International Journal of Emerging Technology and Advanced Engineering Website: www.ijetae.com (ISSN 2250-2459, ISO 9001:2008 Certified Journal, Volume 4, Issue 12, December 2014) 100 Assessment of Urban Drainage and Sanitation Challenges in Nigeria David O. Olukanni 1 , Rachael A. Adebayo 2 , Imokhai T. Tenebe 3 Department of Civil Engineering, Covenant University, P.M.B. 1023, Ota, Ogun State, Nigeria. Abstract— One of the observable impacts of rapidly growing urbanization and economic development in emerging cities of developing nations is witnessed in drainage problems connected to poor sanitation. The objectives of this research are to examine the causes and extent of damage on drainage and poor sanitation systems in urban areas, highlight measures to improve health and living conditions of the residents, and propose measures to improve the economic functioning of the cities. Six (6) Local Government Areas (LGAs) in Lagos State, Southwest Nigeria were selected. The descriptive cross-sectional study identified 50 respondents from each LGA through careful selection. Data were collected through validated questionnaire, thorough observations and interviews with residents. The result of the investigation shows that ineffective drainage systems are basically associated with poor maintenance, indiscriminate dumping of refuse in drains, erection of building on drainage channels and alignments that inhibit the flow of water which leads to critical environmental hazards. The study suggests new approach that could be used to achieve sustainable and effective sanitation which would support government’s effort in upgrading urban services by preparing plans and feasibility studies, improving drainage maintenance procedures and effectively manage human waste disposal. Keywords— drainage problems, environmental pollution, government, poor sanitation, private sector, public-sector, sustainable approach. I. INTRODUCTION The Rio declaration and the Agenda 21 from the early 1990’s introduced the concept of long-term sustainability of our environment. One important ingredient in the new approach is that technical, economic and social aspects of the development are handled carefully. There is today, a consensus that urban water systems should be approached in an integrated way. Surface water, groundwater, water quality, quantity, and ecology should be looked upon in relation to each other. Thus, the introduction of the concept of sustainability has, in the field of urban water systems among others, led to an increased interest for source control and open drainage of storm water within the urban environment (Geldof and Stahre, 2006). Presently, about 2.6 billion people are living without proper sanitation, of which Africa is not exempted (Olukanni, 2013a; WHO/UNICEF, 2012). The need to provide proper drainage and sanitation facilities is essential to match up with the ever increasing population growth (Banerjee and Morella, 2011). The increase in the population of a settlement and the attendant growth of the needs of the residents in both quantity and variety, bring about intensive exploitation of the resources of the environment. Such exploitation might increase to a level that the resources would not be able to sustain the population, and in some cases the environment would collapse resulting in serious environmental problems (Asoegwu, 2009). This is further buttressed by Belete (2011) who expressed that high urban population growth rate also results in drainage system challenges because an increase in population requires a proportionate increase in infrastructure (roads and drainage systems) of which when not properly catered for, the facilities will be imperfect. Also, inadequate integration between road and urban storm water drainage can be attributed to natural causes such as intense rainfall, flat topography and poor soil infiltration or man-made causes such as improperly laid and graded street, poor and inefficient drainage facilities that aggravate the flooding problem (Jimoh, 2008). Urban environments in Nigeria are faced with myriad of issues regarding poor drainage systems (Offiong et al., 2009) and water tight structures which are the major causes of flooding (Belete, 2011). Urban flooding which is the inundation of land or property in a built environment, particularly in more crowded areas are caused by rainfall overwhelming the capacity of drainage systems. Although this is sometimes caused by events such as flash flooding (Tucci, 2001). Urban flooding is a condition characterized by its repetitive and systemic impacts on communities whether or not the affected communities are located within floodplains or near any body of water (CNT, 2013). Sule (2001) described Lagos, Calabar and Ibadan as cities where houses are constructed directly on drain channels and that this practice has resulted to blockage of storm drains and consequently leading to overflow and flooding of streets.