The problem of urban informal settlements has occupied academic discourse for a long time. This study was carried out in Eldoret Municipality, Uasin Gishu District, and Rift Valley Province, Kenya. It examined urban informal settlements in respect to environmental planning and management within Eldoret Town. The rationale of the study is the emergence of the informal settlements and their resultant effects on the environment. The objectives of the study focused on mapping of land use/land cover changes in Huruma and Munyaka settlements within Eldoret the years 1989 to 2006, identifying the environmental problems and proposing possible solutions to the environmental problems. The mapping of land use/land cover changes was achieved using aerial photographs of 1989 and 2006. In Huruma settlement, results indicate that within the study period there was an increase of 10% in the built up area, while in Munyaka there was a massive increase of 56%. The recommendations made EMC are; provision of information on land use development to stakeholders, "citywide’ approach in the planning and management of settlements, integrated land management system and environmental awareness.