Newsletter 7

Newsletter 7

17th December 2022

My latest explorations took me to the south of Dunedin, with a short list of places to try and explore.  First on the list was a coal mine in the Taratu Formation - that layered piece of geology in the hills along the coast south of Dunedin.  I'd seen the place on old maps and there seemed to be something worth investigating.

At the end of the road - well, the end of the road I felt safe to drive on - I walked towards the mine site, plantation pines on the right and the remains of those recently harvested on the left.  At a skid site were a couple of utes and some men in fluro vests.  No getting past them today and I'd rather be doing this with permission in any case.  

We had a chat and my next move to get onto the mine site will be to talk to the forestry company.  All good, and I was told there was something worth finding down the road.

Next on the list was an old white-painted building, visible from the road from SH1 to Kaitangata.  I knocked on a couple of doors and was told which door to knock on.  A chat with the landowner got me permission to explore the building, which is an old dairy.

The place was ion reasonable condition for its age - with locally-fired bricks and old cement there has been some erosion.  A nearby offal pit, overflowing from recent rain, added a distinct atmosphere to the place.

Next on the list was something I'd seen almost as many times as I'd travelled through the Manuka Gorge to Central Otago - and that's more then a few.  At the end of the Gorge is a tunnel, now reopened as part of a cycle trail.  Out of the tunnel, and now beside the road, is a pipe from which water could fill the tanks of steam locomotives on the Roxburgh branch railway line.  For a little while recently I'd been wondering where that water came from.  The last time I'd been there with a little time to spare I'd had a look above the pipe and found the concrete tank which held the water.  I knew that you could look down into the stream bed from the other side of the highway and see the pipe which fed the water over the stream, under the road and into the tank.  But where did the water come from?

I looked for and found a passable way down from the road and into the stream bed.  Crossed the stream under the pipe and followed its line up the opposite slope through the forest.  Very soon I found that the forest growth obscured my view, so I began to make my way downhill and upstream, with the idea that, sooner or later, I might find an intake weir for the system.

I've seen similar feeds on the Central Otago line.  One feature of them is that they had a continual supply of water, with an overflow outlet from the header tank, to prevent the system freezing up in frosty weather.  So I was looking for some kind of intake at a height above that of the concrete tank.

I encountered a side-stream of Manuka Creek and followed it up, finding a beautiful little waterfall on the way.  To get around the waterfall I had to sidle around a steep, damp area where my ice axe was useful.  Arriving at the top of the the waterfall, I found it.  The remains of some kind of stone weir - barely recognisable - and a water race heading off towards where the pipe meet it up the slope from where it crosses the stream.

I followed the race along the hillside and found a concrete block with a tap and a pipe which headed downhill in the right direction and at the right place to be the water feed.  But the race continued and I followed it.  Eventually it ended in a cliffed area with what seemed to be a road or track below.  Maybe it was taken by a pipe or flume around the cliffs to - where?  Maybe I'll head back some day and find out where.