Minkah Richard
Department of Statistics, University of Ghana, Accra, Ghana.
Springerplus. 2016 Jan 29;5:96. doi: 10.1186/s40064-016-1719-2. eCollection 2016.
Assessing the probability of very low or high water levels is an important issue in the management of hydroelectric dams. In the case of the Akosombo dam, very low and high water levels result in load shedding of electrical power and flooding in communities downstream respectively. In this paper, we use extreme value theory to estimate the probability and return period of very low water levels that can result in load shedding or a complete shutdown of the dam's operations. In addition, we assess the probability and return period of high water levels near the height of the dam and beyond. This provides a framework for a possible extension of the dam to sustain the generation of electrical power and reduce the frequency of spillage that causes flooding in communities downstream. The results show that an extension of the dam can reduce the probability and prolong the return period of a flood. In addition, we found a negligible probability of a complete shutdown of the dam due to inadequate water level.
评估极低或极高水位的概率是水电大坝管理中的一个重要问题。就阿科松博大坝而言，极低和极高水位分别导致电力负荷削减和下游社区洪水泛滥。在本文中，我们使用极值理论来估计可能导致负荷削减或大坝运营完全停止的极低水位的概率和重现期。此外，我们评估大坝高度附近及以上的高水位的概率和重现期。这为大坝的可能扩建提供了一个框架，以维持电力生产并减少导致下游社区洪水泛滥的溢流频率。结果表明，大坝扩建可以降低洪水的概率并延长重现期。此外，我们发现由于水位不足导致大坝完全关闭的概率可以忽略不计。
