Heritage Cases

It is proposed that an existing, damaged low-level stream crossing be upgraded in order to improve access between Ga-Mampa village and surrounding towns and transportation routes. Currently, access is regularly cut off for a few days at a time, when the river floods following heavy rainfall. Furthermore, erosion protection is required to control the erosion around the access bridge, as the whole area is known for its severe erosion due to poor soil conditions. The design proposed by the engineers for the upgrading of the bridge includes extensive erosion protection, and the bridge has been designed to accommodate the 1:20 year flood. The project is proposed to consist of the following: - Construction of a low-level access bridge which will allow the river to flow underneath the structure. - Erosion control measures immediately upstream and downstream of the crossing. - Providing drainage channels along the road to channel storm water. - Re-gravelling of the road leading towards the bridge on both sides. - Adjustment of the vertical alignment of the road, and construction of the road as a class 3 road (only the section forming part of the project site on both sides of the bridge). - Providing pedestrian access on the bridge. - Four weirs (two upstream and two downstream) for further erosion protection. The bridge is proposed to consist of 4 culverts of 3mx3m each. Gabions, reno mattresses and dump rock is proposed to be installed on the upstream and downstream sides of the bridge for the purpose of erosion protection. Furthermore, four weirs (two upstream and two downstream) are also proposed for further erosion protection, as the geotechnical study indicated a need for this due to the severe erosion risk in the area.