The Open Environmental Engineering Journal

2012, 5 : 66-76
Published online 2012 July 13. DOI: 10.2174/1874829501205010066
Publisher ID: TOENVIEJ-5-66

Modelling the Impact of Land Use Changes on Sediment Loading Into Lake Victoria Using SWAT Model: A Case of Simiyu Catchment Tanzania

R. J. Kimwaga , F. Bukirwa , N. Banadda , U. G Wali , I. Nhapi and D. A. Mashauri
Department of Water Resources Engineering, University of Dares Salaam, P. O. Box 35131, Dares Salaam, Tanzania.

ABSTRACT

This study aimed at characterising the land use in the Simiyu catchment of Lake Victoria and using land-uses of 1975 and 2006 and comparing the relative impact of land-use change on sediment loading into the Lake. Remote sensing using the package ILIWIS 3.0. was used to identify and characterize the land-use while Soil and Water Assessment Tool (SWAT) was used to quantify sediment loading from the 1975 and 2006 land-use scenarios. The results of this study indicate that there was an expansion of agricultural land from 19.33% to 73.43% of the catchment at an annual change rate of 2.9%. Furthermore, the land-use of 1975-yielded less sediment loading compared to that of 2006. Model simulation at the catchment outlet for sediment reported a total yield of 98,467 tons/yr while the actual measured sediment loading had the value of 2,075,114 tons/yr. Hence, the model underestimated sediment yield in the catchment. With good model performance, developing management plans to control sediment loading into Lake Victoria can be achieved using the SWAT model.

Keywords:

Land use, sediment loading, SWAT modelling.