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arXiv · 2004.00710

A Stochastic Hydrological Model for Regulation of Lake Malawi Shire River system

Media Sehatzadeh·Nils Roar Saelthun·Jan Atle Roti
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Abstract

Located in Liwonde in the Southern Region of Malawi, Kamuzu Barrage is the only facility for regulation of water flow down Shire River, which has a major influence on water levels in Lake Malawi. In this article a hydrological model for optimized operation of the Kamuzu Barrage called the Kamuzu Barrage Operation Model (KABOM) is presented. This model is a tool for water resource management at the Kamuzu Barrage based on stochastic hydrology. The stochastic model uses water level readings at Lake Malawi and at the Shire River near Liwonde stretching from January 1900 to date. By using historical rating curves at Liwonde, and developing an updated post-2003 flood rating curve, the model can calculate flow at Liwonde for the entire period. The model simulates available water budgets for a range of probabilities based on the Lake Level and flow record over the past 115 years, plus available data on local inflows to the Shire River from its tributaries. The results provide a basis for choosing a release strategy in Kamuzu Barrage, which is used in optimizing the release at the barrage on daily basis. Resulting quantiles display a strong seasonal variation, highest Freewater forecasts within February and March in the rainy season, and the lowest months of June and July in dry season. The results for simulation are controlled against actual Freewater values in the period of December 2016 to October 2017, which demonstrates a satisfactory validation

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Media Sehatzadeh, Nils Roar Saelthun, Jan Atle Roti. 2020-03-28. A Stochastic Hydrological Model for Regulation of Lake Malawi Shire River system. https://arxiv.org/abs/2004.00710

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