Abstract:
This thesis presents results of the assessment of drainage structures; performance on Katerema Pajwenda gravel road in Mulanda sub county region and redesign measures. Redesign measures were proposed based on UNRA drainage design manuals 2002 and 2011 for Low Volume Roads.
Descriptive and exploratory methods of research were used for this thesis work. Field visits of the catchment area that contributes runoff to the drainage structures were made and the existing problems were described.
The necessary secondary data for this research are land cover map, topographical map, geological map, and feasibility study of the road before construction. The primary data are photographs that show the existing drainage structures conditions, flood level marks and information that is gathered from the residences and road desk office about the performance of the drainage structures during the rainy season. Hydrological analysis was carried out by using Rational and SCS equations. Hydraulic parameters are determined by using Manning’s equation.
Structural and hydraulically failures of drainage structures and roadways were investigated. Moreover. stations of the road were investigated that require construction of minor drainage structures but not constructed.
Suitable mitigation measures were proposed in order to make the road and drainage structures serve for the intended purposes sustainably. New drainage structures were proposed where they are lacking in the existing system.
