literature claims were checked against peer-reviewed evidence where possible and were not used alone to infer hydrological effectiveness or causal recharge benefits.

Evidence was synthesised thematically rather than statistically. Each source was examined by location, administrative framework, study design, aquifer or landscape setting, intervention, reported outcome, and stated limitation. A structured qualitative appraisal considered five dimensions: methodological transparency, directness of the measured outcome, geographical relevance or transferability to Northern Ghana, consistency with other evidence, and the limitations acknowledged by the source. Evidence was then described as direct field or monitoring evidence, modelled or scenario evidence, transferable evidence from comparable drylands, or institutional/conceptual evidence. No numerical risk-of-bias score was assigned because the included designs and outcomes were too heterogeneous for a common instrument; instead, evidence directness and study limitations were used to weight the strength of claims. Recharge estimates were retained in millimetres per year and as a percentage of annual rainfall where available and were compared descriptively rather than pooled.

The initially submitted evidence base contained 46 review sources. During revision on 18–19 August 2026, 10 eligible peer-reviewed studies were initially added. The standardized count-based AGRIS and PubMed Central verification search returned 72 retrieval instances (40 and 32, respectively). After consolidation of repeated provider/version records and duplicate titles, 52 unique records were screened. Twenty-eight were excluded at title/abstract stage because they were outside the geographic or transferability scope or lacked a direct link to recharge, storage, infrastructure performance, interventions, or dry-season service. Twenty-four records underwent full-text assessment; seven were excluded as redundant, insufficiently direct, or superseded by stronger evidence. Seventeen met the eligibility criteria; eight overlapped with the 10 studies already incorporated during the same 18–19 August revision process and nine were additional. Thus, the combined literature update and verification added 19 new peer-reviewed studies, increasing the evidence base from 46 to 65 sources: 55 peer-reviewed journal articles and 10 other published or institutional sources. Google Scholar approximate totals were excluded from the numerical flow. NASA POWER and UN OCHA datasets are not counted as review sources. Because study designs, outcomes, scales, and estimation methods differed, pooled effect sizes were not calculated.

As a critical narrative review, the process did not use formal Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) screening or meta-analysis. Publicly available National Aeronautics and Space Administration Prediction of Worldwide Energy Resources (NASA POWER) data were used only as descriptive climate context (NASA POWER Project, n.d). The three fixed locations were used to provide illustrative coverage of the former Northern, Upper East, and Upper West regional framework that appears in much of the earlier literature; they were not selected as statistical regional centroids and are not interpreted as region-wide averages. The 2011–2025 period provides a recent common period for the displayed variables and locations, but it is not a 30-year climate normal and is not used to infer long-term climate trends. Monthly values were averaged by calendar month at each location, and corrected precipitation values reported in millimetres per day were converted to monthly totals using the number of days in each month before the monthly climatology was calculated. The climate data were not used to estimate groundwater recharge, test causal relationships, or generate regional climate projections. OpenAI’s ChatGPT (GPT-5.6 Thinking; OpenAI, San Francisco, CA, United States) was used to assist with language refinement, document-formatting review, and development and revision of figure-layout code. All artificial intelligence (AI)-assisted outputs were checked, revised, and approved by the authors, who take full responsibility for the manuscript.

Groundwater recharge and water security in Northern Ghana

Study area and climate context

This review uses Northern Ghana to refer to the combined territory of the five present-day northern regions: Northern, Savannah, North East, Upper East, and Upper West. Ghana currently has 16 administrative regions. Much of the literature reviewed here was produced under the former 10-region structure, when this same broad study area was represented by the Northern, Upper East, and Upper West Regions. The former Northern Region was subsequently divided into the present Northern, Savannah, and North East Regions (Local Government Service, n.d; Northern Regional Coordinating Council, n.d). Regional names from earlier studies are therefore retained and interpreted according to the boundaries in force when each study was conducted (Figure 1).

The study area map uses the current five-region framework (Figure 1). The NASA POWER figures retain the former three-region labels to preserve consistency with the selected coordinates and earlier literature. The NASA POWER series represent three fixed locations labelled Upper East, Upper West, and Northern Region, rather than spatial averages for either the former three regions or the five present-day regions. They are included only as contextual support for established seasonal climate patterns and are not treated as original field data, region-wide estimates, or a basis for new recharge modelling.

The area lies within the tropical semi-arid Sudan-Savanna zone and has a strongly seasonal climate, marked by one unimodal rainy season and a long dry season (Martin, 2006; Obuobie et al., 2013; Umukiza et al., 2024). The rainy season generally begins in April or May, peaks in July and August, and declines by October, while the dry season lasts from about October or November to April (Obuobie et al., 2013; Okofo and Martienssen, 2022; Yidana et al., 2014). This pattern is also evident in the NASA POWER climatology. Mean monthly rainfall at the three representative locations remains low from November to March, increases sharply from April, and is concentrated between May and September, with the highest monthly totals in July and August (Figure 2a).

Rainfall is not only seasonal but unevenly distributed in space. Literature reports annual rainfall of roughly 800–1,140 mm across much of Northern Ghana, with lower totals in the far north and higher totals in some localities (Ewusi et al., 2020; Obuobie, 2008; Obuobie et al., 2012; Okofo and Martienssen, 2022). The fixed-location climatology reflects this spatial contrast during the wettest months, while also showing that most rainfall is delivered within a short part of the year (Figure 2a). Recharge opportunity is therefore concentrated into a limited seasonal window.

Temperature conditions reinforce this constraint. Mean monthly maximum temperatures peak from February to April, just before the main rains, decline during the wet season, and rise again as the dry season develops (Figure 2b). The location labelled Upper West records the highest pre-rain maximum temperatures.

Minimum temperature follows a smoother seasonal cycle, rising from January toward April or May, remaining relatively high through much of the wet season, and falling again toward December (Figure 2c).

These temperature patterns agree with earlier studies showing persistent heat and strong pre-rain thermal stress in Northern Ghana (Obuobie et al., 2013; Okofo and Martienssen, 2022; Umukiza et al., 2024). Atmospheric moisture also changes sharply with season. Mean monthly relative humidity rises from March or April, remains high through the rainy season, and peaks around August to October before dropping strongly in the dry months (Figure 3a). The location labelled Upper West is especially dry early in the year.

This seasonal humidity cycle is consistent with Harmattan-related dryness in the dry season and moist monsoon conditions during the rains (Umukiza et al., 2024; Yidana et al., 2014; Yidana and Koffie, 2014). Wind speed varies less than rainfall and humidity, but the monthly climatology shows relatively stronger winds from December to February and weaker winds during the peak wet-season months (Figure 3b).

Together, the monthly rainfall, temperature, humidity, and wind patterns describe a short-wet season followed by a long period of limited rainfall and strong evaporative demand. This seasonal setting helps explain why groundwater levels rise mainly during the rains and decline through the dry season, as reported by Obuobie et al. (2012) and Obuobie (2008).

Dry-season water insecurity in rural communities

Dry-season water insecurity in rural Northern Ghana is severe because water storage systems (reservoirs) fail precisely when demand remains high. Surface-water structures often dry up or become unreliable, while groundwater systems frequently underperform. The result is a prolonged seasonal gap in which households, livestock keepers, and farmers face reduced access to usable water for irrigation (Akudago et al., 2009; Carrier et al., 2008; Dovie and Kasei, 2018; Northern Patriots in Research and Advocacy (NORPRA), 2023).

This insecurity matters because it affects crop productivity as well as domestic water use. Inability to secure dry-season water limits gardening, reduces cropping opportunities, weakens income generation, and increases livelihood instability (Adams et al., 2024). The water problem is therefore not only one of access but is also one of seasonal economic opportunity.

Groundwater dependence in Northern Ghana

Groundwater occupies a central place in Northern Ghana because it is widely regarded as the most dependable source of potable water in rural settings. This dependence increases the importance of recharge. If recharge remains weak, then the main source relied upon by rural communities becomes progressively less dependable during the dry season (Carrier et al., 2008).

Dependence on groundwater also raises the cost of hydrological misjudgment. A focus on rainfall alone may encourage the assumption that a wet season guarantees dry-season security, yet the evidence shows otherwise. The practical question is not whether rain fell, but whether enough of it entered storage that communities can still use months later.

Main physical controls on groundwater recharge

Recharge in Northern Ghana is controlled by interacting climatic, soil, topographic, and geological factors. Climatic conditions matter first because much of the rain falls in intense storms over a short period, creating conditions that favour runoff rather than slow infiltration (Liebe et al., 2005). High evaporative demand further reduces the proportion of infiltrating water that survives long enough to reach deeper storage (Ewusi et al., 2020; Yidana et al., 2014). This means the climate does not merely set the background for recharge. It actively limits recharge efficiency.

Soil properties also matter because crusting, compaction, and clay-rich layers can sharply reduce infiltration or increase near-surface evaporation losses (Nguru et al., 2026; Pasiecznik and Reij, 2020; Yidana et al., 2014). Topography influences whether water ponds long enough to infiltrate or is rapidly shed downslope (Okofo and Martienssen, 2022). Geology then determines whether infiltrated water can move into useful storage zones or remains trapped in limited shallow systems (Carrier et al., 2008). These controls do not act independently. Intense rainfall on degraded or crusted surfaces tends to generate runoff, and even when infiltration occurs, unfavourable soils, shallow barriers, and strong evaporative demand can still prevent effective recharge. This is why recharge in Northern Ghana cannot be understood as a simple function of rainfall amount.

Why rainfall does not translate into reliable groundwater storage

Rainfall does not automatically become reliable groundwater storage because multiple losses occur between rainfall and aquifer replenishment. Part of the rain becomes immediate runoff, especially during high-intensity events. Part infiltrates only to shallow soil depths and is later lost to evaporation. Part never reaches productive aquifer zones because soils and geology restrict downward movement (Liebe et al., 2005; Obuobie, 2008; Yidana et al., 2014).

Northern Ghana’s water problem is therefore a conversion problem: wet-season rainfall does not consistently become durable dry-season storage. Annual rainfall totals are insufficient; the key issue is how rainfall is partitioned among runoff, shallow soil storage, evapotranspiration, and aquifer recharge. Figure 4 summarizes these pathways and intervention points.

Main constraints to groundwater recharge

Runoff losses

One of the clearest constraints to recharge in Northern Ghana is the large share of seasonal rainfall lost as runoff. High-intensity storms promote rapid overland flow, especially where land cover is poor and infiltration is limited (Liebe et al., 2005). Runoff reduces the time water remains on the land surface, which reduces the opportunity for infiltration and percolation.

Runoff is therefore important for two reasons. It removes water that might otherwise contribute to recharge, and it concentrates erosion and sediment transport that further degrade infiltration conditions over time. In this sense, runoff is not only an immediate hydrological loss but also a driver of longer-term land degradation.

Low infiltration and soil crusting

Low infiltration is another major barrier to recharge. Soil crusting reduces the rate at which rainfall can enter the soil, particularly after surface degradation or vegetation loss. Where crusts form, rainfall is more likely to pond briefly and then run off, especially during intense storms (Pasiecznik and Reij, 2020; Roose et al., 1999). This makes soil condition central to recharge. Even where rainfall is sufficient, crusted or compacted surfaces prevent the system from converting rainfall into stored moisture and deeper percolation. Recharge failure is therefore often a soil-function problem rather than a rainfall problem alone.

Land degradation and vegetation loss

Land degradation weakens recharge by altering the physical condition of the land in ways that favour runoff over infiltration. Vegetation loss intensifies this by removing protective cover, reducing soil organic matter, and weakening the biological pathways that help water move into the soil (Ilstedt et al., 2016; Owuor et al., 2016; Pasiecznik and Reij, 2020).

This matters because degraded land both sheds more water during storms and stores less afterward. Vegetation loss therefore reduces recharge directly and indirectly. It increases runoff in the short term and weakens soil structure over time.

Soil and geological limitations

Recharge is also constrained by unfavourable soils and aquifer conditions. Yidana and Koffie (2014) report that water moving through clay-rich profiles can suffer heavy evaporative loss before reaching deeper storage.

Geological conditions further limit storage and movement in parts of Northern Ghana, especially where aquifer properties are poor or discontinuous (Carrier et al., 2008; Obuobie et al., 2012).

These limitations are critical because they explain why infiltration alone is not enough. A site may allow some water into the soil and still perform poorly as a recharge zone if deeper transmission and storage are weak. Good recharge therefore depends on both surface infiltration and subsurface suitability.

Pressure on existing rural water systems

The condition of rural water infrastructure provides direct evidence that dry-season insecurity is not explained by recharge alone. Borehole breakdown, low discharge, reservoir sedimentation, weak maintenance finance, and limited access to spare parts reduce service even where groundwater or surface storage remains physically present (Abdul-Ganiyu et al., 2022; Adeenze-Kangah, 2022; Adongo et al., 2020; Osumanu et al., 2022). Infrastructure performance must therefore be treated as part of the water-security system rather than as an outcome separate from recharge.

Infrastructure failure also feeds back into water insecurity by increasing pressure on the few functioning sources that remain. This means that limited recharge is not only a background hydrological issue. It becomes visible through the performance of water systems that communities rely on every day.

Summary of key recharge barriers

Taken together, the main barriers to recharge are runoff loss, low infiltration, land degradation, difficult soils, unfavourable geology, and weak infrastructure performance. These are reinforcing constraints rather than isolated problems. High-intensity rainfall acting on degraded land promotes runoff. Poor soils and geology then reduce the value of the water that does infiltrate. The result is a system in which seasonal rainfall produces only limited dependable storage.

Practical groundwater recharge and runoff-control solutions

Selection basis for the methods reviewed

The methods reviewed in this paper were selected because they respond to the main barriers identified in Northern Ghana and because the literature supports them as plausible interventions in semi-arid conditions with strong runoff losses, seasonal rainfall concentration, and widespread land degradation. Taken together, they represent two broad directions of action. One direction focuses on slowing runoff and increasing infiltration directly within fields and across degraded landscapes. The other focuses on capturing water at broader scales or redirecting it into suitable subsurface storage. This distinction is important because the recharge challenge in Northern Ghana is not caused by a single process. Some water is lost rapidly as surface runoff, some is lost because soils are crusted or degraded and unable to absorb it, and some potential storage options depend on whether local subsurface conditions are favourable. A useful solution set must therefore include both simple landscape-based methods and more engineered recharge approaches.

Strength and directness of intervention evidence

The updated evidence base remains uneven across intervention classes. Contour bunds, stone lines, zaï pits, and half-moons have direct field evidence for runoff, soil moisture, vegetation recovery, crop yield, and, in Northern Ghana, zaï-related welfare outcomes (Ehiakpor et al., 2019), but these endpoints are not equivalent to measured deep aquifer recharge. Ghana-specific FMNR and tree-management studies strengthen evidence on tenure, social equity, farmer preferences, and local management context (Hansen et al., 2012; Kandel et al., 2021, 2022), whereas hydrological recharge mechanisms still draw partly on broader dryland evidence. Sand-dam evidence remains transferable but now includes monitored or field-based studies from Kenya and Zimbabwe (Lazurko et al., 2024; Ritchie et al., 2021, 2023). Ghana-specific MAR site-selection evidence is available for granitic aquifers (Acheampong et al., 2024), but long-term Northern Ghana field validation remains limited. Table 2 therefore separates evidence type from reported outcome and uses cautious language where the measured endpoint is indirect.

Table 2. Comparative assessment of recharge, runoff-control, and supporting water-security interventions for Northern Ghana.

Evidence type distinguishes direct field or monitoring evidence, modelled or scenario evidence, transferable evidence from comparable drylands, and institutional or conceptual evidence. Overall fit is a qualitative synthesis of evidence directness, hydrological suitability, spatial applicability, cost, labour demand, maintenance, and governance requirements. “High” indicates relatively broad applicability supported by direct or consistent evidence and manageable implementation demands; “high to moderate” indicates meaningful potential with stronger site or input constraints; and “selective” indicates potentially valuable options that depend on specific hydrogeological, infrastructural, or institutional conditions. These categories are decision aids rather than numerical scores or meta-analytic rankings and may change by site.

Contour bunds and stone lines

Among the most practical field-scale methods are contour bunds and stone lines. Stone lines are low barriers of stones laid approximately along contour lines across a slope, rather than complete boundaries around individual plots. Together with earth bunds, they slow overland flow, spread runoff, trap sediment, and increase the time available for infiltration. Field evidence supports these mechanisms but also shows that design and nutrient management matter. In Burkina Faso, plots without stone lines lost 31% of rainfall as runoff, while 25 m spacing reduced runoff by 23% and doubled sorghum straw and grain yield (Zougmoré et al., 2000). In the Upper East Region, two seasons of field and satellite observations found higher infiltration, soil moisture, vegetation performance, and sorghum yield in stone-bund plots (Tefera et al., 2024). A five-year Burkina Faso study also found that stone lines alone did not maintain soil fertility under continuous unfertilized sorghum, which supports combining runoff control with soil-fertility management (Zougmoré et al., 2002).

Zaï pits and half-moons

Zaï pits and half-moons address the same broad problem at a localized scale by concentrating runoff around plants and breaking crusted surfaces. Half-moons are semicircular earthen basins or embankments constructed along the contour, with the open side facing upslope, to capture and pond runoff around crops or planted vegetation. In Northern Ghana, propensity-score analyses found higher welfare outcomes among zaï adopters than comparable non-adopters, strengthening the local economic and adoption evidence without demonstrating deep recharge (Ehiakpor et al., 2019). Sahelian field evidence shows that zaï can restore cereal production on degraded soils but requires substantial labour and organic matter (Roose et al., 1999). Half-moon trials in Burkina Faso further show that water capture alone is insufficient on nutrient-poor crusted soils: compost or manure produced sorghum yields of 900–1,600 kg/ha, 20–39 times the yield of unamended half-moons (Zougmoré et al., 2003).

Mulch, compost, manure, and residue cover

Supportive soil-management practices play a different but equally important role. Mulch, compost, manure, and residue cover improve infiltration and water retention by changing the soil surface and improving soil condition. They reduce evaporation, improve the soil’s ability to absorb water, support better soil structure, and reduce the risk of crusting (Nguru et al., 2026; Owuor et al., 2016; Winterbottom et al., 2013). Reduced tillage with soil cover contributes in a similar way by conserving soil structure and reducing the disturbance that often weakens infiltration and accelerates moisture loss, especially where degraded tillage practices have already damaged soil condition and where residue can be retained (Owuor et al., 2016; Winterbottom et al., 2013). These practices are not best understood as stand-alone capture systems. Their main contribution is to strengthen the soil environment into which water must infiltrate. In that sense, they are enabling measures. They may not intercept large runoff volumes on their own, but they improve the performance of other recharge and runoff-control interventions by making infiltration more likely and more durable over time.

Sand dams and percolation ponds for suitable seasonal sandy streams

At a broader scale, some methods aim to store water within channel deposits or direct it toward useful aquifers. Sand dams store water in accumulated sand within suitable ephemeral channels. Reviews and monitored Kenyan handpump data show site-to-site variation in sediment retention, leakage, water quality, siltation, and dry-season abstraction (Ritchie et al., 2021, 2023). Independent field evidence from 20 sand dams used by 19 villages in semi-arid Zimbabwe found that the mean period of water collection increased from 6.5 to 10.9 months per year and from 5.8 to 9.6 months in drought years after construction (Lazurko et al., 2024). These results strengthen evidence for dry-season access but remain transferable rather than Ghana-specific. Recent Botswana evidence further shows that sand-dam suitability depends on watershed morphometry, geology, bedrock conditions, runoff, and sediment supply (Nthokwa et al., 2025). Percolation ponds and managed aquifer recharge require permeable recharge zones, suitable aquifers, source-water control, and monitoring (Kwoyiga and Stefan, 2019; Okofo and Martienssen, 2022), so these options remain selective rather than uniform regional applications.

These methods differ in spatial applicability. Field-scale measures address widespread runoff, crusting, and infiltration constraints, whereas sand dams and percolation structures depend on more specific channel, aquifer, and institutional conditions. Intervention selection should therefore follow the dominant local loss or storage bottleneck rather than a universal regional prescription.

Comparative assessment of the selected solutions

Hydrological fit and regional applicability

The comparison of these methods shows that their suitability for Northern Ghana cannot be judged by hydrological promise alone. Their practical value depends on the balance between hydrological fit, technical simplicity, labour and cost burdens, maintenance demands, community applicability, and wider environmental and livelihood benefits. This broader comparison is necessary because the strongest method in purely technical terms is not always the strongest option in practice.

From a hydrological perspective, the strongest broad-fit methods are those that act directly on runoff loss and infiltration failure. Field evidence supports this mechanism, but it also shows that outcomes depend on design and site conditions. In Burkina Faso, plots without stone lines lost 31% of rainfall as runoff, while 25 m stone-line spacing reduced runoff by 23% and doubled sorghum yield (Zougmoré et al., 2000). In the Upper East Region, stone-bund plots retained more soil moisture at 10 and 20 cm depth, showed stronger vegetation performance, and produced higher sorghum yields than control plots across two seasons (Tefera et al., 2024). These studies provide direct evidence for soil-water retention and agronomic benefit. They do not by themselves prove deep aquifer recharge. Table 2 therefore separates demonstrated field-scale effects from inferred or modelled recharge benefits.

Engineered recharge options such as managed aquifer recharge (MAR) and aquifer storage and recovery (ASR) may offer an even stronger hydrological response where floodwater surpluses and aquifer conditions are suitable (Okofo and Martienssen, 2022; Owusu et al., 2017). Their hydrological fit is therefore high, but only under selected conditions. This means hydrological strength alone is not enough to determine priority. Breadth of applicability also matters. A method that works powerfully in limited sites is not equivalent, in strategic terms, to one that can be used across much of the semi-arid farming landscape. The comparison therefore suggests that field-scale methods hold greater regional breadth, while engineered recharge holds greater site-specific intensity.

Technical simplicity

Technical simplicity pushes the comparison further. Methods such as zaï pits, half-moons, mulch-based practices, and some bunding approaches are relatively simple because they rely on local materials and do not require advanced engineering or uncommon equipment (Nguru et al., 2026; Winterbottom et al., 2013). By contrast, MAR, ASR, and related engineered systems require stronger hydrogeological evidence, site investigation, and institutional capacity (Kwoyiga and Stefan, 2019; Okofo and Martienssen, 2022). They may be technically powerful, but they are not simple. This gives field-scale and community-scale methods an important practical advantage when the goal is broad adoption under real rural conditions. In effect, simplicity increases scalability, even when it does not always maximize recharge per site.

Cost, labour demand, and economic return

Cost and labour demand reveal one of the clearest trade-offs in the comparison. Many of the simpler methods are financially accessible because they rely on local materials, yet they can place heavy demands on household labour (Nguru et al., 2026). Digging zaï pits, constructing bunds, and transporting stones require substantial manual effort (Nguru et al., 2026; Partey et al., 2018; Roose et al., 1999; Winterbottom et al., 2013). Their low cash cost does not remove the burden they place on labour-constrained households. Even so, the economic evidence shows that these labour demands can be offset by strong returns. Zaï pits generate a net farm profit of 181 United States dollars (USD) per hectare compared with 41 USD under conventional systems, while compost applied with stone bunds generates annual economic gains of 260–323 USD per hectare (Partey et al., 2018). Water harvesting combined with conservation agriculture increases gross margins by four to seven times and improves return on labour by two to three times (Winterbottom et al., 2013). These figures show that labour-intensive methods are not necessarily economically weak. Their challenge is less profitability than the ability of households to mobilize labour upfront.

The agronomic evidence strengthens the case for field-scale interventions, while also warning against treating yield gains as direct recharge measurements. Stone lines doubled sorghum straw and grain yield in a Burkina Faso field experiment, and Upper East stone-bund plots produced consistently higher sorghum yields than control plots (Tefera et al., 2024; Zougmoré et al., 2000). Zaï practices have restored cereal production on severely degraded Sahelian soils, but the labour and organic-matter requirements are substantial (Roose et al., 1999). Half-moon trials show that water capture alone is not enough on nutrient-poor crusted soils because performance depends strongly on organic or mineral amendments (Zougmoré et al., 2003). The evidence supports integrated soil-water and fertility management rather than a single-structure solution.

Engineered systems present the opposite profile. They reduce household labour demands but require higher upfront investment, stronger site investigation, and more technical management (Okofo and Martienssen, 2022; Owusu et al., 2017). This makes them harder to scale widely without institutional backing. At the same time, where such backing exists, their returns can be substantial. Bhungroo Irrigation Technology requires an installation cost of about USD 10,000, but a single unit can irrigate 8–12 ha during the dry season, generate net returns of USD 5,000–10,000, and increase annual family incomes by more than 200% in the first year of operation (Owusu et al., 2017). This makes engineered recharge economically attractive in well-matched settings, even though its entry barrier is far higher than that of field-scale methods. The contrast is therefore not between cheap and expensive methods alone. It is between low-capital, high-labour options and high-capital, high-return systems that depend on strong technical and institutional support.

Maintenance requirements and operational sustainability

Maintenance requirements clearly distinguish the different intervention types. Field practices require repeated household labour, while reservoirs, boreholes, sand dams, and engineered recharge systems depend on organized inspection, finance, parts, and technical support. Studies in Builsa North and Jirapa identify inadequate funds, weak maintenance committees, limited operations capacity, transport problems, and scarce spare parts as major threats to rural water sustainability (Adeenze-Kangah, 2022; Osumanu et al., 2022). Reservoir sedimentation creates an additional long-term burden that routine minor repairs cannot solve (Adongo et al., 2020; Adwubi et al., 2009). Maintenance capacity is therefore a selection criterion, not an issue to address after construction.

Community applicability and governance fit

Community applicability adds another layer to the comparison. Some methods fit household decision-making, while others require collective rules, shared finance, and continuing institutional support. Evidence from 19 small-scale irrigation schemes in Northern Ghana shows that governance perceptions influence users’ willingness to contribute labour or funds to maintenance (Akuriba et al., 2022). Studies in Jirapa and Builsa North also show that committees without finance, training, spare-parts access, and continuing support struggle to sustain service (Adeenze-Kangah, 2022; Osumanu et al., 2022). The practical question is therefore not only whether a method is community managed, but whether the management arrangement has authority, resources, and technical support.

Environmental and livelihood co-benefits

Environmental and livelihood co-benefits also matter because long-term suitability is not determined by recharge effect alone. Agroforestry, mulching, residue retention, and related land-improvement measures support soil rehabilitation, erosion control, and livelihood value alongside hydrological improvement (Ilstedt et al., 2016; Nguru et al., 2026; Owuor et al., 2016; Winterbottom et al., 2013). This gives them strategic importance because they improve both water function and land condition. Structural and engineered methods may also produce co-benefits, but these are often narrower or more site-dependent. For this reason, the strongest long-term options are not always the ones with the largest immediate recharge effect, but the ones that improve hydrological function together with land productivity and resilience.

Overall comparative implications

The comparison therefore yields three intervention groups: broad-fit field methods (zaï pits, half-moons, bunds, stone lines, and soil cover), selective engineered methods (MAR, ASR, percolation structures, and sand dams), and biological complements (agroforestry and FMNR). Their suitability depends on labour, site conditions, finance, maintenance, water use, and tenure. Table 2 applies a consistent evidence and implementation framework to these groups.

Economically valuable agroforestry as a complementary solution

Agroforestry belongs in this discussion because groundwater recharge in Northern Ghana is constrained not only by immediate runoff loss, but also by the long-term degradation of soil structure and vegetation cover. This makes the recharge problem partly hydrological and partly ecological. Tree-based systems are relevant because they can improve infiltration pathways, stabilize soils, and support moisture retention while also generating economic value. Their place in the discussion is therefore not limited to conservation. Agroforestry matters because it connects hydrological improvement with farmer incentives, which is important in a context where long-term adoption depends on visible livelihood benefit.

The hydrological contribution of tree-based systems lies mainly in the way they improve the soil environment over time. Tree roots, litter input, and soil-structure improvement help create better conditions for infiltration, while root channels can support preferential flow pathways that allow water to move more effectively into the soil (Ilstedt et al., 2016). These functions are important in Northern Ghana because many recharge barriers are biological as well as physical. Degraded land does not only lose water because of slope or storm intensity. It also loses water because surface conditions have deteriorated to the point where rainfall is more likely to seal, run off, or be lost before it can infiltrate. In that sense, agroforestry strengthens recharge indirectly by improving the condition of the land through which water must pass.

At the same time, the effect of trees on recharge is not automatically positive in every form or at every density. The literature indicates that dense tree cover can increase transpiration enough to offset infiltration gains in some settings (Ilstedt et al., 2016). This means the recharge value of tree-based systems depends on balance rather than tree presence alone. Agroforestry supports recharge best when system design improves infiltration without creating excessive water use. This is an important point because it prevents agroforestry from being treated too simply. Trees are helpful, but their usefulness depends on the kind of tree system that is established and how it functions within the local water balance.

Economically valuable agroforestry systems are especially relevant for Northern Ghana, but local management context matters. A Northern Ghana study found that local tree-use and management practices can diverge from the strategies promoted by development organisations (Hansen et al., 2012). FMNR research in northeastern Ghana further shows that suitability and social equity depend on farmer preferences, available rootstock, land and tree tenure, authority, and whether fields are household controlled or communal (Kandel et al., 2021, 2022). Across 316 agroforestry plots in Ghana and Burkina Faso, land-use intensity and dispersal limitation also constrained regeneration, showing that suitable seed or root sources and protection from grazing matter for scaling FMNR (Lohbeck et al., 2020). Evidence from Niger links adoption with greater tree density, crop diversity, and household livelihood benefits, while also showing variation with soil type, market access, education, and local conditions (Haglund et al., 2011). Together, these findings support context-sensitive management rather than blanket tree-planting targets.

Even so, agroforestry also has practical limits. It can support livelihoods through products, land restoration, and improved farming conditions, which strengthens its place in a broader recharge strategy. However, benefits often take time to become fully visible, and uptake may remain weak where land tenure is insecure or where farmer support is limited (Kumar et al., 2015; Pasiecznik and Reij, 2020). This means the limits of agroforestry are not hydrological alone. They are also institutional. A farmer is less likely to invest in a long-term tree-based system if rights to land, trees, or future returns are uncertain. The practical strength of agroforestry therefore depends on whether the surrounding policy and support environment allows farmers to treat it as a worthwhile long-term investment (Nguru et al., 2026; Pasiecznik and Reij, 2020; Winterbottom et al., 2013).

For this reason, agroforestry is best treated as a complementary measure rather than a stand-alone recharge solution. Trees alone do not adequately control the rapid runoff generated by intense storms. Structural measures are still needed to slow and retain water near where it falls (Pasiecznik and Reij, 2020; Winterbottom et al., 2013). Agroforestry becomes most effective when those measures first create better opportunities for infiltration and the trees then reinforce long-term soil improvement (Pasiecznik and Reij, 2020). This complementary role fits Northern Ghana well. Structural measures respond to immediate runoff loss, while agroforestry addresses slower land rehabilitation and infiltration support. Together they provide a stronger and more balanced strategy than either approach would on its own (Partey et al., 2018; Winterbottom et al., 2013).

Policy considerations for implementation

Technical solutions alone are not enough to secure groundwater recharge in Northern Ghana because the success of recharge interventions depends not only on hydrological suitability, but also on governance, regulation, social acceptance, and long-term maintenance (Kwoyiga and Stefan, 2019). This is especially important in Northern Ghana, where many relevant interventions are implemented in shared landscapes, depend on communal structures, or require continued local upkeep. In such a context, technical feasibility does not automatically produce durable outcomes. A recharge structure may be physically appropriate, yet still fail if communities are not supported, if institutions are weak, or if responsibilities for management and maintenance remain unclear. The central policy challenge is therefore not simply how to introduce recharge technologies, but how to create the institutional conditions through strategic policies that provide financial and technical support to local communities that allow them to function over time.

This is where current policy support remains incomplete. Existing policies in Ghana provide some protection for water-related landscapes, but they do not yet amount to a direct recharge-focused strategy (Kwoyiga and Stefan, 2019). The Riparian Buffer Zone Policy and the National Environmental Policy help protect water bodies and require environmental assessment for water projects, which indirectly supports recharge-sensitive landscapes (Kwoyiga and Stefan, 2019). However, indirect support is not the same as deliberate recharge management. Protecting a water body does not by itself ensure that the surrounding land uses, watershed conditions, and infiltration zones that influence recharge are being actively managed for that purpose. If policy remains at the level of general environmental safeguards, recharge continues to be treated as a background process rather than as an explicit planning objective. Northern Ghana therefore needs policy that goes further by identifying recharge-sensitive zones, protecting valleys and headwaters, and managing land uses that influence infiltration.

The need for a more deliberate policy approach becomes clearer when community-scale recharge structures are considered. Such structures need more than local interest to succeed. Adoption and long-term sustainability are shaped by training, knowledge, group participation, and access to resources. Evidence shows that social group membership and training improve adoption of soil and water conservation practices, while financial support helps households overcome establishment barriers (Kwoyiga and Stefan, 2019; Pasiecznik and Reij, 2020). This means implementation cannot stop at identifying a suitable technique and promoting it to farmers or communities. Support must be built into the implementation process itself. Recharge structures are more likely to perform well when communities understand their purpose, participate in their management, and receive the technical and material support needed to maintain them. Without those conditions, even promising interventions risk remaining small, uneven, or short-lived (Kwoyiga and Stefan, 2019; Northern Patriots in Research and Advocacy (NORPRA), 2023; Pasiecznik and Reij, 2020).

The same logic applies to farmer adoption of soil and water conservation practices. Many recommended methods, especially zaï pits and structural runoff controls, require substantial labour or initial setup effort. Without support, adoption remains uneven and small in scale (Nguru et al., 2026; Roose et al., 1999). This makes incentives, training, and extension support central to implementation rather than secondary to it. These measures reduce the burden of adoption and help move recharge-related practices from isolated trials to wider use. The issue is not only whether a practice works in principle, but whether farmers can realistically adopt it within the labour, cost, and risk conditions they face. If policy ignores those conditions, it creates a gap between technical recommendation and actual uptake.

Agroforestry raises this issue even more sharply because it requires long-term investment. In northeastern Ghana, land and tree tenure shaped where and for whom farmer-managed natural regeneration was suitable, with household-controlled bush fields offering a stronger fit than communal land in many cases (Kandel et al., 2022). Policy should therefore align formal land administration with customary authority, with Lands Commission and District Assembly processes coordinated with customary landholders and traditional authorities to clarify land-use and tree-benefit rights, especially on communal land. Without secure expectations of future benefit, farmers have little reason to absorb the delayed costs of tree management.

Local governance arrangements are equally important because the sustainability of recharge-related infrastructure depends on who manages it, how responsibilities are enforced, and what support exists after construction. Studies in Builsa North and Jirapa show that nominal committees alone do not ensure sustainability when finance, training, spare parts, transport, and continuing support are weak (Adeenze-Kangah, 2022; Osumanu et al., 2022). Irrigation research likewise shows that governance perceptions affect cooperation in scheme maintenance (Akuriba et al., 2022). Recharge and storage interventions should therefore specify who owns the asset, who controls funds, who performs routine maintenance, how failures are reported, and which district or national institution provides technical backup.

All of this points to a larger issue in rural water planning. Groundwater recharge should be an explicit objective rather than a background assumption (Kwoyiga and Stefan, 2019). Local knowledge is also relevant to groundwater development: evidence from North East Ghana shows that irrigators use local knowledge strategically when locating and exploiting groundwater for dry-season production (Kwoyiga and Stefan, 2018). Recharge-oriented planning should therefore combine formal hydrogeological assessment with locally grounded information, while still moving from general mention of groundwater toward explicit provision for recharge enhancement (Kwoyiga and Stefan, 2019). Floodwater can then be treated not only as a hazard but as a potential resource for dry-season security (Owusu et al., 2017). Coordinated roles are required across agencies, District Assemblies, extension services, and local communities (Adams et al., 2024; Kwoyiga and Stefan, 2019).

Taken together, the evidence points to three major policy gaps in Northern Ghana. First, existing frameworks lack direct operational guidance for recharge-focused groundwater development (Kwoyiga and Stefan, 2019). Second, weak technical oversight has allowed poorly investigated and poorly designed infrastructure to underperform, as seen in dam failures linked to inadequate surveys and engineering practice (Northern Patriots in Research and Advocacy (NORPRA), 2023). Third, institutional fragmentation and weak support systems limit technology transfer and implementation (Kwoyiga and Stefan, 2019; Nguru et al., 2026). These gaps show that the main challenge is not the absence of possible interventions, but the absence of a strong policy framework that connects technical guidance, farmer support, local governance, and institutional coordination. A practical policy response therefore needs to combine formal recharge guidance, incentives for soil and water conservation, mandatory technical audits, and deliberate integration of customary governance into national planning. That kind of integrated approach is more consistent with the nature of the recharge challenge in Northern Ghana than treating each intervention as a separate solution.

A clearer division of institutional responsibility would make this framework more operational. The Water Resources Commission should lead groundwater regulation, recharge screening, water-quality safeguards, and performance monitoring. The Community Water and Sanitation Agency and District Assemblies should link rural water assets to funded maintenance and service monitoring. The Ghana Irrigation Development Authority should lead irrigation-reservoir planning and rehabilitation. Extension services should support contour layout, soil amendments, FMNR, and maintenance training, while Lands Commission processes, customary landholders, and traditional authorities clarify tenure and access. Gender evidence shows why inclusive monitoring matters. In Tatale-Sanguli, females were disproportionately affected by sporadic water supply (Jeil et al., 2020), while a mixed-method study of 394 women in East and West Mamprusi documented adverse effects of water scarcity on women’s non-agricultural livelihoods (Alhassan et al., 2024). A qualitative study in five Upper East communities further showed that women use local knowledge to negotiate access to land and wells and to sustain groundwater irrigation and household food security (Kwoyiga, 2024). These studies concern water access rather than recharge technologies, so intervention monitoring should record who supplies labour, participates in decisions, controls relevant land or assets, and receives dry-season water benefits.

Discussion

Synthesis of the review evidence

The reviewed evidence does not support a single-cause explanation of dry-season water insecurity in Northern Ghana. Recharge is limited and strongly seasonal, but the amount of water entering the subsurface is only one part of the problem. Whether that water becomes a dependable supply also depends on the location and connectivity of fractures, the thickness and storage capacity of weathered zones, the siting and condition of boreholes, the loss of reservoir capacity, and the institutions responsible for operation and repair. The central finding is therefore a combined explanation: rapid runoff and high evapotranspiration reduce the water available for storage, aquifer heterogeneity makes that storage unevenly accessible, and infrastructure and governance failures weaken the conversion of accessible water into reliable service.

This distinction changes how the intervention evidence should be interpreted. A method that increases infiltration does not automatically increase useful aquifer recharge, and a method that increases recharge does not automatically improve household water access. Table 1 shows that recharge estimates vary by aquifer, method, scale, and observation period. Table 2 shows that interventions also differ in directness of evidence, spatial applicability, labour, maintenance, cost, and institutional demand. Recommendations should therefore begin with diagnosis of the dominant local bottleneck rather than with predetermined technology.

The quantitative evidence illustrates both the magnitude of heterogeneity and the limits of aggregation. Across the eight recharge studies in Table 1, reported values span approximately 0.19–21.8% of annual precipitation at local, catchment, basin, or modelled scales, while several reported mean or long-term estimates fall near 6–9%. Infrastructure outcomes are also measurable: 24.2% of 115 assessed Tolon boreholes were defunct, northern reservoirs lost 8.54–34.12% of storage capacity, and all four small Upper East reservoirs in one study had lost their dead-storage capacity (Abdul-Ganiyu et al., 2022; Adongo et al., 2020; Adwubi et al., 2009). For land-surface interventions, 25 m stone-line spacing reduced runoff by 23% and doubled sorghum straw and grain yield in one Burkina Faso field experiment, while half-moons combined with organic amendments produced 900–1,600 kg/ha of sorghum, 20–39 times the yield reported for unamended half-moons (Zougmoré et al., 2000, 2003). These values are not pooled effect sizes; they show the range, directness, and endpoint of measured outcomes that underpin the comparative synthesis.

Controversies and trade-offs

Regional recharge potential and local groundwater accessibility are related but distinct. Basin and catchment estimates confirm that wet-season replenishment occurs, yet they combine locations with different weathered-zone thicknesses, fracture networks, lithologies, and hydraulic properties (Addai et al., 2016; Martin, 2006; Obuobie et al., 2012). This scale dependence is visible in contrasting estimates: a Ghana-wide water-balance model concluded that northern aquifers were sufficiently recharged for further development, whereas a Lawra groundwater-flow model estimated recharge at 3.6–16.4% of annual precipitation and Talensi modelling reported values near 2% (Anayah et al., 2013; Akurugu et al., 2020; Yidana et al., 2015). A community can therefore experience low borehole yield or seasonal failure even where a regional estimate appears moderate. The reverse is also true: a high local estimate from a favourable site cannot be treated as evidence of uniformly high groundwater potential across Northern Ghana. Regional recharge values are useful for broad planning, but borehole development and intervention design require local hydrogeological investigation.

A second debate concerns whether recharge is mainly diffused across the landscape or focused through channels, depressions, and flood-prone zones. High-resolution monitoring in crystalline-basement settings found that recharge was mainly diffuse and strongly influenced by antecedent soil moisture (Sorensen et al., 2024). Other studies and engineering proposals emphasize focused recharge from floodwater, river leakage, recharge basins, or managed aquifer recharge (Akurugu et al., 2020; Okofo and Martienssen, 2022; Owusu et al., 2017). These interpretations are not mutually exclusive. Diffuse recharge can sustain broad background replenishment, while focused recharge can be locally important where surface water is concentrated and connected to transmissive zones. The appropriate design question is not which mechanism applies everywhere, but which mechanism dominates at the proposed site and season.

Recharge limitation must also be separated from infrastructure and governance limitation. Increasing recharge will not restore a defunct pump, recover reservoir capacity lost to sediment, provide spare parts, or clarify responsibility for maintenance (Abdul-Ganiyu et al., 2022; Adongo et al., 2020; Adwubi et al., 2009). At the same time, stronger committees and financing cannot overcome an unsuitable aquifer, a poorly connected recharge zone, or a reservoir with an inadequate catchment. Physical and institutional explanations should therefore be treated as interacting constraints rather than competing alternatives. The practical objective is to identify whether a site is limited mainly by source water, aquifer access, storage, infrastructure condition, management, or a combination of these factors.

The hydrological role of trees presents another important trade-off. Agroforestry and farmer-managed natural regeneration can improve litter cover, soil structure, roughness, and root pathways, which supports infiltration and land restoration (Haglund et al., 2011; Kandel et al., 2022). Yet greater tree cover also increases transpiration, and the recharge benefit may decline where tree density or species water use becomes too high. Evidence that intermediate tree cover can maximize recharge illustrates why both tree absence and excessive density can be unfavourable (Ilstedt et al., 2016). Agroforestry should therefore be designed around suitable species, density, field context, and livelihood value rather than promoted under the assumption that more trees always produce more recharge.

Distributed restoration and engineered recharge serve different purposes. Field measures can reach many farms and improve erosion control, root-zone moisture, and livelihoods, but their effects on deep recharge are indirect. MAR and ASR target identified storage zones more deliberately but have narrower applicability and higher technical, financial, water-quality, and regulatory demands (Kwoyiga and Stefan, 2019; Okofo and Martienssen, 2022; Owusu et al., 2017). A portfolio approach therefore uses distributed measures for widespread land-surface losses and engineered recharge where subsurface storage is demonstrably feasible.

The apparent conflict between regional averages and fractured-aquifer variability is partly a matter of scale. Regional averages help identify the overall magnitude and seasonality of recharge, but they can conceal sharp differences between adjacent wells and communities. Fractured and weathered aquifers are especially sensitive to local structure and borehole placement, and different recharge methods introduce additional uncertainty (Afrifa et al., 2017; Akurugu et al., 2020; Obuobie et al., 2012; Yidana and Koffie, 2014). Policy should therefore use regional estimates for strategic planning and local measurements for siting, design, abstraction limits, and performance evaluation. A nested monitoring approach is more defensible than relying on either regional averages or isolated local values alone.

These trade-offs explain why the qualitative ratings in Table 2 should not be read as a fixed regional ranking. Overall fit depends on the bottleneck being addressed, the landscape position, aquifer conditions, labour availability, tenure, maintenance arrangements, and the level of institutional support. The strongest option at one site may be inappropriate at another. The purpose of comparison is to guide conditional selection, not to declare one universal solution.

Research gaps and implementation limits

The review also highlights an important difference between farm-scale feasibility and watershed-scale opportunity. At the farm scale, methods that households can implement, control, and maintain directly are likely to be more durable because decision-making and benefit remain closely linked. This strengthens the case for field-based runoff harvesting and soil-improvement measures as the entry point for wider adoption. At the watershed or community scale, however, hydrological opportunity may increase because water can be intercepted and managed across broader shared terrain, but so do the demands for coordination, maintenance, and accountability. This helps explain why some larger communal or engineered interventions remain attractive in theory but vulnerable in practice. Their success depends not only on hydrological design, but also on whether collective institutions are strong enough to sustain them.

Another important insight is that infiltration support and recharge are not identical goals. Agroforestry shows this clearly. Tree-based systems can improve litter input, root activity, and soil structure and can create conditions that favour infiltration (Ilstedt et al., 2016). They also offer livelihood value through economically useful systems such as shea parklands, FMNR, and orchard-based approaches (Pasiecznik and Reij, 2020; Winterbottom et al., 2013). Yet the review also shows that tree cover is not an unlimited hydrological good. Dense tree cover may increase transpiration enough to offset infiltration gains in some settings (Ilstedt et al., 2016). This means agroforestry should not be interpreted as a stand-alone recharge solution. Its strength lies in long-term land rehabilitation and complementary support to structural runoff-control measures rather than in replacing them. This is a useful reminder that methods that improve land condition do not always produce the same outcome as methods designed specifically to capture or store water.

A recurring limitation is the tendency to treat technical suitability as sufficient. Evidence from small dams and recharge governance shows that weak siting, design, maintenance, and institutional responsibility can undermine otherwise plausible interventions (Kwoyiga and Stefan, 2019; Northern Patriots in Research and Advocacy (NORPRA), 2023). Long-term performance therefore requires institutional as well as hydrological realism.

Limitations of the review

This review has four important limitations. First, it is a structured critical narrative review rather than a systematic review; no protocol was preregistered and no formal risk-of-bias instrument was applied. Targeted searching and author judgement may therefore leave residual selection bias despite the use of multiple search platforms, explicit eligibility criteria, reference-list checking, and qualitative evidence appraisal. Second, the evidence base is heterogeneous in method, scale, outcome, and geography, which precludes defensible pooled effect sizes. Third, several intervention conclusions rely on transferable evidence from Burkina Faso, Niger, Kenya, or broader drylands because long-term Ghana-specific field measurements are limited; such evidence was treated as supportive rather than equivalent to local validation. Fourth, the 2011–2025 NASA POWER series provide recent descriptive climatology at fixed points and cannot establish long-term climate trends or future change. An additional workflow limitation is that record-level search and screening counts were not preserved contemporaneously during the original narrative review. The August 2026 verification rerun was therefore used to reconstruct a transparent audit trail rather than to assign unverifiable historical counts to the earlier searches.

Dedicated Northern Ghana studies document gendered burdens of sporadic water supply and water scarcity (Alhassan et al., 2024; Jeil et al., 2020), but intervention-performance studies still rarely report gender-disaggregated effects, distributional equity, or political-economy incentives surrounding new construction versus maintenance. This limits conclusions about how labour burdens, control of land and assets, decision-making authority, and benefits are distributed among users. Climate modelling also indicates non-stationary hydrological conditions. One West African simulation projected potential recharge in Northern Ghana to increase from about 5% to about 10% of rainfall under its RCP8.5 scenario, while Volta-basin modelling found scenario-dependent and spatially contrasting changes in rainfall and water availability (Cook et al., 2022; Dembélé et al., 2022). The present review does not independently quantify future recharge. Future studies should therefore report disaggregated access and decision-making outcomes and stress-test intervention performance under plausible changes in rainfall intensity, dry-spell duration, and evaporative demand.

Potential developments in the field

The most useful development for the field is a shift from technology-first planning to bottleneck-first planning. Assessment should begin by asking what prevents dependable dry-season service at a specific location. A failed but hydrologically viable borehole requires rehabilitation and maintenance reform. Runoff-prone cultivated slopes may justify contour bunds or stone lines. Crusted and severely degraded plots may justify zaï pits or half-moons with soil amendments. Areas with suitable seasonal channels may justify investigation of sand dams, while flood-prone areas above suitable aquifers may justify monitored recharge-basin, MAR, or ASR pilots. This decision sequence aligns the intervention with the mechanism of failure rather than assuming that every water-security problem is primarily a recharge deficit.

Future research should support this approach through nested monitoring that connects rainfall, soil moisture, runoff, recharge, aquifer response, infrastructure performance, and household service. Comparative field trials should report not only infiltration or crop response, but also maintenance demand, labour, costs, equity, water quality, sample size, uncertainty, and persistence over several seasons. Engineered pilots should include baseline hydrogeology, source-water quantity and quality, recovery efficiency, clogging, groundwater-level response, water-quality safeguards, and clear institutional responsibility. These data would allow future syntheses to move beyond qualitative fit categories toward evidence-weighted decision rules for different northern landscapes.

Practical recommendations

Recommendations should follow a diagnostic sequence rather than a single regional ranking. The first step is to determine whether the immediate constraint is failed infrastructure, low local groundwater accessibility, rapid runoff, degraded soil, inadequate surface storage, weak management, or several of these together. Table 2 shows that each intervention addresses a different part of the problem and carries different demands for labour, maintenance, finance, land, and institutional capacity.

Where existing boreholes and reservoirs remain hydrologically viable, rehabilitation can be the fastest route to restore service because it works with assets that already exist rather than assuming that new construction is required. Borehole repairs, pump replacement, desilting, spillway and embankment repair, spare-parts systems, and routine inspection should precede unnecessary new construction where technical diagnosis confirms continued viability (Abdul-Ganiyu et al., 2022; Adongo et al., 2017, 2020; Adwubi et al., 2009). Repeated repair is not justified where borehole siting, aquifer yield, dam catchment, or structural design is fundamentally unsuitable. Maintenance finance and responsibility must be established at the same time so that restored systems do not return to failure.

Distributed runoff-control measures should be selected by landscape condition. Contour bunds and stone lines are appropriate on gently sloping cultivated land where runoff concentration, contour layout, stone supply, and periodic repair are manageable (Tefera et al., 2024; Zougmoré et al., 2000, 2002). Zaï pits are best targeted to severely crusted or degraded small plots where households have sufficient labour and organic inputs, while half-moons are more suitable for larger restoration patches where captured water is combined with fertility amendments (Roose et al., 1999; Zougmoré et al., 2003). Mulch, manure, compost, and residue cover should support these structures where biomass opportunity costs allow. These measures should not be presented as proven deep-recharge technologies. Their strongest evidence concerns runoff reduction, soil-water storage, erosion control, vegetation recovery, and crop performance.

Agroforestry and FMNR should be added where farmer preferences, rootstock, species choice, tree density, and land and tree tenure support long-term management (Haglund et al., 2011; Kandel et al., 2022). Their role is complementary: they improve soil condition, provide products and livelihood incentives, and support infiltration over time. Current evidence does not justify one universal species or tree-density prescription for Northern Ghana. Locally established systems such as shea-based parklands and FMNR should therefore be managed adaptively, using locally valued species or rootstock and densities that preserve crop access while avoiding excessive transpiration; monitoring should track soil moisture, crop response, and dry-season water use (Ilstedt et al., 2016; Kandel et al., 2022). Tenure arrangements and benefit rights should be resolved before programmes ask farmers to make long-term tree investments.

Sand dams, percolation ponds, recharge basins, MAR, and ASR should be treated as selective engineering options. Sand dams require suitable seasonal channels, sediment characteristics, foundations, abstraction points, and community management (Lazurko et al., 2024; Ritchie et al., 2021, 2023). Before recharge-basin, MAR, or ASR pilots proceed, screening should establish the seasonal volume and timing of source water, aquifer storage and transmissivity, unsaturated-zone permeability and hydraulic connection, baseline groundwater and source-water quality, contamination and clogging risks, land and energy requirements, and the institution responsible for operation. Ghana-specific work on MAR site selection in granitic aquifers reinforces the need for site-specific hydrogeological evaluation before implementation (Acheampong et al., 2024), alongside Northern Ghana feasibility and modelling evidence (Kwoyiga and Stefan, 2019; Okofo and Martienssen, 2022; Owusu et al., 2017). Pilot monitoring should include recharge volume, infiltration performance, groundwater-level response, water quality, recovery efficiency where applicable, maintenance demand, and dry-season service.

Policy and governance should support the full intervention sequence. Government and development partners should require hydrogeological and subsoil investigation before new infrastructure, publish maintenance and performance responsibilities, and provide practical guidance for recharge-focused planning. Community institutions should have defined authority, transparent finance, access to repair services, and inclusive participation. Land and tree tenure require attention wherever structural conservation or agroforestry depends on long-term household investment (Adeenze-Kangah, 2022; Akuriba et al., 2022; Kandel et al., 2022; Kwoyiga and Stefan, 2019; Osumanu et al., 2022). Monitoring should evaluate dependable dry-season service, distribution of benefits, maintenance, and water quality alongside hydrological performance.

The resulting order of action is conditional rather than universal. Diagnose the bottleneck first. Restore viable existing assets where service failure is the immediate problem. Apply field-scale runoff control and soil restoration where land-surface losses dominate. Add agroforestry and FMNR where tenure and tree-management conditions are favourable. Investigate sand dams or recharge basins where channel and aquifer conditions justify them. Use MAR and ASR only after detailed site investigation and institutional preparation. This approach follows the evidence in Tables 1, 2 and avoids treating one intervention as the default for every northern landscape.

Concluding synthesis

Dry-season water insecurity in Northern Ghana cannot be reduced to insufficient rainfall or recharge failure alone. It results from the interaction of limited and highly seasonal effective recharge, rapid runoff and high evapotranspiration, uneven access to fractured and weathered aquifers, loss or failure of surface and groundwater infrastructure, and maintenance, financing, governance, and land-tenure constraints. Recharge estimates describe how much water enters the subsurface under particular conditions, but they do not by themselves show whether that water is accessible, safely stored, or converted into dependable community service.

The intervention evidence therefore supports a site-specific portfolio rather than one broad-fit package. Rehabilitation is the immediate priority where existing boreholes and reservoirs remain viable. Contour bunds and stone lines fit runoff-prone cultivated slopes, while zaï pits and half-moons fit more severely crusted and degraded areas with adequate labour and fertility inputs. Soil cover, agroforestry, and FMNR strengthen land condition and livelihoods where biomass and tenure constraints are addressed. Sand dams, recharge basins, MAR, and ASR remain valuable options at selected sites, but their use depends on hydrogeological suitability, source-water quality, finance, monitoring, and institutional capacity.

This portfolio also clarifies the relationship between distributed restoration and engineered recharge. Distributed measures offer broad landscape reach and multiple agricultural benefits, but their contribution to deep aquifer storage is indirect and variable. Engineered systems offer more deliberate storage at suitable sites, but have narrower applicability and greater technical and governance demands. The strongest strategy combines these roles without assuming that either one replaces the other.

The synthesis yields four management implications. First, recharge, abstractable groundwater, and water security should be evaluated as distinct stages of the rainfall-to-service chain. Second, intervention selection should follow the dominant local bottleneck rather than a fixed technology hierarchy. Third, evidence directness matters: runoff reduction, soil-moisture improvement, or crop response should not be interpreted as demonstrated deep aquifer recharge unless subsurface response was measured. Fourth, operation, maintenance, and governance are not downstream implementation details; they are part of intervention performance itself. These insights convert the reviewed technologies into a diagnostic framework for selecting and evaluating water-security investments.

The practical priority is to match the intervention to the dominant local bottleneck and to judge success by reliable, equitable dry-season water service. This requires local hydrogeological investigation within regional planning, rehabilitation linked to durable maintenance systems, field measures matched to slope and soil condition, tenure-sensitive land restoration, and monitored engineering pilots. Northern Ghana will improve water security not through one technology, but through coordinated decisions that connect rainfall partitioning, aquifer accessibility, infrastructure reliability, and institutional responsibility.

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Supplementary material

The Supplementary material for this article can be found online at: https://www.frontiersin.org/articles/10.3389/frwa.2026.1948902/full#supplementary-material

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Footnotes

Edited by: Giulio Castelli, University of Florence, Italy

Reviewed by: Evans Asenso, University of Ghana, Ghana

Kifle Woldearegay, Mekelle University, Ethiopia