Improving water use efficiency under worsening scarcity: Evidence from the Middle Olifants sub-basin in South Africa

With the political changes in South Africa in the early 1990s, the South African government introduced a reform process in the entire water sector with the goal of a more enhanced and equitable water management system. This paper analyzes existing water allocation situations and applies a nonlinear optimization model to investigate the optimal intra- and inter-regional allocations in the Middle Olifants sub-basin of South Africa. Results show higher benefit from inter-regional water allocation. Reducing water supply levels to conform to the sustainable water supply policy, it can be shown that although water supply is reduced by approximately 50%, total benefits from water are only reduced by 5% and 11% for inter- and intra-regional allocation regimes respectively. These results indicate that alternative water allocation mechanisms can serve as instruments to offset for the effects of water scarcity.Water allocation, IWRM, Olifants basin, South Africa, Africa, Resource /Energy Economics and Policy,

Development and validation of risk profiles of West African rural communities facing multiple natural hazards

West Africa has been described as a hotspot of climate change. The reliance on rain-fed agriculture by over 65% of the population means that vulnerability to climatic hazards such as droughts, rainstorms and floods will continue. Yet, the vulnerability and risk levels faced by different rural social-ecological systems (SES) affected by multiple hazards are poorly understood. To fill this gap, this study quantifies risk and vulnerability of rural communities to drought and floods. Risk is assessed using an indicator-based approach. A stepwise methodology is followed that combines participatory approaches with statistical, remote sensing and Geographic Information System techniques to develop community level vulnerability indices in three watersheds (Dano, Burkina Faso; Dassari, Benin; Vea, Ghana). The results show varying levels of risk profiles across the three watersheds. Statistically significant high levels of mean risk in the Dano area of Burkina Faso are found whilst communities in the Dassari area of Benin show low mean risk. The high risk in the Dano area results from, among other factors, underlying high exposure to droughts and rainstorms, longer dry season duration, low caloric intake per capita, and poor local institutions. The study introduces the concept of community impact score (CIS) to validate the indicator-based risk and vulnerability modelling. The CIS measures the cumulative impact of the occurrence of multiple hazards over five years. 65.3% of the variance in observed impact of hazards/CIS was explained by the risk models and communities with high simulated disaster risk generally follow areas with high observed disaster impacts. Results from this study will help disaster managers to better understand disaster risk and develop appropriate, inclusive and well integrated mitigation and adaptation plans at the local level. It fulfills the increasing need to balance global/regional assessments with community level assessments where major decisions against risk are actually taken and implemented

Design and baseline characteristics of the finerenone in reducing cardiovascular mortality and morbidity in diabetic kidney disease trial

Background: Among people with diabetes, those with kidney disease have exceptionally high rates of cardiovascular (CV) morbidity and mortality and progression of their underlying kidney disease. Finerenone is a novel, nonsteroidal, selective mineralocorticoid receptor antagonist that has shown to reduce albuminuria in type 2 diabetes (T2D) patients with chronic kidney disease (CKD) while revealing only a low risk of hyperkalemia. However, the effect of finerenone on CV and renal outcomes has not yet been investigated in long-term trials. Patients and Methods: The Finerenone in Reducing CV Mortality and Morbidity in Diabetic Kidney Disease (FIGARO-DKD) trial aims to assess the efficacy and safety of finerenone compared to placebo at reducing clinically important CV and renal outcomes in T2D patients with CKD. FIGARO-DKD is a randomized, double-blind, placebo-controlled, parallel-group, event-driven trial running in 47 countries with an expected duration of approximately 6 years. FIGARO-DKD randomized 7,437 patients with an estimated glomerular filtration rate >= 25 mL/min/1.73 m(2) and albuminuria (urinary albumin-to-creatinine ratio >= 30 to <= 5,000 mg/g). The study has at least 90% power to detect a 20% reduction in the risk of the primary outcome (overall two-sided significance level alpha = 0.05), the composite of time to first occurrence of CV death, nonfatal myocardial infarction, nonfatal stroke, or hospitalization for heart failure. Conclusions: FIGARO-DKD will determine whether an optimally treated cohort of T2D patients with CKD at high risk of CV and renal events will experience cardiorenal benefits with the addition of finerenone to their treatment regimen. Trial Registration: EudraCT number: 2015-000950-39; ClinicalTrials.gov identifier: NCT02545049

A Service of zbw Leibniz-Informationszentrum Wirtschaft Leibniz Information Centre for Economics Improving water use efficiency under worsening scarcity: Evidence from the middle Olifants sub-basin in South Africa Improving water use efficiency under wors

Standard-Nutzungsbedingungen: Die Dokumente auf EconStor dürfen zu eigenen wissenschaftlichen Zwecken und zum Privatgebrauch gespeichert und kopiert werden. Sie dürfen die Dokumente nicht für öffentliche oder kommerzielle Zwecke vervielfältigen, öffentlich ausstellen, öffentlich zugänglich machen, vertreiben oder anderweitig nutzen. Sofern die Verfasser die Dokumente unter Open-Content-Lizenzen (insbesondere CC-Lizenzen) zur Verfügung gestellt haben sollten, gelten abweichend von diesen Nutzungsbedingungen die in der dort genannten Lizenz gewährten Nutzungsrechte. Terms of use: Documents in Acknowledgements This work is part of the BMBF-funded project on &quot;Integrated Water Resources Management Pilot Project in the Middle Olifants Sub-basin of South Africa&quot;. We would like to thank Dr. Anik Bhaduri from ZEF and Dr. Charles Rodgers for their review and insightful comments on the earlier versions of the manuscript. Abstract With the political changes in South Africa in the early 1990s, the South African government introduced a reform process in the entire water sector with the goal of a more enhanced and equitable water management system. This paper analyzes existing water allocation situations and applies a nonlinear optimization model to investigate the optimal intra-and inter-regional allocations in the Middle Olifants sub-basin of South Africa. Results show higher benefit from inter-regional water allocation. Reducing water supply levels to conform to the sustainable water supply policy, it can be shown that although water supply is reduced by approximately 50%, total benefits from water are only reduced by 5% and 11% for inter-and intra-regional allocation regimes respectively. These results indicate that alternative water allocation mechanisms can serve as instruments to offset for the effects of water scarcity

Preferences for domestic water services in the Middle Olifants sub-basin of South Africa

Using household survey data, this study investigates preferences for domestic water services in the Middle Olifants sub-basin of South Africa. Water is a relative scarce resource in South Africa that is distributed unevenly both geographically and seasonally as well as socio-politically. For a water management addressing the policy objectives of efficiency in use, equity in access and benefits and long-term sustainability, economic valuation of the different water uses is required. In order to detect households' preferences, a choice experiment was conducted. Results suggested the presence of preference heterogeneity and therefore, a latent class model was applied, dividing households into homogeneous groups according to their preferences. Four distinct groups of households could be found which differ significantly in terms of their socio-economic characteristics, their attitudes toward pricing of water and their satisfaction with current water service levels. Willingness to pay (WTP) estimates of different water service characteristics in all groups indicate that households are willing to pay higher prices for a better and more reliable water services provision. But the amount households are willing to pay differs among the groups. This information is helpful for policy-makers to enable the design of water services in the Middle Olifants according to preferences of local households. Besides, WTP estimation can provide a basis for setting water tariffs

Improving water use efficiency under worsening scarcity: Evidence from the Middle Olifants sub-basin in South Africa

With the political changes in South Africa in the early 1990s, the South African government introduced a reform process in the entire water sector with the goal of a more enhanced and equitable water management system. This paper analyzes existing water allocation situations and applies a nonlinear optimization model to investigate the optimal intra- and inter-regional allocations in the Middle Olifants sub-basin of South Africa. Results show higher benefit from inter-regional water allocation. Reducing water supply levels to conform to the sustainable water supply policy, it can be shown that although water supply is reduced by approximately 50%, total benefits from water are only reduced by 5% and 11% for inter- and intra-regional allocation regimes respectively. These results indicate that alternative water allocation mechanisms can serve as instruments to offset for the effects of water scarcity

Economic analysis of water supply cost structure in the Middle Olifants sub-basin of South Africa

Using data gathered from the National Treasury of South Africa, we examine the structure of water supply costs and tariffs of Water Service Authorities (WSAs) in the Middle Olifants sub-basin of South Africa. Using the translog cost function method, the marginal cost of water supply and economies of scale are estimated. Comparison of tariffs and marginal costs show that the estimated marginal cost is higher than the actual tariff paid by consumers. This implies that WSAs in the Middle Olifants are not charging enough to recover the costs of the water services. Thus, among other things, pricing of water at its marginal cost would partly assist in solving the cost recovery problem. Raised tariffs would in turn contribute to improved efficiency of water use. As evidenced by estimation results of returns to scale (greater than one), merger of WSAs would be economically advantageous. Hence, reversing the process of transferring water services’ authority to ‘local’ municipality level and thus up-scaling WSAs into the ‘district’ municipality level is an important policy option for improving water services efficiency in the Middle Olifants sub-basin of South Africa