Addressing storm water problems through low impact development (LID) in an urban area with resource constraints and tropical rainfall

Conventional stormwater conveyance controls collect stormwater from impervious surfaces, including roads, parking lots and rooftops, and transport the flow off site through buried pipes to treatment facilities or directly to receiving bodies of water. On the contrary, Low Impact Development (LID) is a multi-featured and essentially integrated form of development, modeled after nature and encompasses a variety of stormwater-management techniques. This research focused on the issue of transferability and worthwhileness of LID in developing countries where there are resource and other constraints and tropical rainfall characteristics. The research has tackled two main questions as applied to a real estate developed in an area called CMC in Addis Ababa, Ethiopia. ? Are LID strategies and structures transferable to urban areas of developing countries where there are financial, space and other constraints as well as tropical rainfall characteristics? ? Can LID strategies and structures be more cost-effective than the conventional strategies for addressing storm water-related problems in the already developed areas of the cities? The major activities performed during the research are Analyzing the catchment for constraints and opportunities, Analyzing the hydrology of the sub-catchments, Designing preliminary LID site that reduces the imperviousness of the area, Determining the LID storm water management requirements, Designing the conceptual LID site, Designing the detailed LID structures and Evaluating the cost-effectiveness of the LID design measures. A combination of imperviousness reduction and LID structures integration into the existing landscape was found to be more cost-effective than the existing conventional strategies to address storm water-related problems in the case study estate. Based on the results of the research, it can be concluded that LID strategies and structures are seemingly transferable to urban areas of developing countries where there are financial, space and other constraints as well as tropical rainfall characteristics. In addition, LID strategies and structures may be more cost-effective than the conventional strategies for addressing storm water-related problems in the already developed areas of the cities. It is recommended that further research should be conducted to analyze the cost effectiveness of the LID practice on areas that the aspects treated in this research