Wednesday, 2 January 2013

On the Otago Central trail [1]

Yesterday I started work on the map of the Otago Central Railway and it is progressing well. The OCR is a line we know a lot about because of the research done and books that were published, notably Dangerfield & Emerson, and also because the Department of Conservation has done archaelogical surveys of the bulk of the route which remains in the Rail Trail. Thus the map document will include a full list of stations, and most of the bridges beyond Middlemarch, as well as ballast pits etc. Of course with the benefit of GE or Bing Maps coverage we can also determine fairly accurately where some of these places were as well. There is some of the area that still has only medium GE coverage but those areas are also covered by Bing Maps at a higher resolution. The DOC bridge list includes grid references to the obsolete NZMS260 series maps rather than latitude/longitude coordinates. LINZ have coordinate convertors on their website to turn these grid references into WGS84 latitude/longitudes. So then I was able to check these coordinates in GE. It is good to see that Google has gone back to having visible points when editing paths in the latest edition of GE.
The table list of this data has now been completed and can be seen in the documents uploaded to the website. The maps are being drawn up and this posting will include some points of interest found so far with the maps.
Firstly, Wingatui. We know that the layout was different before the main line from Dunedin was duplicated and upgraded. One part of these works was to build a new double tracked tunnel to the west of the old single tracked tunnel (which is still there incidentally). In part because of this but also for more convenient operation, Wingatui station was moved to be closer to Dunedin.
On the old single track route, Wingatui was further west as shown, and originally trains which stopped at Wingatui used to have to reverse to go up the Central with the triangle leg shown. Later on, according to Dangerfield & Emerson, there was a backshunt put alongside the main line closer to the racecourse, and trains for Central would set back from the Wingatui station before going up the leg that faces Dunedin. The duplication works completed in 1914 changed all that by moving Wingatui to the east. Then both tracks would be able to connect to the facing leg (the leg going the other way was apparently lifted with the change in layout). Now the mainline has been singled again, things are a little simplified in the yard. The little dot over Paterson Road is where the overbridge is – I haven’t yet drawn that in. The zero peg for the Taieri Branch is just west of that bridge.
Firstly, at Taieri / Wingatui we have the Taieri Industrial Estate sidings to the left, and on the right we can see a proposed route for the Taieri Ballast Siding. There is not enough documentation about the latter nor any ground evidence today to confirm its route, although we do know where it joined the main line (3.2 km) and where the pit was that it went to. The Taieri Industrial sidings are what was shown in the LDS data layers. These are the siding for Fisher and Paykel to the right, a timber plant at the bottom (I think) and the Silver Fern Farms (ex Fortex) meat processing plant to the left. The layout has been changed quite a lot since the F&P plant was taken over by Fonterra and the current layout is shown below. It also shows a loop on the SFF (now Polarcold Coolstores) siding, which I think has always been there.
As you can see, the Taieri Estate sidings now start with a headshunt just to the north of Silverstream Bridge, and the sidings all go off this. The original siding is the lower curved one and has been extended with an extra loop. The backshunt that used to be used by F&P (it never went inside any building, even though the building layout has been changed by Fonterra) is gone. The biggest change to the site is the two new sidings added at the north side, the backshunt of which goes right up to the boundary with Polarcold.  (Note the above map is a bigger scale than the previous one).
The Taieri Industrial Branch ends just a bit further north at 3.5 km and the Taieri Gorge Railway starts there. At the location they call North Taieri, the TGRL have built a crossing loop for their trains. I presume crossing a train there is cheaper than doing a crossing on Kiwirail’s tracks. The last time I went to Middlemarch on the TGRL which was 3 1/2 years ago, we crossed a train there because it was a busy day with two trains running. So as our train came off the TGRL, we crossed the train going to Pukerangi that day.
ntaieri S5_20090412_263
On the left you can see what North Taieri looks like on the map. On the right is the crossing of our train. Because of the wagons that had been left in the loop, the Pukerangi train had to back out of the loop back on to the main line after our train had passed. North Taieri is roughly at 4.0 km, which puts it a little to the south of the location of North Taieri Tanks, a set of water tanks that were used to top up steam locomotives in the earlier times of the line (closed 1936). The original length of the Taieri Industrial Branch was to have been 4.0 km but the end was moved back to 3.5 km because it was too close to the level crossing, apparently it would have made Kiwirail responsible for the crossing in some measure.
At the moment there is a lot more I could do in terms of looking at where things are or used to be on the OCR. I’m not going to look at everything just now, but definitely will come back to some things at a later date, like where some of the other ballast sidings went – I just picked up the Taieri one from my old Google Earth stuff.