I knew about this place.  Well, sort of.  If you fly over it, so to speak, in Google Earth, there it lies in all their glory. Not that one really believes it either, for according to the tenets of Davis, this doesn’t fit into the model as we were taught.  

This was confirmed in our first-year lectures when our old professor (he seemed positively ancient from our 19-year-old perspective) took as through several weeks of lectures titled ‘Surface Processes’ which was just a fancy name for fluvial hydrology and geomorphology.  In those lectures we learned about deltas, meanders, levees, all stuff that some of us had learned about before.  The latter features were characteristic of the ‘old age’ of the river, when energy levels were down and deposition was dominant. 

The great Mississippi River was the perfect example of a river in its grand old age, languidly meandering across a vast floodplain in self-confident, glorious curves, whilst the US Army Corp of Engineers valiantly tried to keep her under control, cajoling her here, propping her up there, desperately stemming impetuous outbursts here and there. No one wanted those muddy waters gushing across the landscape and inundating towns and farmland. And at the end of that riparian journey an outpouring into the Gulf of Mexico to form a delta which is also a wonderful case study which delighted sedimentologists everywhere

According to Davis, rivers pass through three stages, namely, youthful, mature and finally old age.  This is how things are supposed to be.  Unless of course there is some kind of rejuvenation – a kind of geographical elixir of eternal youth injected into the landscape by some external factor.  These concepts had been introduced to us whilst we were at school, and continued through into university, where our old geology professor lectured us on these things.

Not enough wood to hang a man

We did learn some additional things including the lack of soil cover on limestone karst terrane in Ireland, which prompted Edmund Ludlow, Cromwell’s second in command to remark, “It is a country where there is not enough water to drown a man, wood enough to hang one, nor earth enough to bury him." Not much to do with meanders and geomorphology, but I guess one hopes to get a rounded education when showing up at university.

You must also remember that we were sitting in the same lecture theatres where Lester King had propounded his theories on landscape evoloution for generations of students.  And as we all know; King claimed to be the greatest geomorphologist in the world.  

Geomorphology had been the ascendant creed

A claim not without merit I might add. Geomorphology had been the ascendant creed of that department for many years and King’s ghost still haunted those corridors. King’s theories of pediplanation were a response to Davis’s theories of peneplanation – which the various stages of a river being part of his grand theory of landscape development.

I went looking for local examples of meanders to share with you, knowing that due to the elevated nature of our topography, we don’t have those well-developed flood plains that are to be found elsewhere. I had found amazing meander systems on the Chobe River between Botswana and Namibia some years before, but now I needed something to share with you that was closer to home.  

So, what did I find? You guessed it – meanders.  Flopping about a flood plain 15 km from my house, and perched 1000 m above sea level – and flying in the face of Davis’s theory.  There they lay in all their wandering glory – displaying all the features of a typical flood plain, with oxbow lakes and meander scars to boot. 

What is amazing though is that less than 1.6 km from that last meander, the river begins to splash its way over a series of rapids, before tumbling over a 10 m high cataract, and then ultimately plummeting over a 105-metre-high waterfall.  And we are still 100 km from the sea. So much for the Davisian notions of youth, maturity and old age – here over a very short distance, the river goes from ‘old age’ characterised by low-energy meanders, into a plume of tumbling white water – youth personified – which then cascades its way down a series of rapids at the base of a deep gorge.

Fly the drone over them

I thought that the best way to share these meanders with you was to fly the drone over them.  So, I plonked down some place-marks on Google Earth of localities where I could get access. On closer inspection I realised that I knew some of these places and had in fact driven over a number of the small bridges on previous travels.

My aim was to get the drone high up, so that we could get a bird’s eye view of those beautiful bends which the drone was going to show off to perfection. Crossing those bridges gives no hint of the meanders that lie upstream and downstream of the crossing. This time I knew what I wanted, and so I hacked my way down some farm roads until I arrived at an old wood and iron bridge, with a metal stake sticking out of the river, topped by a sign saying “Flood Level, 1987” – the level being about 1.5 m above the bridge deck. 

Reed-fringed oxbow lakes

A river flowing below a bridge is not an uncommon sight, but not 20 metres from where I was parked was an oxbow lake - quiescent, muddy and full of reeds.  Another short drive brought me to another crossing, with a flowing river and reed-fringed oxbow lakes nearby much like the previous place. 

The low sun was throwing long rays of golden light as the blustering wind tugged and twirled amber cascades of autumnal leaves off the trees and bent the reeds in the fen. I was reluctant to put the drone in the sky thanks to those gusty conditions. Drones fly downwind particularly well, but make heavy work of the trip home, particularly when battery levels are low. I was worried that my drone may have got lost in a muddy oxbow lake, to be buried in sediment to become one with the geological record for eternity.

Dolerite intrusions that have baked the surrounding rocks

Back home I pulled the geological map into Google Earth, and there, plain enough for us all to see, are the meanders, the alluvium, the rapids where the river passes from alluvial cover to sandstones of the Volksrust Formation. What’s more, the map shows dolerite intrusions that have baked the surrounding rocks, making them more resistant to erosion – one of the reasons for the 105 m high Karkloof Falls.

So, we have another adventure ahead of us yet, this time perhaps in the embrace of a frosty dawn to avoid those afternoon winds. Looking forward to having you along on the adventure.