The upgrading of the route between the port city of Walvis Bay and Swakopmund has been considered since at least the late 1990s when a feasibility study for the upgrade of the coastal road, TR2/1, was commissioned. A review of the study, including the preliminary design for upgrading of MR36 and MR44 (also known as road behind the dunes) to bitumen surfaced standards was concluded by SMEC in 2013.
The feasibility study, which included HDM-4 project analysis, found that an upgrade of MR44 would enable high volumes of especially heavy vehicles to be diverted from the coastal road. A key benefit would be a reduction in severe accidents on TR2/1 and reduced heavy vehicle traffic through the streets in Swakopmund.
The Roads Authority subsequently decided to upgrade MR36 and MR44 between Walvis Bay and Swakopmund to dual carriageway freeway standards. SMEC’s appointment was extended to include detailed design, contract administration and site supervision for the new 45 km long freeway (inland route) and 31 km coastal road rehabilitation and upgrade.
The design by SMEC includes six interchanges of various geometric complexity and seven prestressed interchange bridges. Other structures include five road-over-rail and two river bridges. Special technical challenges on this project include a very corrosive coastal environment causing reinforcing steel to rust much faster than usual, resulting in premature failure of bridges and culverts. Bridges and culverts were designed using a combination of mitigating measures, including construction using durable “W” concrete with ground granulated blast-furnace slag (GGBS) and coating with proprietary products to provide protection for the steel. What's more, natural mineral salts occurring in gravel used for construction can cause compaction loss in the pavement and upheaval of the seal. In order to successfully reduce the risk of long-term damage or premature failure of the seal and pavement, SMEC specified and are monitoring the implementation of rapid construction of layers to keep salt from crystallising at top of layers.
VKE, part of the SMEC group, was appointed in 2011 to carry out the feasibility study, preliminary design and subsequently the detailed design and contract administration for the upgrade to a dual carriageway freeway of Main Road 44 (MR44) and Main Road 36 (MR36), as well as the rehabilitation and upgrade for Trunk Road (TR)2/1 between Walvis Bay and Swakopmund.
The assignment includes project management, fieldwork, data collection and analysis, including survey, traffic engineering, geotechnical investigations, prospection and coordination of EIA and EMP development. Engineering design comprised of drainage design, geometric design, pavement design, structural design, design reporting and contract documentation. Contract administration of FIDIC Red Book contract and construction supervision are part of the engagement.
- Namibia, Erongo Region
- Technical Area:
- Roads Authority (Namibia)