Search

The International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences, Volume XLIV-4/W3-2020, 2020 5th International Conference on Smart City Applications, 7–8 October 2020, Virtual Safranbolu, Turkey (online) Water shortages are a chronic and severe problem in South Africa. Allocation of this limited water resources, environmental quality, and policies for sustainable water use are issues of increasing concern that require accurate and timely information to evolve strategies for dynamic natural resources management. Specifically, this paper is aimed to assist the planning, restoring and to rationally allocate the water resources in any river basin in resolving the current water stresses in many parts of South Africa, by using integrated knowledge from simulation and integrated river basin management approach. The developed system dynamic (SD) allocation system was used to investigates the extent to which the framework is ‘sustainable’ in the medium and long terms in evaluating existing and future water allocation among conflicting users at Mkomazi River Basin (MRB), KwaZulu-Natal Province, South Africa The invented SD framework confirms agricultural water use as the highest demand when compared with other users. The optimal sustainability performance index (0.25) of the system at 70% dependable flow shows an integrated scenario that combines rainfall variation with improved irrigation water use efficiency as a suitable framework plan. The study uses integrated knowledge from simulation and integrated river basin management approach as a feasible method to assist the planning, restoring and to rationally allocate the water resources in any river basin with similar attributes to the study area in resolving the current water stresses in many parts of the country. Water resources managers would find these tools beneficial in understanding the complex nature of water resources allocation and in determining priorities area which required prompt attention and intervention

The management of water resources for different purposes such as a domestic water supply and municipal, irrigation and hydropower generation requires optimization techniques for efficient reservoir operations. This study focused on the optimization of energy generation at Kainji hydropower station in Nigeria using operational and ecological integrity constraints. A linear optimization technique was used in optimizing the average total annual energy generation subject to operational and ecological integrity constraints. The model was solved using LINGO 17.0 software. The results revealed that the optimization approach would increase the total annual energy generation at the hydropower station by 1.84%. The outcome of this study can be adopted by the management of a hydropower station and other decision makers in Nigeria to improve the availability of electricity deployed to Nigeria’s national grid without compromising the ecological integrity of a reservoir.

Optimization models have been developed to maximize annual energy generation from the Doma dam, subject to the constraint of releases for irrigation, ecological purposes, the water supply, the maximum yield from the reservoir and reservoir storage. The model was solved with LINGO software for various mean annual inflow exceedence probabilities. Two scenarios of hydropower retrofitting were considered. Scenario 1, with the reservoir inflows at 50%, 75%, and 90% probabilities of exceedence, gives the total annual hydropower as 0.531 MW, 0.450 MW and 0.291 MW, respectively. The corresponding values for scenario 2 were 0.615 MW, 0.507 MW, and 0.346 MW respectively. The study also considered increasing the reservoir’s live storage to 32.63Mm3 by taking part of the flood storage so that the maximum draft increases to 7 Mm3. With this upper limit of storage and draft with reservoir inflows of 50%, 75% and 90% probabilities of exceedence, the hydropower generated increased to 0.609 MW, 0.540 MW, and 0.347 MW respectively for the scenario 1 arrangement, while those of scenario 2 increased to 0.699 MW, 0.579MW and 0.406 MW respectively. The results indicate that the Doma Dam is suitable for the production of hydroelectric power and that its generation potential is between 0.61 MW and 0.70 MW.

This study utilized Spatial Information Technology (SIT) such as Remote Sensing (RS), a Geographical Information System (GIS), the Global Positioning System (GPS) and a high-resolution Digital Elevation Model (DEM) for a morphometrical analysis of five sub-basins within the Lower Niger River Basin, Nigeria. Morpho-metrical parameters, such as the total relief, relative relief, relief ratio, ruggedness number, texture ratio, elongation ratio, circularity ratio, form factor ratio, drainage density, stream frequency, sinuosity factor and bifurcation ratio, have been computed and analyzed. The study revealed that the contribution of the morphometric parameters to flooding suggest catchment No. 1 has the least concentration time and the highest runoff depth. Catchment No. 4 has the highest circularity ratio (0.35) as the most hazardous site where floods could reach a great volume over a small area.

This study is focused on the application of Genetic Algorithm (GA) as an effective tool for modeling the operation of a multi-purpose reservoir with specific emphasis on Jebba Hydropower Dam, Nigeria. The specific objectives are to study the reservoir operation rule; model the reservoir parameters such as inflow, elevation, turbine release, generating head, energy generation, tailrace water level and plant coefficient. Available Data for 27-year period (1984–2011) was obtained from the Dam Station for statistical analysis. MATLab software for GA was used, and for comparison and check, another similar optimization software (LINGO) was utilized. The optimal solution obtained at operating performance of 50% reservoir inflow reliability has total annual energy generation of 42,105.63MWH. GA for the total annual energy generation at operation performance of 95, 90 and 75% reservoir inflow reliability are 15,964.48 MWH, 21,009.53 MWH and 20,798.58 MWH, respectively. The application of GA will lead to a more realistic and reliable optimal value for the improvement of hydroelectric power generation and flood management, which would guide decision makers in the hydropower sector.

This paper presents the evaluation of methods of determination of peak runoff for an ungauged catchment. The present study made use of Geographical Information System (GIS) for the morphometric analysis of four sub-catchments within Jere sub-basin in Gurara Basin, Nigeria. Various morphometric parameters were computed and analyzed as sub-basin characteristics are important factors in determining the runoff. Three methods of peak runoff estimation were used to determine peak runoff of the study area for four return periods. The results of the peak runoff estimation based on rational method for the four sub-catchments for 25-year, 50-year, 75-year and 100-year return periods varied between 224m3/s and 1036m3/s, while the results for the SCS method varied between 105.3m3/s and 162.05m3/s and the results from the Cypress Creek method varied between 22.8m3/s and 86.55m3/s. The results obtained from the three methods showed that there are significant differences in the peak runoff results and also there are significant differences in the peak runoff results for the different return periods.

In this study, a calibrated hydrologic model, Soil and Water Assessment Tool (SWAT) interfaced with Geographical Information System (GIS) tool was used to study the effect of different sediment management methods in a watershed (12,992 km2) upstream of Jebba Lake, Nigeria. Sediment management strategies considered are (i) reforestation of the watershed, (ii) application of vegetative filter strip (VFS) and (iii) construction of stone bunds. Cost analysis of implementing the selected erosion control measures within the watershed was also carried out to compare the cost effectiveness of each of the management strategies. The results showed that application of VFS, reforestation, and stone bunds to critical zones of the watershed reduced the sediment yield up to 65.6%, 63.4% and 12% respectively while the financial analysis of implementing reforestation, VFS and stone bunds revealed 84.9%, 73.3% and 70.5% reduction respectively in the costs to be incurred if sediments are allowed to accumulate in the dam. From this analysis, it can be concluded that the sediment management scenarios considered in this study are cost effective and sustainable when compared with the costs incurred in tackling the effect due to reservoir sedimentation. Overall, the study showed that hydrological models such as SWAT can be used to study strategies for water resource management. In addition, it can provide policy makers the decision support tools to evaluate the cost and benefits of adopting Best Management Practices (BMPs) particularly for sediment control in erosion prone watersheds. Keywords: Cost analysis, Jebba Reservoir, Sediment management, SWAT, Watershed