By Anél Powell
In a R1,2-billion upgrade, the Huguenot tunnel on the N1 toll road linking Paarl to Du Toit's Kloof in the Western Cape is to double in size, with a second tunnel, a new two-lane road and a new bridge over the Elands River.
A traffic analysis flow study in 2005 warned then that the tunnel was already reaching capacity during peak periods.
According to CCA Environmental, which has prepared a draft basic assessment report for the Department of Environmental Affairs and Tourism, the upgrade will improve the efficiency of the national road network "through the increased capacity of the tunnel to accommodate increased traffic flows".
Each tunnel would have two unidirectional traffic lanes.
The South African National Roads Agency Limited (Sanral) said construction would probably start in 2010 and would form part of the N1/N2 Winelands toll highway project.
It is estimated the project would contribute an extra R963 000 annually in toll income and would have an expected capital value of R1.2bn.
More than 200 new jobs will be created for a six-month construction period and an additional 280 permanent jobs when the tunnel was complete. This would include the 30 posts related to the operation of the tunnel and the 250 staff needed for maintenance.
A second tunnel or northern bore already exists at the site, and cuts through 4km of the mountain. This northern bore tunnel was constructed between 1984 and 1988 when the existing southern bore tunnel was built. CCA said the Du Toit's Kloof tunnel was always intended to be a twin- tunnel operation.
This system is a safer option as it allows for better traffic control and reduces the impact of an accident or fire. The use of two lanes also makes it easier to maintain the tunnel.
The increase in traffic volumes and concerns about the safety of the 20-year-old tunnel had prompted Sanral to complete work on the northern bore tunnel.
A new two-lane road will be built to the north of the road to take eastbound traffic into the new tunnel.
While the new tunnel will look the same as the tunnel that has been in operation since 1998, CCA Environmental said the second tunnel would have improvements to the ventilation and emergency evacuation routes.
The tunnel will be redesigned to allow fresh air ventilation so that the level of vehicle exhaust emissions would be kept within international safety and health standards.
Once the second tunnel was completed, the ventilation and evacuation systems of the old tunnel would be upgraded. Each tunnel will get its own power supply so that each route will have independent power should there be a problem in the other tunnel.
CCA Environmental said that if the second tunnel was not completed, the continued rise in traffic volumes through the toll road would affect the safety of motorists. Excessive vehicle emissions would affect the maintenance of the tunnel and the quality of the air.
The erosion that would result from construction on the Elands and Molenaars rivers would be limited to parts that had previously recovered well from similar work.
Sanral has not yet consulted the Drakenstein Municipality before drafting the basic assessment report. The municipality will be invited to comment on the draft before a final assessment report was compiled.
Meanwhile, the draft basic assessment report of the project has been advertised to inform road users of the proposed upgrade.
CCA said there would not be any public meetings about the project as the upgrade was planned on an existing section of the national road network. Comments have not yet been received.
Interested and affected parties have until October 8 to comment on the proposed changes to the tunnel. The final basic assessment report, including comments and concerns, will be submitted to the Department of Environmental Affairs and Tourism for consideration.