African Journal of
Environmental Science and Technology

  • Abbreviation: Afr. J. Environ. Sci. Technol.
  • Language: English
  • ISSN: 1996-0786
  • DOI: 10.5897/AJEST
  • Start Year: 2007
  • Published Articles: 1126

Full Length Research Paper

Determining and modeling the dispersion of non point source pollutants in Lake Victoria: A case study of Gaba Landing site in Uganda

N. Banadda1*, I. Nhapi2 and U. G. Wali3
  1Agricultural and Bio-Systems Engineering Department, Makerere University, P. O. Box 7062, Kampala, Uganda. 2Civil Engineering Department, University of Zimbabwe, Box MP 167, Harare, Zimbabwe. 3Department of Building and Civil Engineering, National University of Rwanda, P. O. Box 117, Butare, Rwanda.
Email: [email protected]

  •  Accepted: 31 January 2011
  •  Published: 30 March 2011

Abstract

 

Lake Victoria is an important source of livelihood that is threatened by rising pollution. In this study, pollutants in runoff are characterized and their dispersion after they enter the lake is measured and modeled at different points in the study areas. The objective is to develop a one dimensional mathematical model which can be used to predict the nutrient (ammonia, nitrite, nitrate, and phosphate) dispersion distances within the lake. A comparison between rain period nutrient concentrations and dry period nutrient concentrations within the Lake showed an elevation in nutrient levels during the rainy season, with exception of nitrate. However, nitrate had high levels during the dry season. Ammonia was found to disperse to horizontal distances of 38 m; nitrite 45 m, with nitrate and phosphate each attaining distances of 34 m. Measured nutrient concentration within the Lake compared well with model estimations.

 

Key words: Modeling, water quality, nutrients, lake Victoria.