Plotting the river

Whenever I plan a cycle trip, I purchase a map of the intended route, add up the distances to see where I will have stop over’s and I am on my way. From Jo’burg to Cape Town it is easy. There is only one road and the towns are spaced out a day’s cycle apart. Through North Western Europe; I had a map that covered the entire area and thus did not give enough detail. Still all I did was write down the names of the towns I would be passing through to my destination. Here in South Africa the towns are roughly 70 km apart. In Europe you could pass through up to 5 towns in the same distance. No need to worry too much about where north, east, south or west is.

One would expect to have less map work when kayaking down a river. The Orange River flows East-West across the country. That is the only route one can go on the river, no detours and as the river flows, one cannot do anything but go with the flow: then why all this map work?

Unlike on the roads, there are no distance markers on the river. If one does not work out the distances kilometre per kilometre, you will have no idea of how far you have come or still need to go. No sign that says: 10kilometers to Orania. Without some kind of distance markers, one can very easily under-estimate what one has done for the day and then fall behind schedule. This can have dire consequences on when the journey is completed, but also raise false alarms regarding one’s safety.

The weirs are marked on the Topo maps, some rapids, one waterfall, no whirlpools and a handful of siphons. Apart from the Augrabies Waterfall, there is another 5 smaller (10 – 30m) waterfalls along the river. Marcel’s Monster, the Hubbly bubbly, Hells Gate and the Ritchie Falls, for example, are not marked on the maps. The only information is what one can find from websites that make reference to them or speaking to people, like Robbie Herreveldt, that has kayaked the non-commercial portions of the river. Then one can get some guestimate of where some of these danger points are. Knowing where you are and how far to go before getting sucked into a whirlpool can mean the difference between life and death.

As whirlpools and waterfalls are not marked, it is critical that one has to literally study the map with a magnifying glass. Whirlpools can be found in areas where there is a sudden narrowing in the river that is not caused by sand banks. Like the entrance to a gorge or a gully. The force of the water flowing into the narrow area stays proportional to the amount of water flowing out. However, because of this force, the sudden ‘blockage’ caused by the narrowing banks, causes the water to whirl back on itself. If the water level does not increase, one can get stuck in a whirlpool for a couple of hours before the whirlpool belches you out, when the equilibrium is reached by the water flowing out through the narrowing. The worst I heard was of a kayak stuck in a whirlpool for two weeks!

Waterfalls or potential waterfalls are identifiable by contour lines that cross the river. These are not so easy to spot. When one looks at the Augrabies Waterfall, it is very easy to see the contours crossing and very close to each other. Thus indicating sheer cliffs and the falls, however the other 5 falls could be 1, 2 or 3 contour lines not so close to each other. If info is available on the web or from a farmer along the way, the distance markers can make it so much easier to find these falls and make plans for portaging.

Another useful preparation one can do is to work out the navigation points. This comes in especially handy when crossing dams the size of Lake !Gariep or Van der Kloof. As this mass expanse of water, does not run in a nice straight line, it is very easy to take the wrong turn and end up in a dead end bay. A lot of time can be wasted trying to find the right line to continue or climbing kopjes to see where one is suppose to go. Some of this wasted time can be saved by marking navigation points on the map up front.

It is done by placing the baseline of the compass in the direction you want to go. Then align the north indicator with the magnetic north needle. The degree of variation between the baseline and the north needle gives one an indication in what direction one should go. Off course for this to work, one still has to know where one is in relation to the map. Thus one must be able to position oneself to the environment to ‘read’ the correct navigation point.

Once the entire distance is marked out in 1 kilometre intervals, it is then marked with 10 kilometre markers. This helps to see at a glance a bigger picture of distances covered. Placing the longitude and latitude values at these points also make it useful in case of an emergency. Thus if help is required, the closest GPS coordinates can be given immediately.

But I have 70 1:50 000 Topo maps. It is not possible to carry this amount of maps. The maps must still be cut down to useable sizes and pasted together as there are a number of maps that only have a small portion of the river on them. Before this is done useful information like nearest farms, towns, roads etc must be marked on the portions that we will be taking with.

A lot of preparation work upfront that can save a lot of time whilst on the river. For now we do not have GPS’s, but still good old map work comes in handy when the GPS is out of battery power or fine tuning locations and distances.

Once all this information is collated, a schedule can be worked out on how long it will take to get between towns and complete the journey.

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