Assessing the performance of Kiwunya drainage channel in Kampala.

Abstract

This project attempts to assess the performance of Kiwunya drainage channel in Kampala. This channel was constructed two years ago but it still experiences flooding in some areas during heavy down pour therefore, the findings and measures can be used to improve its performance. Also sediment transport into the channel and solid waste deposits into the channel not only does it reduce the conveyance capacity of the channel but also causes health hazards to the community. The objectives of the study were to determine the hydraulic performance of the channel, determine the peak run off from the catchment, determine the effect of sedimentation on the conveyance capacity of the channel and the development of an operation and maintenance strategy of the channel. We come up with an appropriate assessment of the Kiwunya channel to examine its hydraulic performance as a factor from the multi-criteria approach. A reconnaissance survey was conducted which involved visiting the site and interactions with the community about the performance of the channel. An ArcGIS software was used in the generation and measurement of the channel’s catchment area. The 10-year return-period design storm was determined with the aid of rainfall data for the catchment. The time of concentration was calculated as 5 minutes, the critical rainfall intensity was read off from the developed intensity-duration-frequency curves and the peak runoff calculated from EPA-SWMM as. In this report the sedimentation effect on the channel conveyance capacity was also determined by using the universal soil loss equation (USLE) which determines the estimate sediment quantity that is likely to go into the channel thus reducing its conveyance capacity throughout its design life. operation and maintenance strategy of the channel was also carried out in this report in order to see how the drainage channel can have smooth operation for its design life. After carrying out the analysis, recommendations to ensure that all the project objectives are met were explained such as proper solid-waste management, regular desilting of the channel, and strict law enforcement on unplanned residences built along the channel, among others.