Your search found 12 records
1 Choudhry, M. R.; Bhutta, M. N. 2000. Problems impeding the sustainability of drainage systems in Pakistan. Proceedings, Volume II and recommendations, National Seminar on Drainage in Pakistan, August 16-18, 2000, sponsored by National Drainage Program (NDP) and WAPDA, Pakistan, and organized by Institute of Irrigation & Drainage Engineering, Mehran University of Engineering & Technology (MUET), Jamshoro, Sindh, Pakistan, in collaboration with IWASRI, Lahore, Pakistan and IIMI, Pakistan. pp.11-20.
Surface drainage ; Pipes ; Sustainability ; Water table ; Waterlogging ; Salinity ; Irrigated farming ; Soil reclamation ; Operations ; Maintenance ; Performance assessment / Pakistan
(Location: IWMI-HQ Call no: IIMI 631.62 G730 IIM Record No: H027148)
2 Higginbottom, T. P.; Adhikari, R.; Dimova, R.; Redicker, S.; Foster, T. 2021. Performance of large-scale irrigation projects in Sub-Saharan Africa. Nature Sustainability, 4:501-508. [doi: https://doi.org/10.1038/s41893-020-00670-7]
Irrigation programs ; Irrigation schemes ; Large scale systems ; Performance assessment ; Infrastructure ; Water balance ; Policies ; Political aspects ; Food security / Africa South of Sahara
(Location: IWMI HQ Call no: e-copy only Record No: H050695)
(1.83 MB)
After a 30-year hiatus, large-scale irrigation projects have returned to the development agenda in sub-Saharan Africa (SSA). However, the magnitude and drivers of past schemes’ performance remains poorly understood. We quantify the performance, measured as the proportion of proposed irrigated area delivered, of 79 irrigation schemes from across SSA by comparing planning documents with estimates of current scheme size from satellite-derived land-cover maps. We find overwhelming evidence that investments have failed to deliver promised benefits, with schemes supporting a median 16% of proposed area, only 20 (25%) delivering >80% and 16 (20%) completely inactive. Performance has not improved over six decades and we find limited relationships with commonly stated causes of failure such as scheme size and climate. We attribute these findings to political and management frameworks underpinning irrigation development in SSA. First, an emphasis on national food security promotes low-value crops, reducing economic viability. Second, proposals are unrealistically large, driven by optimism bias and political incentives. Finally, centralized bureaucracies lack the technical expertise, local knowledge and financial resources to ensure long-term maintenance. Our findings highlight the need for greater learning from past investments’ outcomes if improvements in agricultural productivity and water security across SSA are to be realized.
3 Belay, A. M.; Assefa, T. T.; Belay, S. A.; Yimam, A. Y. 2023. Evaluating the performance of small-scale irrigation schemes in subhumid Ethiopian highlands. Irrigation and Drainage, 72(1):224-239. [doi: https://doi.org/10.1002/ird.2753]
Small-scale irrigation ; Irrigation schemes ; Irrigation water ; Performance assessment ; Highlands ; Subhumid zones ; Infiltration rate ; Crop water use ; Water requirements ; Water supply ; Indicators ; Water management ; Infrastructure / Ethiopia
(Location: IWMI HQ Call no: e-copy only Record No: H051702)
(0.72 MB)
This study was conducted to evaluate the performance of two small-scale irrigation (SSI) schemes in the subhumid Ethiopian highlands. Water application at the farm level and flow velocity along the main canal were monitored using a Parshall flume and current meter, respectively. The infiltration was measured at the head, middle and tail of the scheme within the command area using a double-ring infiltrometer. Soil samples were collected using an auger up to 60 cm in depth. Climatic and agronomic data were supplied to the crop water assessment tool (CROPWAT) to determine crop water requirements. The results showed that the average conveyance efficiency for the lined main canal was 90% and 92% for the Mugie and Fesas SSI schemes, respectively. The conveyance efficiency for the unlined main canal was in the order of 86% and 87% for the Mugie and Fesas SSI schemes, respectively. On the other hand, the average application efficiency and overall efficiency were found to be 56% and 51%, respectively, with a storage efficiency of 50% for the Mugie irrigation scheme. Similarly, the overall, application and storage efficiencies were 50%, 54% and 56%, respectively, for the Fesas irrigation scheme. Failure of operating gates, canal siltation and leakage through the main canals were the main causes of poor performance.
4 Okem, Andrew Emmanuel. 2023. Assessing the performance of cooperatives in post-apartheid South Africa: evidence from the literature. Development Southern Africa, 40(6):1200-1213. [doi: https://doi.org/10.1080/0376835X.2023.2212705]
Cooperatives ; Performance assessment ; Apartheid ; Economic aspects ; Financing ; Indicators ; Government ; State intervention / South Africa
(Location: IWMI HQ Call no: e-copy only Record No: H052031)
(1.83 MB)
While there is growing interest in the literature and policy circles regarding the performance of cooperatives in South Africa, no study has yet synthesised the body of knowledge on how to assess cooperative performance in the country. This paper aims to fill this gap by examining the literature on the performance of cooperatives in post-apartheid South Africa, based on a scoping review of 20 studies published between 1994 and 2021. Most of the reviewed studies adopted a qualitative approach, lacked a clear definition of cooperative performance and standardised metrics/criteria for assessing cooperative performance. The studies often relied on view of study participants to determine the performance of cooperatives. Moreover, the reviewed studies often framed the performance of cooperatives from an economic viewpoint. Clear definition of cooperatives, the development of robust indicators for assessing their performance and greater emphasis on quantitative studies on the performance of cooperatives in South Africa beyond economic and financial indicators is needed.
5 Incoom, A. B. M.; Adjei, K. A.; Odai, S. N.; Akpoti, Komlavi; Siabi, E. K.; Awotwi, A. 2023. Assessing climate model accuracy and future climate change in Ghana's Savannah regions. Journal of Water and Climate Change, 14(7):2362-2383. [doi: https://doi.org/10.2166/wcc.2023.070]
Climate models ; Performance assessment ; Climate prediction ; Climate change adaptation ; Strategies ; Precipitation ; Rainfall patterns ; Temperature ; Weather forecasting ; Savannahs / West Africa / Ghana / Savannah Zone / Bole / Kete-Krachi / Kintampo / Tamale / Wa / Wenchi / Zuarungu / Navrongo / Yendi
(Location: IWMI HQ Call no: e-copy only Record No: H052102)
https://iwaponline.com/jwcc/article-pdf/14/7/2362/1267240/jwc0142362.pdf
https://vlibrary.iwmi.org/pdf/H052102.pdf
https://vlibrary.iwmi.org/pdf/H052102.pdf
(1.52 MB) (1.52 MB)
This study aimed to compare the performance of six regional climate models (RCMs) in simulating observed and projecting future climate in the Savannah zone of Ghana, in order to find suitable methods to improve the accuracy of climate models in the region. The study found that the accuracy of both individual RCMs and their ensemble mean improved with bias correction, but the performance of individual RCMs was dependent on location. The projected change in annual precipitation indicated a general decline in rainfall with variations based on the RCM and location. Projections under representative concentration pathway (RCP) 8.5 were larger than those under RCP 4.5. The changes in mean temperature recorded were 1 °C for the 2020s for both RCPs, 1–4 °C for the 2050s under both RCPs, and 1– 4 °C under RCP 4.5, and from 2 to 8 °C for the 2080s. These findings will aid farmers and governments in the West African subregion in making informed decisions and planning cost-effective climate adaptation strategies to reduce the impact of climate change on the ecosystem. The study highlights the importance of accurate climate projections to reduce vulnerability to climate change and the need to improve climate models in projecting climate in the West African subregion.
6 Berhanu, D.; Alamirew, T.; Taye, Meron Teferi; Tibebe, D.; Gebrehiwot, S.; Zeleke, G. 2023. Evaluation of CMIP6 models in reproducing observed rainfall over Ethiopia. Journal of Water and Climate Change, 14(8):2583-2605. [doi: https://doi.org/10.2166/wcc.2023.502]
Climate models ; Performance assessment ; Evaluation ; Rainfall patterns ; Spatial distribution ; Trends ; Precipitation ; Seasonal variation ; Datasets ; Climate change / Ethiopia
(Location: IWMI HQ Call no: e-copy only Record No: H052162)
https://iwaponline.com/jwcc/article-pdf/14/8/2583/1277280/jwc0142583.pdf
https://vlibrary.iwmi.org/pdf/H052162.pdf
https://vlibrary.iwmi.org/pdf/H052162.pdf
(1.79 MB) (1.79 MB)
Ethiopia is highly susceptible to the effects of climate change and variability. This study evaluated the performances of 37 CMIP6 models against a gridded rainfall product of Ethiopia known as Enhancing National Climate Services (ENACTS) in simulating the observed rainfall from 1981 to 2014. Taylor Skill Score was used for ranking the performance of individual models for mean monthly, June–September, and February–May seasonal rainfall. Comprehensive rating metrics (RM) were used to derive the overall ranks of the models. Results show that the performances of the models were not consistent in reproducing rainfall distributions at different statistical metrics and timeframes. More than 20 models simulated the largest dry bias on high topographic and rainfall-receiving areas of the country during the June–September season. The RM-based overall ranks of CMIP6 models showed that GFDL-CM4 is the best-performing model followed by GFDL-ESM4, NorESM2-MM, and CESM2 in simulating rainfall over Ethiopia. The ensemble of these four Global Climate Models showed the best performance in representing the spatiotemporal patterns of the observed rainfall relative to the ensembles of all models. Generally, this study highlighted the existence of dry bias in climate model projections for Ethiopia, which requires bias adjustment of the models, for impact assessment.
7 Mekonnen, Kirubel; Velpuri, Naga Manohar; Leh, Mansoor; Akpoti, Komlavi; Owusu, Afua; Tinonetsana, Primrose; Hamouda, T.; Ghansah, B.; Paranamana, Thilina Prabhath; Munzimi, Y. 2023. Accuracy of satellite and reanalysis rainfall estimates over Africa: a multi-scale assessment of eight products for continental applications. Journal of Hydrology: Regional Studies, 49:101514. [doi: https://doi.org/10.1016/j.ejrh.2023.101514]
Rainfall ; Estimation ; Satellites ; Datasets ; Models ; Performance assessment ; Evaluation ; Climatology ; River basins ; Climatic zones ; Rain gauges ; Observation / Africa
(Location: IWMI HQ Call no: e-copy only Record No: H052164)
https://www.sciencedirect.com/science/article/pii/S221458182300201X/pdfft?md5=eeafc6b121eec039f2a2cd37cb0c7e67&pid=1-s2.0-S221458182300201X-main.pdf
https://vlibrary.iwmi.org/pdf/H052164.pdf
https://vlibrary.iwmi.org/pdf/H052164.pdf
(14.00 MB) (14.0 MB)
Study Region: Continental Africa
Study Focus: This study evaluates the accuracy of eight gauge-corrected rainfall products across Africa through direct comparisons with in situ observations for the period 2001–2020. The effect of validation datasets on the performance of the rainfall products was also quantified in ten African countries. Four categorical and five continuous metrics were estimated at multiple spatial and temporal scales as part of the evaluation.
New hydrological insights for the Region: Results indicate that the performance of the rainfall products varied in space and time. Evaluation at temporal scales revealed that, on average, most rainfall products showed poor results (KGE < 0.35) at the daily timescale. In contrast, RFE v2.0, ARC v2.0, and MSWEP v2.8 were reliable (KGE > 0.75) at the monthly and annual timescales. Among the rainfall products, the performance of TAMSATv3.1, PERSIANN-CDR, and ERA 5 was relatively poor in capturing in situ observations. Evaluation at various spatial scales revealed mixed results. The ARC v2.0 and CHIRPS v2.0 rainfall products were reliable in detecting no rains (< 1 mm/day) for all 19 spatial scales, indicating a high level of confidence for drought studies. IMERG-F v6B and RFE v2.0 were reliable in detecting heavy and high-intensity rainfall events for all spatial scales. Using the KGE performance metrics at the regional level, MSWEP v2.8 in the Northern Africa region, RFE v2.0 in the Western and Southern Africa regions, ARC v2.0 in Central Africa, and CHIRPS v2.0 in the Eastern Africa region showed better performances at monthly timescale. Moreover, the performance of the gauge-corrected rainfall datasets was reduced when compared with independent validation data (gauge data not used by rainfall products) than dependent validation data. This study provides several new insights into choosing a rainfall product for continental to regional applications and identifies the need for bias correction.
Study Focus: This study evaluates the accuracy of eight gauge-corrected rainfall products across Africa through direct comparisons with in situ observations for the period 2001–2020. The effect of validation datasets on the performance of the rainfall products was also quantified in ten African countries. Four categorical and five continuous metrics were estimated at multiple spatial and temporal scales as part of the evaluation.
New hydrological insights for the Region: Results indicate that the performance of the rainfall products varied in space and time. Evaluation at temporal scales revealed that, on average, most rainfall products showed poor results (KGE < 0.35) at the daily timescale. In contrast, RFE v2.0, ARC v2.0, and MSWEP v2.8 were reliable (KGE > 0.75) at the monthly and annual timescales. Among the rainfall products, the performance of TAMSATv3.1, PERSIANN-CDR, and ERA 5 was relatively poor in capturing in situ observations. Evaluation at various spatial scales revealed mixed results. The ARC v2.0 and CHIRPS v2.0 rainfall products were reliable in detecting no rains (< 1 mm/day) for all 19 spatial scales, indicating a high level of confidence for drought studies. IMERG-F v6B and RFE v2.0 were reliable in detecting heavy and high-intensity rainfall events for all spatial scales. Using the KGE performance metrics at the regional level, MSWEP v2.8 in the Northern Africa region, RFE v2.0 in the Western and Southern Africa regions, ARC v2.0 in Central Africa, and CHIRPS v2.0 in the Eastern Africa region showed better performances at monthly timescale. Moreover, the performance of the gauge-corrected rainfall datasets was reduced when compared with independent validation data (gauge data not used by rainfall products) than dependent validation data. This study provides several new insights into choosing a rainfall product for continental to regional applications and identifies the need for bias correction.
8 Chandra, A.; Heeren, D. M.; Odhiambo, L.; Brozovic, N. 2023. Water-energy-food linkages in community smallholder irrigation schemes: center pivot irrigation in Rwanda. Agricultural Water Management, 289:108506. (Online first) [doi: https://doi.org/10.1016/j.agwat.2023.108506]
Irrigation schemes ; Smallholders ; Water requirements ; Energy generation ; Food security ; Nexus approaches ; Performance assessment ; Decision making ; Water policies ; Water management ; Crop yield ; Irrigation water ; Water productivity ; Water balance ; Econometric models ; Agricultural production ; Farmer-led irrigation ; Water use / Africa South of Sahara / Rwanda
(Location: IWMI HQ Call no: e-copy only Record No: H052350)
https://www.sciencedirect.com/science/article/pii/S0378377423003712/pdfft?md5=4b3ac120fb0d46832d22e2ba14130869&pid=1-s2.0-S0378377423003712-main.pdf
https://vlibrary.iwmi.org/pdf/H052350.pdf
https://vlibrary.iwmi.org/pdf/H052350.pdf
(3.31 MB) (3.31 MB)
Water, energy, and food are linked in intricate ways in irrigated agriculture and understanding the interplay of these components is crucial for sustainable and profitable crop production, particularly in smallholder setting such as in sub-Saharan Africa. This study evaluates water-energy-food linkages, engineering and economic performance, irrigation decision making, and challenges faced around water management in a community-based mechanized irrigation scheme in Rwanda. The research is the first to analyze such as scheme, which uses technology typically used by large farmers in a smallholder setting. The study investigates the variation in water requirements and the relationship and impacts of this variability on crop yield for the crops grown in the scheme: maize, French beans, and dry beans. Observed irrigation decision-making analyses demonstrate a lack of irrigation planning during growth stages and significant field-to-field variation in irrigation; this is linked to yield reduction in major crops. Results suggest that farmers irrigated only 31% of modeled irrigation water in dry beans and 27% of modeled irrigation water in maize. An econometric model assessment is used to understand the relationship between yield and energy inputs. A related policy analysis considers the impacts of changes in crop and water management on field-level profits and system-level financial sustainability. This study has implications for understanding irrigation policies in the context of the water-energy-food nexus and decision-making in Sub-Saharan Africa.
9 Aniley, E.; Gashaw, T.; Abraham, T.; Demessie, S. F.; Bayabil, H. K.; Worqlul, A. W.; van Oel, P. R.; Dile, Y. T.; Chukalla, A. D.; Haileslassie, Amare; Wubaye, G. B. 2023. Evaluating the performances of gridded satellite/reanalysis products in representing the rainfall climatology of Ethiopia. Geocarto International, 38(1):2278329. [doi: https://doi.org/10.1080/10106049.2023.2278329]
Rainfall ; Datasets ; Weather data ; Performance assessment ; Climatology ; Satellite observation ; Agroecological zones ; Precipitation / Ethiopia
(Location: IWMI HQ Call no: e-copy only Record No: H052402)
https://www.tandfonline.com/doi/epdf/10.1080/10106049.2023.2278329?needAccess=true
https://vlibrary.iwmi.org/pdf/H052402.pdf
https://vlibrary.iwmi.org/pdf/H052402.pdf
(3.33 MB) (3.33 MB)
This study evaluated performances of the Climate Hazard Group Infrared Precipitation with stations version 2.0 (CHIRPS v2.0) and Multi-Source Weighted-Ensemble Precipitation version 2.8 (MSWEP v2.8) products against observed data. Rainfall climatology was simulated for different agro-ecological zones (AEZs) of Ethiopia during 1991–2020 at different temporal scales. Performance evaluations were made using continuous and statistical performance measures as well as Probability Density Function (PDF). CHIRPS v2.0 for estimating monthly, seasonal, and annual rainfall totals, and MSWEP v2.8 for daily rainfall have shown better performance over all AEZs. The two products display comparable performance for detecting daily rainfall occurrences over alpine AEZ, but MSWEP v2.8 is superior in the rest four AEZs. CHIRPS v2.0 outperforms MSWEP v2.8 for detecting most of the daily rainfall intensity classes over all AEZs. The findings will play a noteworthy role to improve the quality of hydro-climate studies in Ethiopia.
10 Dai, X.; Garrick, D.; Svensson, J.; Li, J.; Yue, Q. 2023. Performance evaluation of China's agricultural water rights markets (2002–2020) Water Policy, 25(12):1187-1205. [doi: https://doi.org/10.2166/wp.2023.232]
Water rights ; Water markets ; Agricultural water use ; Performance assessment ; Sustainability ; Economic development ; Water supply ; Water conservation ; Villages ; Irrigation water ; Surface water ; Evaluation ; Indicators / China / Zhangye / Heihe River Basin
(Location: IWMI HQ Call no: e-copy only Record No: H052457)
https://iwaponline.com/wp/article-pdf/25/12/1187/1344911/025121187.pdf
https://vlibrary.iwmi.org/pdf/H052457.pdf
https://vlibrary.iwmi.org/pdf/H052457.pdf
(0.72 MB) (740 KB)
The water rights market has been promoted in China since 2000. The lack of data and suitable evaluation methods impeded efforts to evaluate the market performance systematically. This research examines the characteristics, performance, and variation of China's agricultural water rights market (AWRM) on the basis of data from the field investigation, China Water Exchange, academic literature, and policy documents. We construct a comprehensive evaluation index system from the aspects of efficiency, fairness, and sustainability and quantitatively evaluate the performance of seven typical agricultural water markets in China. From 2002 to 2020, there were 1,752 cases of agricultural water transactions in China, with a total trading volume of 10.09 million m3. The market scale is increasing and the development of AWRM can be divided into three stages. Most agricultural water rights transactions happened in the west and the north. The average performance of typical AWRMs was poor. Typical water markets had the highest score for fairness and the lowest score for sustainability. Water markets in the humid areas performed the best, whereas the markets in the higher transaction level performed better. Water markets in areas with higher economic development had better performance.
11 Ahmad, M. T.; Haie, N.; Goncalves, J. M.; Pinho, J.; Yen, H.; Yakubu, M. L.; Mohammed, M. U.; Suleimana, A. 2024. Performance assessment and indicators for agricultural water management-a review. Water and Environment Journal, 20p. (Online first) [doi: https://doi.org/10.1111/wej.12913]
Agricultural water management ; Indicators ; Performance assessment ; Irrigation management ; Irrigation systems ; Water productivity ; Water supply ; Evapotranspiration ; Sustainability ; Case studies
(Location: IWMI HQ Call no: e-copy only Record No: H052743)
(2.59 MB)
The complexity of irrigation systems and the need to adapt them to uncertainties requires developing approaches to synthesize their performances. This paper reviews performance assessment and indicators for agricultural water systems. It is aimed at finding various methods and indices used for irrigation performance assessment and standard classes for their characterization. The global application of the metrics was also documented. Adopting a systematic review approach, peer-reviewed journal articles published in the English language in the last two decades (1 March 2001 to 31 December 2020) were surveyed. Case studies were presented demonstrating the application of the indicators. The study revealed a lack of standardization and the use of a wide range of indicators among others, and recommended representing certain indicators as single. However, this review considered one indicator as the best. Suggestions for further studies were made.
12 Malota, M.; Taguta, C.; Dirwai, Tinashe Lindel; Mabhaudhi, Tafadzwanashe; Senzanje, A. 2024. Assessing the performance of WaSim and DRAINMOD models for subsurface drainage design and analysis in a data-scarce environment. Journal of the ASABE, 67(4):917-930. [doi: https://doi.org/10.13031/ja.15515]
Subsurface drainage ; Simulation models ; Performance assessment ; Water management ; Water table ; Percolation ; Drainage systems ; Soil hydraulic properties ; Hydraulic conductivity ; Soil water retention ; Soil chemicophysical properties ; Discharges ; Decision-support systems / South Africa / KwaZulu-Natal / Pongola
(Location: IWMI HQ Call no: e-copy only Record No: H053002)
https://elibrary.asabe.org/azdez.asp?search=0&JID=3&AID=54941&CID=ja2024&v=67&i=4&T=2
https://vlibrary.iwmi.org/pdf/H053002.pdf
https://vlibrary.iwmi.org/pdf/H053002.pdf
(1.86 MB) (1.86 MB)
Simulation models are useful decision-support tools for designing and analyzing subsurface drainage systems in irrigated lands. However, the challenge is determining the soil hydraulic data inputs required by models to achieve reliable and accurate simulation of water table depths (WTDs) and drainage discharges (DDs) at various drain depths and spacing combinations. This is particularly important for data-scarce areas, such as middle- and low-income countries (MLICs), that lack facilities to determine in-situ soil hydraulic properties. We evaluated the performance of WaSim and DRAINMOD models to simulate WTDs and DDs at a field scale in KwaZulu-Natal, South Africa. Saturated hydraulic conductivity (Ksat) and soil water retention ( (h)) values were determined using the in-situ pumping test and a pressure plate apparatus. Pedotransfer functions (PTFs) in the Rosetta computer program also estimated these soil parameters. The DRAINMOD and WaSim models were calibrated using the in-situ measured Ksat and laboratory-measured (h) data, while the validation exercise used the PTFs-estimated Ksat and (h) data as soil hydraulic inputs. The models’ performance in simulating WTDs and DDs was assessed using Nash-Sutcliffe Model Efficiency (NSE), Modified Index of Agreement (d), Coefficient of Determination (R2 ), and Mean Absolute Error (MAE). During validation, DRAINMOD simulated WTDs with NSE, d, R2 , and MAE of 0.86, 0.81, 0.89, and 5.3 cm, respectively, whereas, for DDs, the model registered NSE, d, R2 , and MPE of 0.81, 0.79, 0.83, and 0.17 mm.day-1, respectively. During the validation period, the WaSim model simulated WTDs with NSE, d, R2 , and MAE of 0.76, 0.74, 0.78, and 9.0 cm, respectively. For the same validation period, the WaSim model simulated DDs with NSE, d, R2 , and MAE of 0.74, 0.73, 0.77, and 0.2 mm.day-1, respectively. The results suggest that both models, with either in-situ measured and laboratory-measured soil data or PTFs-estimated soil data, can be used to design and analyze drainage systems in data-scarce environments with a reasonably high confidence level. Designers of subsurface drainage systems in Pongola, South Africa, can use any of the two drainage models as decision support tools. We recommend using DRAINMOD and WaSim models with PTFs-estimated hydraulic soil data based on soil textural information, soil particle size data, bulk density, and (h) data at field capacity and permanent wilting point.
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