RESEARCH ARTICLE Impacts of population growth and economic development on water quality of a lake: case study of Lake Victoria Kenya water Dauglas Wafula Juma & Hongtao Wang & Fengting Li Received: 11 October 2013 /Accepted: 6 January 2014 # Springer-Verlag Berlin Heidelberg 2014 Abstract Anthropogenic-induced water quality pollution is a major environmental problem in freshwater ecosystems today. As a result of this, eutrophication of lakes occurs. Population and economic development are key drivers of water resource pollution. To evaluate how growth in the riparian population and in the gross domestic product (GDP) with unplanned development affects the water quality of the lake, this paper evaluates Lake Victoria Kenyan waters basin. Waters quality data between 1990 and 2012 were analyzed along with re- views of published literature, papers, and reports. The nitrate- nitrogen (NO 3 -N), soluble phosphorus (PO 4 -P), chlorophyll a, and Secchi transparencies were evaluated as they are key water quality indicators. The NO 3 -N increased from 10 μgl -1 in 1990 to 98 μg1 -1 in 2008, while PO 4 -P increased from 4 μgl -1 in 1990 to 57 μgl -1 in 2008. The population and economic growth of Kenya are increasing with both having minimums in 1990 of 24.143 million people and 12.18 billion US dollars, to maximums in 2010 of 39.742 million people and 32.163 billion US dollars, respectively. A Secchi trans- parency is reducing with time, indicating an increasing pollu- tion. This was confirmed by an increase in aquatic vegetation using an analysis of moderate resolution imaging spectroradiometer (MODIS) images of 2000 and 2012 of Kenyan waters. This study found that increasing population and GDP increases pollution discharge thus polluting lakes. One of major factors causing lake water pollution is the unplanned or poor waste management policy and service. Keywords Water quality . MODIS . Eutrophication . Lake Victoria . Kenya . Water pollution Introduction Lake Victoria is the second largest fresh water lake in the world and the largest tropical lake with a surface area of 68,000 km 2 (average depth of 40 m and maximum depth of 79 m). The Lake is shared between Kenya, Uganda, and Tanzania, which controls 6, 45, and 49 %, respectively (Wang et al. 2012b). It is located between 3°S–0°30′ N latitude and 31°40′ E–34°50′ E longitudes at an altitude of 1,134 m above sea level. The Lake has a catchment basin area of 195,000 km 2 which includes Rwanda and Burundi. The catch- ment has a high human population density whose activities influence the lake intensively (Lung’ayia et al. 2001). Lake Victoria is of great socioeconomic significance to the riparian states as it is the major source of water for domestic, agricultural, and industrial purposes. The lake also provides a large quantity of fish for East African countries as well as for export markets in USA, Australia, European Union countries, and Israel (Muli 1996). Due to its strategic location of being shared by three nations, it acts as an avenue for transport. It is increasingly becoming a tourist destination for sport fishing, scenic beauty, and wildlife of the area. The lake has also a hydroelectric power plant that supplies electricity to Kenya and Uganda at source of the White Nile. With the economic relevance attached to the lake by ripar- ian communities, the Lake Victoria basin is one of the densely populated regions and has a rapidly growing population (Cohen et al. 1996). As the population and economy grows, the need of more natural resources leads to more resources being used than the ecosystem can sustain, thus impacting on the ecosystem negatively. A high population and economic developments have led to change in land use in the basin. The Responsible editor: Philippe Garrigues D. W. Juma : H. Wang (*) : F. Li Key Laboratory of Yangtze River Water Environment, Ministry of Education, State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China e-mail: hongtao@tongji.edu.cn Environ Sci Pollut Res DOI 10.1007/s11356-014-2524-5