The Ethiopian Road Authority (ERA) has included demonstration projects on the use of Otta seal surfacing under the Africa Community Access Programme (AFCAP). This type of seal is an alternative to the more commonly used chip seal and other more conventional surface treatments. The main project objectives in Ethiopia were to demonstrate Otta seal technology and to research the use of locally available materials.
Two sections of the road network were identified for inclusion in the demonstration project. One section 1900 metres in length was located at Combel village along the Tulubulo-Kela road and the other section 3000 metres long was located in the village of Gerado on the Combolcha-Mekaneselam road. This report deals with the construction of the section at Combel.
Overby, C.; Otto, A. Development of Design Standards for Low-Volume Roadsin Ethiopia. Otta Seal Demonstration project: Combel Village, Tulubolo-Kela RoadConstruction and Workshop Report. (2013) 45 pp.