Searching a section of hillside for the water race and following forgotten tracks
The plan for today had been to tackle one of two big expeditions I have been wanting to do for quite some time. Unfortunately, I got away later than expected and also had to be home earlier than planned. That ruled out anything too ambitious, so while heading towards Wainuiomata I started thinking about somewhere easier that I could explore.
I decided to head to the Hine Road Recreation Area car park and explore a section of hillside where, despite several previous searches, I have never been able to find any definite sign of the old Wainuiomata water race.
For some time I have been trying to work out exactly where the race runs through this area and, in particular, to solve the mystery of a trench that curves around a spur above or below it. I suspect the trench may be part of the old water race access track, which ran above the race and provided access to the manhole entrances. On an earlier bush bash I followed what appeared to be this track around the spur, only to find myself walking directly into the mysterious trench which I do not think was a coincedence.
Further east is another clue: an old wooden post standing beside the track. It looks as though it may once have held a sign or marker, so the idea today was to search both areas more carefully for any evidence of the buried race.
I first headed to the Scour Pipe, part of the Orongorongo Pipeline system, and from there followed the trench. I cleared away some loose rocks and debris in likely-looking spots, but found nothing. I then continued on to the old wooden post and searched around there as well, with the same result.
Perhaps the race lies slightly further to the left or right and I simply missed it. Who knows? In the locations where I have already found access points to the water race, they have generally been positioned against the bench cut of the old track, so that was where I concentrated my search.
From there I pushed further east and came across a depression beneath a tree on the steep hillside. It looked interesting enough to investigate, so I removed a few rocks and stones, but soon hit dirt and clay. That would require proper digging.
It is difficult to know whether the site is a genuine candidate. The sections of the water race I have found elsewhere tend to be buried beneath rocks that have gradually moved down the steep hillside over the decades. When I hit solid dirt or clay, I usually begin to suspect I am looking in the wrong place.
I marked the spot for another visit and moved on.
Next I headed towards an area where, on an earlier trip, I had discovered a large metal ring. I managed to relocate it and also found an old metal pole nearby. The ring itself was surprisingly heavy when I lifted it. What either object was originally used for remains another small mystery.
I then dropped down to the road below the hillside and continued along it. Near the security gate I followed what appears to be an old track running above the road. The route was heavily overgrown, but despite cutting across a steep hillside it remained remarkably flat. I followed it as it gradually gained height before beginning to descend again. Rather than dropping with it, I decided to bush bash straight up the hillside.
That brought me out between the old wooden post and the mysterious trench. From there I continued climbing until I reached Maintenance Track, an old section of track or road running above the Orongorongo Pipeline.
I headed west along Maintenance Track, crossed the earth bridge and photographed the water trapped behind it. I continued towards the Old O-K Venturi Meter Hut, but before reaching it I turned uphill towards an area where I believe another section of the water race track survives.
However, instead of following that route behind the old hut, I decided to keep climbing straight up the hillside until I reached the ridgeline.
Along the top is an old fence marking the boundary with private property extending from Moores Valley. Beside the fence is an old track, now partly swallowed by gorse and young mānuka. I had encountered it on an earlier bush bash, but had never followed it for any great distance.
The old firebreak can be seen in this 1954 aerial photo
This time I headed west along it.
As I walked, it gradually dawned on me what I might be following. The route lined up remarkably well with an old firebreak visible on aerial photographs from the early 1950s, around seventy years ago.
At times the track disappeared into thick gorse and I had to detour around the worst sections. Every so often the vegetation opened just enough to give me partial views down across the regional park, the recreation area, Hine Road and Sunny Grove.
Eventually, I reached the end of the ridge, where the ground dropped away steeply. There appeared to be an old route descending the hillside, although it did not seem to be part of the original firebreak. Judging by my position, I calculated that if I followed it downhill, I should emerge somewhere near the shaft of Coleman’s Tunnel.
This raised an intriguing question: why would there have been a track leading down from the old firebreak towards the tunnel shaft? Could it have been an access route used during the construction of Coleman’s Tunnel in the early 1880s?
The area around the shaft also appears to be one of the widest sections of the Water Race Track, suggesting it may once have served as a working area where tools, equipment and construction materials were stored or handled while the tunnel was being built.
That calculation proved correct.
As soon as I reached the water race track, I could see part of the race itself where soil had been removed to expose it. From there it was only a hop, skip and a jump to the tunnel shaft.
At the front of the shaft is an opening that acted as an overflow outlet whenever too much water entered the system. During the 1880s and 1890s, overflow water poured through here and travelled down a chute carved into the rocky bank below.
I had looked at the chute before, but this time I decided to follow it all the way down and see where the water would actually have gone.
That turned out to be more adventurous than expected.
The chute is extremely steep in places and I had to use branches and vegetation to steady myself as I descended. At one point a handhold suddenly gave way. A small avalanche of fine, dry soil slid into the chute and straight down the neck of my T-shirt. Because I was almost vertical at the time, I could feel the dirt running down my back and stomach.
There was only one solution. Off came the shirt momentarily so I could shake it all out.
Eventually the chute reached the remains of the Orongorongo Maintenance Track, now extremely overgrown.
That raised another question.
If overflow water came down the chute, did it simply continue downhill towards Reservoir Road below? That seemed an odd arrangement, because a large volume of water running directly towards the road could easily have caused serious erosion.
Once I emerged onto Reservoir Road, another possible clue appeared. Alongside the road is a trench that leads towards a pipe running beneath it. From there, a cut water channel carries water into what is now Richard Prouse Park.
This could, of course, be a more recent feature, but I am inclined to think it may be older. Modern drainage would more commonly use pipes or formed culverts rather than a relatively crude channel cut directly into the ground.
In the 1880s, the area below the road looked very different. Old photographs suggest it was largely regenerating scrub and low vegetation rather than the developed parkland we see today.
There is also an old photograph from the 1880s showing Coleman’s Tunnel, with the shaft visible above it. I have tried to trace what I believe may have been the route of the overflow, and I think part of it can be seen in the photograph. What happened to the water after it left the chute, however, remains a mystery.
The same photograph, to the right, also appears to show a former channel of the Wainuiomata River running between Top Pool and Secret Pool. I photographed this old stream of the Wainuiomata River during this exploration, and that image is in the gallery below.
I eventually headed back to the car. I had not solved the mystery of the missing section of water race, nor had I conclusively identified all of the old overflow route from Coleman’s Tunnel.
But that is often how these explorations go.
So while I came home with relatively little solved, I did gain several new clues and got a decent workout in the process.
I call that a win.
