Yilma, Sileshi (PhD)Kajubi, Enock2022-03-092023-11-042022-03-092023-11-042019-07http://etd.aau.edu.et/handle/123456789/30511The flooding problem along the magenagna-Ayat Addis Ababa Light Rail Train line has persisted since its construction. Therefore, flood analysis has been carried out as well as the hydraulic competence of the existing drainage structures along the line. Flood frequency analysis was carried out using the Gumbel distribution after best fit tests and the design storms that correspond to the 25, 50, 100 and 200-year return periods were computed. Using a high resolution Digital Elevation Model (DEM) of 12.5m, a watershed delineation was carried out and the sub-basin parameters calculated accordingly. A total of seven (7) watersheds fourteen (14) sub watersheds were obtained in project area. The drainage basins ranged between 1.02sq. Km for catchment six to 10.27 sq. Km for catchment five. Using the watershed parameters obtained, time of concentration, lag time and the storage attenuation coefficients were computed for each sub-basin to be used in the hydraulic computations. A rainfall-runoff transformation was carried to assess the hydraulic competence for the existing drainage structures for 25-year and 50-year return period for all culverts and 50-year and 100-year return periods for the bridges. One culvert was found over designed, three under designed, two inaccessible on site and one competent as well as the bridge. Poor interoperability between the railroad grade and the highway grade at the level crossing was identified as one of the major causes for flooding at level crossings thus must be redesigned. Transverse aggregate drains as well as silt traps in the longitudinal railroad side drains have been proposed, jointing of the railroad drainage system with the road system, public sensitization towards municipal solid waste management and establishment of a railway drainage asset management policy have been recommended to mitigate the and improve the infrastructure drainage to be safe, sustainable and resilient.en-USFlood analysisHydraulic competenceRailway level crossing drainageThesis