Small reservoirs in Africa: a review and synthesis to strengthen future investment

Small reservoirs are a critical coping mechanism in water-stressed rural areas in Africa, providing immense livelihood benefits that include improved food and water security, entrepreneurial activities and climate resilience. Challenges associated with the implementation of investments in small reservoirs include appropriate site selection, weak institutions, insufficient maintenance and sedimentation. The findings from this study suggest that the benefits of small reservoirs may be tapped more efficiently by rehabilitating old sites rather than building new infrastructure. However, the findings also point to broader lessons on the need to change the way of doing business, i.e., to adopt a long-term, more holistic approach (or model) to the construction and maintenance of small reservoirs that matches the degree of the challenge associated with sustainably tapping the benefits of the water that they store

Malaria transmission in the vicinity of impounded water: evidence from the Koka Reservoir, Ethiopia

Malaria / Waterborne diseases / Disease vectors / Habitats / Disease control / Entomology / Epidemiology / Surveys / Dams / Reservoirs / Villages / Case studies / Africa / Ethiopia / Koka Reservoir / Rift Valley / Awash River Basin

Malaria around large dams in Africa: effect of environmental and transmission endemicity factors.

BACKGROUND:The impact of large dams on malaria has received widespread attention. However, understanding how dam topography and transmission endemicity influence malaria incidences is limited. METHODS:Data from the European Commission's Joint Research Center and Shuttle Radar Topography Mission were used to determine reservoir perimeters and shoreline slope of African dams. Georeferenced data from the Malaria Atlas Project (MAP) were used to estimate malaria incidence rates in communities near reservoir shorelines. Population data from the WorldPop database were used to estimate the population at risk of malaria around dams in stable and unstable areas. RESULTS:The data showed that people living near (< 5 km) large dams in sub-Saharan Africa grew from 14.4 million in 2000 to 18.7 million in 2015. Overall, across sub-Saharan Africa between 0.7 and 1.6 million malaria cases per year are attributable to large dams. Whilst annual malaria incidence declined markedly in both stable and unstable areas between 2000 and 2015, the malaria impact of dams appeared to increase in unstable areas, but decreased in stable areas. Shoreline slope was found to be the most important malaria risk factor in dam-affected geographies, explaining 41-82% (P < 0.001) of the variation in malaria incidence around reservoirs. CONCLUSION:Gentler, more gradual shoreline slopes were associated with much greater malaria risk. Dam-related environmental variables such as dam topography and shoreline slopes are an important factor that should be considered in efforts to predict and control malaria around dams

The devil’s in the details: data exchange in transboundary waters

Data exchange in transboundary waters is fundamental to advance cooperative water management. Nonetheless, the degree to which data are shared is not well understood. To gauge this degree, an assessment framework was developed and applied in 25 international river basins. The framework captures the degree to which a set of data parameters is exchanged among countries. A reasonable proportion of surveyed basins exchange some data, but the breadth of such exchange is often limited, and not regular. This paper highlights where data exchange can be improved and provides guidance on how indicators used in global assessment frameworks can motivate this improvement

Sustainable WEF Nexus Management : A Conceptual Framework to Integrate Models of Social, Economic, Policy, and Institutional Developments

Funding Information: This work was supported by the Decision Analytic Framework to explore the water-energy-food nexus in complex transboundary water resource systems of fast developing countries (DAFNE) project, which has received funding from the European Union's Horizon 2020 research and innovation program under grant Agreement No. 690268.Peer reviewedPublisher PD

Resilience in the Limpopo Basin : The potential role of the transboundary Raotswa aquifer - Final draft

As complementary report of the baseline report, this report focus on the hydrogeological assessment of the Ramotswa Transboundary Aquifer and covers only aspects related to the biophysical conditions of the aquifer which is a karstic dolomit aquife straddling the international border between Botswana and South Africa. The assessment is based on existing data and field data collected (including Airborne Electro-Magnetic survey) during the period September 2015 –November 2016. The technical knowledge developed in the report will be used as based for developing tools for harmonized management and fostering crossborder dialogue in order to help building the joint Strategic Action Programme which will provide, not exclusively, guidelines for better monitoring and future assessment of the aquifer

A scale-based framework to understand the promises, pitfalls and paradoxes of irrigation efficiency to meet major water challenges

An effective placement of irrigation efficiency in water management will contribute towards meeting the pre-eminent global water challenges of our time such as addressing water scarcity, boosting crop water productivity and reconciling competing water needs between sectors. However, although irrigation efficiency may appear to be a simple measure of performance and imply dramatic positive benefits, it is not straightforward to understand, measure or apply. For example, hydrological understanding that irrigation losses recycle back to surface and groundwater in river basins attempts to account for scale, but this generalisation cannot be readily translated from one location to another or be considered neutral for farmers sharing local irrigation networks. Because irrigation efficiency (IE) motives, measures, effects and technologies play out at different scales for different people, organisations and purposes, and losses differ from place to place and over time, IE is a contested term, highly changeable and subjective. This makes generalisations for science, management and policy difficult. Accordingly, we propose new definitions for IE and irrigation hydrology and introduce a framework, termed an ‘irrigation efficiency matrix’, comprising five spatial scales and ten dimensions to understand and critique the promises, pitfalls and paradoxes of IE and to unlock its utility for addressing contemporary water challenges

A scale-based framework to understand the promises, pitfalls and paradoxes of irrigation efficiency to meet major water challenges

An effective placement of irrigation efficiency in water management will contribute towards meeting the pre-eminent global water challenges of our time such as addressing water scarcity, boosting crop water productivity and reconciling competing water needs between sectors. However, although irrigation efficiency may appear to be a simple measure of performance and imply dramatic positive benefits, it is not straightforward to understand, measure or apply. For example, hydrological understanding that irrigation losses recycle back to surface and groundwater in river basins attempts to account for scale, but this generalisation cannot be readily translated from one location to another or be considered neutral for farmers sharing local irrigation networks. Because irrigation efficiency (IE) motives, measures, effects and technologies play out at different scales for different people, organisations and purposes, and losses differ from place to place and over time, IE is a contested term, highly changeable and subjective. This makes generalisations for science, management and policy difficult. Accordingly, we propose new definitions for IE and irrigation hydrology and introduce a framework, termed an ‘irrigation efficiency matrix’, comprising five spatial scales and ten dimensions to understand and critique the promises, pitfalls and paradoxes of IE and to unlock its utility for addressing contemporary water challenges