Tuesday, 21 February 2017

Otago Central Railway [9]: Wedderburn-Auripo

Here's some features of the line between Wedderburn and Auripo. I have rushed ahead with marking mileposts up to 102 M and features and have yet to draw layouts of Oturehua, Ida Valley and Auripo stations.

Bridge 65 (Wedderburn) and Bridge 66 (highway overbridge). There have been two bridges at the latter site. The present bridge dates from 1966 (according to the DOC notes).

In an earlier post I wrote at length about the highway realignment between the 88 and 90 milepegs. The old highway route had a level crossing of the railway just before it reached the route summit of 618 metres above sea level. The railway then crossed the 45th parallel for the first time.

At some time before the highway realignment took place, a second overbridge, No.66a, was added near the 89 mile peg. The date being uncertain. I previously stated this could have been 1950 but now I have the chainage charts I see the entry recorded for this date simply states the clearance under the bridge. Additional research would be needed to clarify the installation date. I also have no idea when the highway was realigned but I am guessing it could have been in the late 1950s or early 1960s. Prior to installing the overbridge the highway crossed on the level just north of the bridge site.

Bridge 66a as seen from track level and road level respectively. The first photo is by Gerald Hyland. As was common in an earlier era, the bridge was placed at a right angle to the tracks in order to make it as short as possible, creating an S bend in the road.

At 92 miles just north of Oturehua a ballast siding was located with an engine shed for a time.

This ballast siding between Oturehua and Ida Valley at 95 miles has been marked previously on maps by me.

At 102 miles this is believed to be one of four alignment changes on the line. The others being at Wingatui (junction curve), Prices Creek (bridge replacement), and Clyde (new station site). Dangerfield and Emerson mentions an unstable hillside near Auripo (101 M) where a small deviation was later required. When I travelled on the line in 1989 a subsidence at this point dating from the 1950s was mentioned in the commentary given by George Emerson. The chainage charts show at this location only a continuous right hand curve, not the R-L-R curvature of the later route. It would appear the hillside subsided at this point and the bypass track built to get around the collapsed embankment became the permanent route.

Monday, 6 February 2017

Otago Central Railway [8]: Waipiata-Ranfurly

Whilst progress has slowed a lot lately I am still working on the maps as time allows. I have discovered that aerial photography at 0.4 metres resolution is available for the entire line (there is higher resolution coverage available for a few areas close to Dunedin as well). This is very material to what I am doing because Google's licensing forbids copying from their imagery, meaning I have to change all the maps to use only Linz aerial photography as their source. It is likely I will have to download aerial photography for every map in NZ to ensure that all content has been sourced from the Linz coverage rather than any other source that may have licensing restrictions applying to it.

Waipiata station (approximate layout). This overlay uses 0.75 m aerial photography that I downloaded before I became aware of the 0.4 metre Central Otago coverage. I will download this higher resolution photography over the next few days and load it on Qgis so I can make sure I don't need to use Google Earth at all.

Ballast pit (red x's) between the 75 and 76 mile pegs, just south of Ranfurly. The map below illustrates this location.

The locomotive depot area immediately south of Ranfurly. The map above shows the location of the turntable and engine shed, while the image below is from Whites Aviation and shows the development of these facilities in 1951. Prior to that time Ranfurly had an engine depot north of the station.

Wednesday, 1 February 2017

Otago Central Railway [7]: Kokonga

So today we are having a look at Kokonga, Here's a few maps.

In the last two posts I showed where the station building was relocated to after NZR sold it, and what it looks like today. I don't know when that happened, but probably sometime after 1985 when the station was fully closed.

Here is the overall layout of the station.

The ballast siding went right towards the river, crossing over the main highway, and the embankment downgrade to the crossing remains clear today. The area directly behind the station building was set out as a township, and you can still see the section boundaries on that map, but there is nothing left of that settlement today. There is an old church and some possibly period houses alongside the highway to the north of the ballast siding, and a couple of other houses nearer the station, but of course the relevance of them to the railway isn't clear to me.

Here we have a closer look at some of the detail of the main station buildings.

At the north end of the station yard were the ballast siding, engine shed siding, the water tank and a house. Dangerfield and Emerson describe the water tank as being gravity fed, and while they don't elaborate on how this worked exactly, the railway line is on a ledge between some hills and the river, so it's quite possible a water supply was tapped on a hillside to the west of the station to supply the tank. The engine shed probably dates from the construction days and would have been removed when the railhead moved further westerly.