Factors Influencing Water Resources Availability And Water Use Efficiency:Evidence From Sub-Saharan Africa

The availability and efficient use of water resources play a significant role in ensuring adequate access to water resources for all,but this has been a grey area of research in sub-Saharan Africa.For that reason,this study seeks to investigate factors that affect the availability and efficient use of water resources within sub-Saharan Africa.Forty-one countries in sub-Saharan Africa were selected to examine the determinants of water resources availability,while twenty-eight countries were used to study the trend and improvement of water use efficiency.The study made a significant theoretical contribution by investigating the impact of urbanization,economic growth,agricultural growth,industrial development,and carbon dioxide(CO₂)emission on water resources.Besides,the spatial effect of urbanization,foreign direct investment,economic growth,educational level,and corruption on water use efficiency were also determined.Empirical methods which are robust and limit biases are employed for the study.Therefore,efficient results for the study samples are evident.To achieve the above-mentioned objectives,the study employed the pooled mean group–autoregressive lag(PMG-ADRL)to investigate the impact of urbanization,economic growth,agricultural growth,industrial development,and carbon emission on water resources availability.Afterward,the study employed the dynamic slack-based model of data envelopment analysis(DSBM-DEA)to evaluate the trend of water use efficiency for twenty-eight countries in SSA.The Malmquist Productivity Index was also used to explore the improvement of water use efficiency.Finally,the directional distance function of data envelopment analysis(DDF-DEA)was used to analyze the direction of water use efficiency.After the efficiency scores were established,the study used the Global Moran's index(I)and spatial regression models to estimate the long-run relationship among the selected variables.Finally,the direct and indirect spatial effects of the influencing factors on water use efficiency were assessed.The PMG-ADRL estimation result showed that AGR had a substantial negative effect on water resources availability in the UMI,LMI,and LI panels.Also,CO₂emissions had a significant positive liaison with water in the UMI,while on the side of the LMI and LI panels,an adverse influence was identified.Moreover,except for the UMI panel,GDPPC in the LMI panel was characterized by a significant negative affiliation.Contrarily,the GDPPC palpably influenced water in the LI panel.Markedly,apart from the LI panel where an immaterial effect of IND on the water was witnessed,a significant negative influence was found in the UMI and LMI panels of the sampled SSA economies.Finally,URB was evidenced to have a significant positive liaison with water in the UMI panel.Nonetheless,a substantial negative connection was found in the LMI and LI panels of SSA nations.Therefore,when strict policies and regulations concerning water resources management are not implemented,the water resources availability in a country,irrespective of the country's level of income,could be degraded.By means of the Dumitrescu-Hurlin granger causality,the study tested the causal relationship among the variables.The DSBM estimates showed that out of the sampled 28 countries,only Benin,Botswana,Burkina Faso,Gabon,Liberia,Mauritania,Namibia,South Africa,and Togo reached the efficiency frontier of 1.00.A total mean score of 0.64,0.61,0.59,and 0.3 were recorded for Southern Africa,West Africa,Central Africa,and East Africa,respectively,which were all less than 1.00.The Malmquist Productivity Index(MPI)overall recorded mean value with water stress was 0.969,and without water stress was 1.095.Apart from Angola,Burundi,Chad,Madagascar,Mauritania,Mozambique,Sierra Leone,and Togo,the rest of the sampled countries were technically efficient.However,none of the countries was technologically efficient.The findings from the spatial effects of the determinants of water use efficiency confirmed that urbanization and economic growth have a positive influence on water use efficiency while industrial growth and corruption had a significant adverse effect on water use efficiency.Conversely,foreign direct investment had an insignificant negative impact,whereas education level showed an insignificant positive influence water use efficiency.The main innovation of this study are as follows:the study investigated the effects of agricultural production,GDP,industrial development,carbon emission,and urbanization on the availability of water resources in SSA using second-generation econometric models.The study also extends the use of the DSBM and the MPI to explore the trend and improvement of water use efficiency in SSA.Furthermore,the spatial interactions of water use efficiency determinants in SSA are examined.To the best of the researcher's knowledge,little attention in previous studies has been given to these critical aspects of water resources management in SSA.The research primarily focuses on SSA because it has been one of the fastest urbanizing and yet water-scarce regions in the world.Based on the results,suggested policy recommendations include the following:First,various countries within sub-Saharan Africa should consider seeking professional guidance from countries such as China,Japan,the United States of America,and Israel,among others who are endowed with much knowledge and innovative technologies for processing,cultivating,consumption and storage that will foster water use efficiency and ensure sustainable water resources management.Second,the study recommends that multinational companies should be encouraged to improve their research and development to acquire more knowledge to reduce excessive consumption and pollution of water resources in the host countries.Third,there is an urgent need for policymakers in the water sector to raise awareness of the risk of water scarcity and encourage people's willingness to pay for water supply services.