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Although many studies have assessed the singular impacts of future land use and climate change on river hydrology, few studies have investigated the distinct and combined impacts of land use and climate change on river flows particularly in developing countries faced with a challenge of limited data. This study addressed the aforementioned gap and applied the Soil and Water Assessment Tool and an ensemble of six CORDEX Regional Climate Models under the moderate (RCP4.5) and high (RCP8.5) emission scenarios in the river Rwizi catchment area in western Uganda for the period 2021–2050. The isolated impacts of land use change and the combined impacts showed an increase in future total annual river flows. However, the isolated impacts of climate change showed a reduction in future total annual flow. The influence of land use changes on total annual runoff was more dominant than that of climate change. The results show that climate change is the dominant factor impacting future high-flow quantiles while future annual flow and extreme low-flow variations were attributed mainly to land use changes. These findings point to the need to plan and implement prudent land use and water resource management practices to mitigate associated risks. HIGHLIGHTS Distinct and combined future climate and land use change impacts were assessed.; Trend analyses highlight the major contributors to the changes in future river flow.; This study sheds light on the performance of reanalysis datasets in data-scarce areas like the river Rwizi catchment.; This study informs the need to implement pragmatic catchment management strategies to accelerate progress towards Sustainable Development Goal 6.4–6.6.;

Limited research has been undertaken on significant factors associated with transitions between drinking water supply systems (DWSS) ladders. In this paper, we applied panel ordered logistic multinomial logistic regression models to seven datasets of the Uganda Demographic and Health Survey (1988–2021), with the SDG6 categorical levels of DWSS (unimproved, improved and piped into dwelling) as transition levels, and various socio-economic and demographic characteristics as covariates. Sex and education level of household head, toilet facility, electricity access, size of agricultural land and wealth index are significant factors. The main implication is the need to address socio-economic disparities in developing economies. HIGHLIGHTS Sheds light on significant factors associated with transitions between drinking water supply systems ladders.; Informs the need to address socio-economic disparities to transition between drinking water service systems.; Several factors are associated with the transition of drinking water service systems.; Points to the need to address the socio-economic attribute disparity to accelerate options transitions.;

This study explored the combined impacts of climate and land-use change on mini-hydropower generation in the Kyambura watershed. The soil and water assessment tool (SWAT) was used as a hydrological model whereas the statistical downscaling model (SDSM) was used to downscale meteorological data for the Kyambura watershed for the year 2050. The results show that there will be an increase in urban land by 11.89%, barren land by 25.78%, water by 0.49% and a reduction in percentage area coverage of vegetation by 38.17% by the year 2050. A 10.6 and 17.7% increase is anticipated in average annual hydropower generated by the year 2050. There is, therefore, a need to develop governing policies to regulate management practices to preserve the integrity of the watersheds and ensure the reliability of power production. HIGHLIGHTS Quantifies LULC changes within the Kyambura catchment from 1989 to 2019.; Predicts and quantifies LULC changes within the Kyambura catchment by the year 2050.; Predicts the changes in climate, stream flows and Hydropower generation within the Kyambura catchment by the year 2050.; Elucidates on the impacts of climate and Land use/cover change on mini-hydropower generation.;

Statistical models can be used as proactive approaches to pipe failure management for the satisfactory and efficient functionality of a water distribution network (WDN). The study aimed to develop two logistic regression models using historical data and evaluated them based on prediction accuracy, receiver operator characteristics (ROC), and area under the curve (AUC). Pipe sizes ranging from 150 mm to 350 mm in the WDN were adequate to prevent pipe failure. However, a 250 mm pipe diameter had the lowest failure probability. Old pipes had a lower failure probability than new pipes. Although it was evident that the installation design of water pipes is changing from steel to unplasticized polyvinyl chloride (uPVC), steel pipes had a lower failure probability than uPVC at the same depth from the soil surface. Pipes buried in gravel with a small diameter had a lower failure probability than those in clay of a bigger diameter. With a median pipe age of 8 years in the WDN and greater class weight on pipe failures, the binomial logistic regression model had better performance (accuracy – 96.9%, AUC – 0.996) than the multinomial logistic model (accuracy – 90.9%, AUC – 0.992), representing reliable model predictions. The models can be used to modify data collection protocols to better identify potential water pipes that require maintenance or replacement. HIGHLIGHTS Pipe failure is intricate and depends on physical, environmental, and operational pipe attributes.; 250-mm pipe diameter had the lowest failure probability.; Old pipes have a lower failure probability than new pipes.; Pipes with low population density had a higher failure probability than those in densely populated areas.; Binomial logistic regression model had better performance than the multinomial logistic model.;

Hydraulic ram (hydram) pump has been in existence for more than two centuries. However, these pumps have been on the verge of extinction since the invention of motorized pumps, which are more powerful and efficient. Unfortunately, motorized pumps are expensive to acquire, operate, and maintain. Their contribution to climate change and environmental degradation has steered the need for an alternative pumping technology. Therefore, as the world's technology shifts to green energy, hydram pumps need to be re-invented. In the late twentieth century, studies on hydram pumps have been revived with the aim of making them more efficient and economically competitive. Small-scale farmers in West Pokot County, Kenya, have embraced the hydram technology, but due to low technical capacity; installed low-performing hydram that operated under low efficiencies of less than 30%, with the majority having operational failure due to inadequate designs. Hence, this study investigated the design and operation of these pumps. Thereafter, designed and assembled a hydram pump, using locally available materials, to supply water for domestic and small-scale agricultural use. The optimum efficiency achieved by the pump was 54%, with an optimum delivery flow rate of about 13 L/min. HIGHLIGHTS The locally installed hydraulic ram pumping system performs way below its potential due to low technical know-how.; The study assesses the performance, thereafter, designs a prototype pump that can cheaply be fabricated by local farmers for irrigation.; The fabricated pump exhibits higher efficiency compared to the existing hydraulic ram pumping systems.; The study aims to make the pump economically competitive.;

Data scarcity has been a huge problem in modelling catchments especially in the tropical region. Satellite data and different statistical methods are being used to improve the quality of conventional meteorological data. However, their potential needs to be further investigated. This paper evaluates the performance of three datasets in simulating discharge of River Manafwa, Uganda. Two reanalysis datasets were selected for studying both rainfall and temperature, whereas a satellite algorithm was selected for studying rainfall alone. MERRA-2 data and CFSR were chosen as the reanalysis datasets whereas TRMM3B42 data were used as the satellite product in this study. The SWAT model was used to evaluate the performance of these datasets. The model performance indicators indicated that, at daily time steps, all the three datasets produced values of Nash -Sutcliffe Efficiency (NSE

Introduction: Faecal sludge management (FSM) in urban areas of low-and middle-income countries (LMICs) is not properly implemented due to inaccessibility of sanitation facilities and high faecal sludge (FS) emptying costs, amongst others. Unlike in solid waste and fresh human excreta, use of black soldier fly larvae (BSFL) in treatment of FS from pit latrines - which are the most common sanitation facilities in urban areas of LMICs - has not yet been explored. Moreover, the optimal conditions for efficient FS degradation, such as moisture content, feeding rate and larval density are not yet well known. Against this backdrop, the overarching aim of this study was to determine the effectiveness of BSFL in treating FS under different conditions of moisture content, feeding rate and larval density. Also, the quality of residue left after treatment was assessed.Methods: FS samples were collected from lined and unlined pit latrines in Bwaise I parish in Kampala, Uganda and experiments were set up to feed 10-day old larvae.Results and Discussion: The optimum feeding rate, larval density and moisture content were found to be 50 mg/larvae/day, 1.33 larvae/cm2 and 60%, respectively. The reduction efficiency at optimum conditions were 72% and 66% for FS from lined and unlined pit latrines, respectively. It was further noted that BSFL can feed on FS from pit latrines without dewatering it, hence there is no need for a dewatering unit. The properties of the residue left after treatment were within the allowable limit for use as compost except for helminth egg concentration. Thus, in informal urban settlements, BSFL can be applied for effective treatment of FS from pit latrines while generating good quality residue thereby providing an additional value chain in FSM.

Ugandan rivers are being tapped as a resource for the generation of hydropower in addition to other uses. Studies on the reliability of these hydropower plants due to climate and land-use/land cover changes on the hydrology of these rivers are scanty. Therefore, this study aimed to model the impact of the changing climate and land-use/cover on hydropower reliability to aid proper planning and management. The hydropower reliability of Muzizi River catchment was determined from its past (1998–2010) and midcentury (2041–2060) discharge at 30 and 95% exceedance probability under Representative Concentration Pathways (RCPs) of 4.5 and 8.5, respectively. The past and projected hydropower were compared to determine how future climate and land-use changes will impact the discharge and hydropower reliability of Muzizi River catchment. Six LULC scenarios (deforestation, 31–20%; grassland, 19–3%; cropland, 50–77%; water bodies, 0.02–0.01%; settlement, 0.23–0.37%, and Barren land 0.055–0.046% between 2014 and 2060) and three downscaled Regional Climate Model (REMO and RCA4 for precipitation and RACMO22T for temperature from a pool of four CORDEX (Coordinated Regional Climate Downscaling Experiment) Africa RCMs) were examined. A calibrated SWAT simulation model was applied for the midcentury (2041–2060) period, and a potential change in hydropower energy in reference to mean daily flow (designflow ≥ 30% exceedance probability), firm flow (flow ≥ 95% exceedance probability), and mean annual flow was evaluated under the condition of altered runoff under RCP4.5 and RCP8.5 climate change scenarios for an average of REMO and RCA4 RCM. The future land use (2060) was projected using the MOLUSCE (Module for Land Use Change Evaluation) plugin in QGIS using CA-ANN. Three scenarios have been described in this study, including LULC change, climate change, and combined (climate and LULC change). The results suggest that there will be a significant increase in annual hydropower generation capacity (from 386.27 and 488.1 GWh to 867.82 and 862.53 GWh under RCP4.5 and RCP8.5, respectively) for the combined future effect of climate and land-use/cover changes. Energy utilities need to put in place mechanisms to effectively manage, operate, and maintain the hydropower plant amidst climate and land-use change impacts, to ensure reliability at all times. HIGHLIGHTS Innovative approaches for hydrological modeling in data-scarce scenarios.; The possibility to utilize bias-corrected reanalysis and historical discharge data to build a climate model in data-scarce scenarios.; Sheds light on the potential risks of land-use and climate change on hydropower reliability in data scarcity areas.; Informs the need to implement prudent catchment management practices and develop policies.;

The unprecedented outbreak of COVID-19 necessitated the promotion of better hygiene practices to curb the spread of the virus. Better hygiene requires that households have a stable supply of water. However, little is known about the predictors of changes in water use in emergency situations such as COVID-19 in Uganda. This study uses data from a cross-sectional survey to examine the changes in the quantities of water used by 1,639 Ugandan households due to COVID-19. This article also explores the factors that are associated with changes in water use. The month March 2020 is used in this study as a cut-off because this is the month in which the government implemented a lockdown to curb the spread of the virus. Results indicate that most households had an increase in the quantity of water used after March 2020 when compared with the period before March 2020. Household characteristics that were associated with a change in the quantity of water used were age, sex, education, main occupation of household head, household size and region of residence. The results can be used to inform the prediction and demand modelling of household water use for improved water interventions for equitable water supply during emergencies. HIGHLIGHTS About 2.1 billion people worldwide lack access to clean water for household use.; The outbreak of COVID-19 emphasises the need to improve hygiene as a behavioural strategy.; Households changed behaviour due to COVID-19 which increased water use after March 2020 when compared with the period before March 2020.; There is need to design interventions to cope with the challenges for increased demand for water during emergencies.;

Abstract Many regions globally are grappling with the challenge of recurrent extreme weather events. Whereas attempts are being undertaken to understand their characteristics as a first step to guide targeted mitigation measures, these are focused on dryness and not wetness, which is also a challenge in sub‐humid areas. This study investigates dryness and wetness characteristics using the standardized precipitation evaporation index (SPEI) at timescales of 3, 6, 12 and 24 months for a period of 1901–2018 across Uganda's drainage basins. Trends in the dryness and wetness evolutions were conducted using the Mann‐Kendall (MK) statistic to establish the effects of global warming on the study area. A step change analysis reveals 1961 as a change point year from cool to warm periods. Results also reveal that warming mainly occurred in the recent period (1962–2018), with a temperature rise of over 2οC being recorded in 2009. Severe dryness events occurred in the recent period as opposed to wetness events that dominated the earlier period (1901–1961). Dryness and wetness varied among drainage basins, with the Aswa basin being more susceptible to severe dryness while the Lake Kyoga basin to severe wetness. Lira and Kitgum were identified as drought hotspots at timescales of 3, 6 and 12 months. SPEI was able to reveal 60% of historical dryness events and 75% of wetness events on record, making it an adequate tool for monitoring humid events as opposed to droughts in sub‐humid climates. It is hoped that this evidence can guide targeted mitigation measures towards climatic shocks within the region.

With the emergence of COVID-19, improving hygiene through handwashing with water and detergent is a priority. This behavioural practice requires that households have access to reliable improved water. One measure that can provide an invaluable source of information to measure access to improved water supply is willingness to pay (WTP). However, little is known about WTP for water during a pandemic such as COVID-19. Data from a cross-sectional survey was used to assess potential household determinants of WTP for water during March-June 2020 in 1639 Ugandan households. The focus is on the period March-June 2020 when the government of Uganda implemented a countrywide total lockdown in a bid to curb the spread of the deadly virus. Results indicate that most households were not willing to pay for water during March-June 2020. Sex of the household head, region of residence, water source, number of times hands are washed and whether a household buys or pays for water were significant explanatory household determinants for WTP for water. The results provide a rich understanding of the household factors that determine WTP for water during a pandemic. This evidence is important in guiding government and water utilities in developing sustainable regulations and policy interventions particularly during emergencies. The findings suggest that increasing or maintaining water revenues will be a challenge in emergencies if no attention is placed to addressing the disparity in socio-economic attributes associated with households’ WTP.