Analysis of River Tributaries’ Streamflow Contribution Using WEAP Model: A Case of the Ngwerere and Kanakatampa Tributaries to the Chongwe River in Zambia  

作　　者：Tewodros M. Tena Frank Mudenda Alick Nguvulu Phenny Mwaanga John M. Gathenya Tewodros M. Tena;Frank Mudenda;Alick Nguvulu;Phenny Mwaanga;John M. Gathenya(Department of Environmental Engineering, The Copperbelt University, Kitwe, Zambia;Department of Civil Engineering, University of Pretoria, Pretoria, South Africa;Department of Civil and Environmental Engineering, The University of Zambia, Lusaka, Zambia;Geomatics Engineering Department, The Copperbelt University, Kitwe, Zambia;Department of Soil, Water and Environmental Engineering, Jomo Kenyatta University of Agriculture & Technology, Nairobi, Kenya)

机构地区：[1]Department of Environmental Engineering, The Copperbelt University, Kitwe, Zambia [2]Department of Civil Engineering, University of Pretoria, Pretoria, South Africa [3]Department of Civil and Environmental Engineering, The University of Zambia, Lusaka, Zambia [4]Geomatics Engineering Department, The Copperbelt University, Kitwe, Zambia [5]Department of Soil, Water and Environmental Engineering, Jomo Kenyatta University of Agriculture & Technology, Nairobi, Kenya

出　　处：《Journal of Water Resource and Protection》2021年第4期309-323,共15页水资源与保护（英文）

摘　　要：Ngwerere and Kanakatampa Streams are the main tributaries of the Chongwe River. The Ngwerere stream originates from the city of Lusaka and meanders through Lusaka City and Chongwe Town for an approximate distance of 41 km before joining into the upper part of Chongwe River. The Kanakatampa Stream is a tributary of the Chongwe River. It meanders from the Kanakatampa Area for approximately 52 km before discharging into the middle of the upper part of the Chongwe River. The Chongwe River Catchment which is a sub-catchment of the Zambezi Basin drew the attention of researchers and policymakers when the Chongwe River started drying up in the dry seasons causing a water crisis particularly in the downstream regions of the middle catchment. Therefore, it is important from the water resources management perspective, to assess the contribution of tributaries into the flows of the Chongwe River. Ngwerere and Kanakatampa streams are socially, economically, and environmentally important streams for the city of Lusaka and surrounding area. This study, therefore, concentrated on evaluating the flow contribution of the two streams to the Chongwe River using the Water Evaluation And Planning (WEAP) tool. The streamflow data (1970-2010) recorded at the Chongwe Great East Road Bridge gauging station were used in the WEAP embedded Parameter ESTimation (PEST) auto-calibration tool to calibrate (1970-1999) and validate (2000-2010) the model. The monthly streamflow model calibration and validation results were assessed using the correlation coefficient (CC), Coefficient of determination (R²), Nash-Sutcliffe Coefficient of Efficiency (NSE), and Percent bias (PBIAS). The model performance results achieved were PBIAS of 1.24%, CC = 0.81, R² = 0.66 and NSE = 0.62 during the calibration period and a positive PBIAS of 2.94%, CC = 0.81, R² = 0.67 and NSE = 0.62 during the validation period. The median of the flows (Q₅₀) was obtained from the historical flow duration curves (FDCs) generated in averaNgwerere and Kanakatampa Streams are the main tributaries of the Chongwe River. The Ngwerere stream originates from the city of Lusaka and meanders through Lusaka City and Chongwe Town for an approximate distance of 41 km before joining into the upper part of Chongwe River. The Kanakatampa Stream is a tributary of the Chongwe River. It meanders from the Kanakatampa Area for approximately 52 km before discharging into the middle of the upper part of the Chongwe River. The Chongwe River Catchment which is a sub-catchment of the Zambezi Basin drew the attention of researchers and policymakers when the Chongwe River started drying up in the dry seasons causing a water crisis particularly in the downstream regions of the middle catchment. Therefore, it is important from the water resources management perspective, to assess the contribution of tributaries into the flows of the Chongwe River. Ngwerere and Kanakatampa streams are socially, economically, and environmentally important streams for the city of Lusaka and surrounding area. This study, therefore, concentrated on evaluating the flow contribution of the two streams to the Chongwe River using the Water Evaluation And Planning (WEAP) tool. The streamflow data (1970-2010) recorded at the Chongwe Great East Road Bridge gauging station were used in the WEAP embedded Parameter ESTimation (PEST) auto-calibration tool to calibrate (1970-1999) and validate (2000-2010) the model. The monthly streamflow model calibration and validation results were assessed using the correlation coefficient (CC), Coefficient of determination (R²), Nash-Sutcliffe Coefficient of Efficiency (NSE), and Percent bias (PBIAS). The model performance results achieved were PBIAS of 1.24%, CC = 0.81, R² = 0.66 and NSE = 0.62 during the calibration period and a positive PBIAS of 2.94%, CC = 0.81, R² = 0.67 and NSE = 0.62 during the validation period. The median of the flows (Q₅₀) was obtained from the historical flow duration curves (FDCs) generated in avera

关 键 词：Ngwerere Stream Kanakatampa Stream Chongwe River Zambezi Basin WEAP Model Water Resource Management PEST 

分 类 号：F42[经济管理—产业经济]