Mahsa Tashakori; Mehdi Hayatzadeh; Ali Fathzadeh; Javad Chezgi; Akram Bemani Kharanagh
Abstract
Introduction The most important problem in the development and construction of underground dams is the complexity of determining suitable areas for dam construction. This problem arises from the fact that many criteria and factors including social, economic, geological and hydrological criteria are involved ...
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Introduction The most important problem in the development and construction of underground dams is the complexity of determining suitable areas for dam construction. This problem arises from the fact that many criteria and factors including social, economic, geological and hydrological criteria are involved in its proper location. Therefore, it is important to use methods that can determine suitable places for the construction of underground dams with high accuracy and with the least amount of time and cost. The construction of an underground dam is recommended as one of the solutions for water supply in arid areas where there is no access to usual sources, such as wells and permanent rivers, or they have few water resources. For this purpose, in the present study, the location of the prone areas for the construction of such dams has been investigated. The studied area is the Rodan Watershed in Hormozgan Province, which has a good potential for the construction of an underground dam due to its dry climate and special geological conditions.Materials and methodsIn this study, the number of eight initial locations were identified as potential points for construction underground dam by combining digital elevation model, topographic features, geological and hydrological features in GIS. In the following, after forming the decision matrix using Vicor model, ranking, determining the index and selecting the smallest index as the best option were done. Finally, the options were sorted based on the values of desirability index, dissatisfaction index and Vicor index. Then, the best option that has the smallest Vicor index was selected.Results and discussionAccording to the obtained results, the value of Vikor index (Q) was 0.0158 and 0.097 for sites 5 and 2, respectively, and that way, based on Vikor index, the first rank belonged to the site 5 and the second rank belonged to the site 2. Therefore, out of the initial eight locations, only two places were suitable spots and other suitable sites were rejected due to the distance from the centers of population concentration and agriculture. Rank one, located in the east of Ziarat Ali, is one of the best places to build an underground dam due to the hydrological and topographical conditions, including the fact that the slope in this site is less than five percent. The second priority, located in the north of Brentin district, was considered as a suitable option for the construction of an underground dam due to its location in the vicinity of a sparsely populated village where drinking water is supplied through a well. Among the criteria used in the present research, the criteria of water need, distance from the village, pH and EC parameters, and water quantity were the most important in the sites that have been assigned the first and second priority.Conclusion Examining the results of the reservoir surface factor in this research showed that the larger the reservoir surface, the higher the priority in locating this structure. In underground dams, unlike surface dams where the large reservoir surface is considered a disadvantage due to losses by evaporation, regardless of other factors, the best place to build an underground dam in a river is the canyons that have the maximum area of the reservoir in upstream. Looking at the axes selected in the current research, it can be seen that the highest priorities and the most valuable axes are selected in the quaternary formations, which can indicate the accuracy of the structure's positioning. Since the peak of water consumption in the region is in the spring and summer seasons, therefore, by constructing an underground dam in the proposed sites, part of the water shortage and crisis in the hot seasons can be compensated.
Mohammad areza Ekhtesasi; Javad Chezgi; Maryam Khajavi
Abstract
Evaluation of watershed management projects today is one of the most fundamental issues being addressed in countries for future planning in the field of natural resource management projects. The results of evaluating watershed projects by presenting a strategy and strategy should reduce future problems ...
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Evaluation of watershed management projects today is one of the most fundamental issues being addressed in countries for future planning in the field of natural resource management projects. The results of evaluating watershed projects by presenting a strategy and strategy should reduce future problems and costs. In this study, hierarchical analysis method and SWOT analytical model were used to evaluate and present the strategy. In this study 4 main criteria (reduction of erosion, flood reduction, increase of vegetation covers and increase of sewage discharge) and 8 sub-criteria were used. Then the final weight of each criterion and sub-criteria were determined using Expert choice software. The results showed that erosion reduction criterion with relative importance of 0.482 had the most impact on watershed projects. SWOT model results in the region indicated that the region's conditions were in the fourth quarter, WT or defensive strategy. To this end, strategies for mitigating threats and addressing regional weaknesses were presented using the region's potentials and opportunities, and prioritized using expert opinions. 8 strategies were identified and evaluated based on the potential of the area and the evaluation of implemented projects. The best management strategies to build coastal walls around the gardens in collaboration with locals with a final score of 0.28 were the first priority and a strategy to improve and increase the height of the dam overflow. Constructed with 0.02 points was the last priority.
