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Chapmans Peak - The Impossible Road

"A road linking Hout Bay and Noordhoek along the coast was impossible". That was the view of the commissioner of public works in a letter to the Cape Peninsula Publicity Association dated March 1910. Such a road, he insisted, would present "features of extreme difficulty, there being in one section over a mile of perpendicular cliffs to contend with." "These cliffs", he wrote, "drop for some two to three hundred feet sheer into the sea and deep water . . . it would appear that no passage over this portion is practicable, even on foot." Merely surveying the route had required men "crawling on hands and knees for long distances."

But some people don't take 'no' for an answer. Sir Frederick de Waal was elected Administrator of the Cape, a man who not only delighted in road building but was bloody minded enough to attempt the seemingly impossible. He hired a mining surveyor, Charl Marais, who employed a worker to chop footholds across the face and to hack out platforms on which to place his theodolite. In some places he was forced to suspend himself from a climbing rope and work like a fly on a wall.

Sir Frederick organised 700 convict labourers and sanctioned the project. Work began from the Hout Bay end in April 1915, and in June the following year from the Noordhoek side. Much credit for the daunting road must go to its engineer, Robert Glenday. With equipment which today would be considered extremely crude, and with unskilled and often unruly workers, he and his team chipped and blasted their way along the cliff face with dynamite, picks and shovels. Landslides were an ever-present danger, and remain a problem to this day. This road was completed in 1922 and they chiseled their victory message on the rocks, where it will now be preserved forever.

With this as a background, it would be interesting to speculate what the current EIA regulations would entail, if the proposal to build Chapmans Peak Drive was made today and not in 1910!

"Restoring Chapmans Peak and making it safer is difficult enough, but when the design brief is to change the alignment as little as possible and to minimise changes to the rock face environment, the challenge becomes a worthy test of engineering skill," says Willem de Vries seriously.

Willem is not normally serious; his face twinkles with delight as he describes passionately how the trials posed by the world-famous road are being overcome. "Yes, it does make things very difficult having to make the road safe and navigable for today's luxury buses using 80 year old standards that were better suited to a horse and carriage. Some alignments have radii around the 20m mark and many are transitional curves as well."

"But their layerworks were obviously outstanding. That road has taken an incredible battering over the years. Some of the rocks that have hurtled down the sheer cliffs weigh more than 4 tons, and there is maybe just a slight 300mm indentation where a sharp point was the point of impact."

Despite the onerous design restrictions, the renowned road so loved by tourists, marathon runners and cyclists will sport a number innovative and high tech designs and features. "I think it is the first time that half tunneling is being used in the country. This entails cutting into the mountain at road level, then moving the road in under the protection of the resulting overhang. In other places the solution used is to, build a concrete canopy that will ensure that any rocks that do fall off the mountain will at worst land close to the old rock faced guard wall, while traffic will travel safely under the canopy," Willem says animatedly.

"New rock catch fencing technology will also be used for the first time. When the road is opened again in 2004, it will still look like largely like the original road. There will be no lighting and stone faced barrier walls are to be used in place of the more modern guardrails. The significant changes will be limited to just the few sections where we have to use the canopies and the half tunnel. None the less this will now be a hi-tech road, with a new speed limit of 20 to 40km per hour with sophisticated information signage and CCTV cameras to monitor the traffic."
 
Chapmans Peak Driive | SSI Consulting Engineers


"It has been exciting working with the consortium partners. I have experienced new and different perspectives from them. I have been busy with the project on and off for about 2 years now. This project is naturally a high profile one that has stirred emotions from a wider range of concerned groups. I have managed to steer clear of attending the public forums, concentrating rather on dealing with statutory issues. We are still busy with the project and I'm sure that there are still many hurdles to overcome."



"The road is only 10km from Hout Bay to Noordhoek. But in that short stretch, I have 114 PI's. Using the TURN module has been a great help. I was one of the first people to talk senior Knowledge Base developer Dawid du Toit into writing the code for this great piece of software."

"For instance, there is now a proposal to allow the new TATABUS 35-seater taxis to travel from Noordhoek to Hout Bay - the opposite direction to the big 12.5m tour buses. With TURN, I can easily see if they can pass each other along the entire stretch of road."

"It is a privilege to work on a road like Chapmans Peak. I am working with a team of people here at Stewart Scott, Janine Conner and John Hendricks. The team at Knowledge Base have also been involved, with great support. I enjoy using the program and getting the support that I need. On a job like this, you need all the help you can get - or you could end up going round the bend," says Willem with that shining smile.

An interesting man on an interesting project in interesting times! "It is, after all, one of the most beautiful coastal roads in the world."

image Willem de Vries studied Mechanical Engineering at Technikon Pretoria, where he graduated in 1984. After a short spell at Iscor, Willem found himself in the Electrical Engineering department at the Newcastle Municipality. In 1987, he joined the then Scott & De Waal in Bloemfontein, and is still there. His passion lies in the IT industry; he does all the IT work in Cape Town and other offices.

 
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