The lake has a surface area of 139 sqkm , "THE OUTFLOW OF LAKE NAIVASHA BASED ON THE STABLE ISOTOPE COMPOSITION" (characteristics), M.K. Arusei, J. K Sanga, M.P Tole, Department of Chemistry, School of Environmental Studies, Moi University, P.O Box 3900 Eldoret, Kenya, webpage:UNEP-Moi-Arusei-PDF