Evaluation on the Integration of Road Network and Drainage System for the Occurrence of Flood: A Case of Bishoftu City

Abstract

The road networks are system of interconnected carriageways which are designed for transportation where their performances are influenced by proper provision of drainage system. This study has evaluated the integration of road network and urban storm water drainage system with the help of topographic map. The study particularly focused on flood prone areas with specific to main road and its feeding roads in Bishoftu City. The objective of this study was to evaluate the integration of road network and drainage system for the occurrence of flooding. Exploratory and descriptive types of research design with qualitative data type were used to describe and investigate the existing condition, coverage and level of integration of road and drainage system. Data collected using observation and interview for primary data source and document review for secondary data source were used to collect information and have been analyzed qualitatively. Interpretations have been done based on the common points and conceptualizing and explaining issues interrelated to one another in the themes. The analysis was mainly descriptive and the information collected from both primary and secondary sources were processed with the help of Microsoft excel, AutoCAD and ArcGIS software’s and the analyzed data were presented using tables, figures, chart, percentage, and graphs. The study was conducted from July to October, 2021 and strongly evaluated the integration of road and drainage infrastructure those feeding to main road for their causes to flooding and found that there is poor integration. Road surface drainage of the study area was found to be inadequate due insufficient road profile ranging from no cross fall to maximum of 1.5%, insufficient drainage structures provision, improper maintenance and lack of proper interconnection between the road and drainage infrastructures. The study recommended that there should be enough space for storm runoff to travel to its destination and conveyance channels as well as culverts should be adequately designed and properly reconstructed as well as regular maintenance of both road and drainage lines are found to be appropriate to mitigate the problem. City wide structural plan and urban flood drainage database management system has to be prepared in all sections of the road and drainage integration to solve the harmful impacts of flooding in city