Thursday 11 October 2018

Otago Central Railway [64A]: Middlemarch-Ranfurly 1 / OCR Maps From Here

This isn't a new series as such but it is about adding to the work already done in this sector of mapping the OCR. Yesterday I had a look for new Retrolens aerial photo content for the stations in the Ida Valley area and have obtained a significant amount from recent RL additions. I then decided to have a look for content further down the line as I did not have any good aerials of a number of locations. This was summed up in detail in this post I did last December. It basically has said that coverage not yet available at that time could include the following areas (updated to those areas I haven't yet mapped or finished):
  • Auripo
    • Survey 112 of 1939 which is now available. The only higher res coverage for when it was open.
  • Ida Valley
    • Survey 112 of 1939 now available. Again the only higher res coverage for when it was open.
  • Ranfurly
    • Survey 890 (1956), 1745 (1965) and 5800 (1980) should cover well. 890 in particular is important as it gives the best early coverage which probably will show the old locomotive depot and turntable at the north end. As far as I can tell none of these are available yet. Survey 112 goes close to Ranfurly but not actually over it.
    • Survey 2590 is available. This looks like it is an official NZR survey as it only covers the railway yard. Taken in 1973 it will let me publish full aerial maps of Ranfurly.
  • Waipiata
    • Survey 2833 is the only really good coverage of Waipiata. Again it appears to be the official NZR survey that was taken in 1975. This is good as there is really nothing else suitable for Waipiata. NZR must have had reasonable confidence these two stations would be staying open to have these surveys done as there are not these surveys in existence for every station.
  • Hyde
    • The ballast pit when the siding was opened is not covered in anything I can find. I have found lower res images from 1959 and 1960 (Surveys 1053 and 1214) which were 7-8 years after the siding was removed. It does give a clue as to what the pit looked like in that era (it was kept open without a siding because NZR used trucks to bring ballast to the Hyde yard to be loaded there). So it should be possible with that to estimate where the siding ran, which will be marked as "uncertain route". I do have some data for the siding that should help with the route, but not an actual map. 
  • Pukerangi-Taioma
    • There is some 1940s coverage now available which should be reasonably sharp but is actually not too good (I don't know whether it was a bright day or if the scanner overexposed the scans as they are a bit washed out). I will see if that coverage is useful.
    • In many cases I have now obtained station diagrams from Archives Dunedin.
  • Wingatui-Taioma
    • I have some Dunedin City aerial photos and a bit of Retrolens stuff. I am unclear how useful that stuff is.
    • I have also obtained station diagrams.
So there we have it. The original post linked above also had diagrams taken from the aerial footprints layer to show coverage through the decades. It is interesting to view those diagrams in relation to the map of the line. 

At the moment I am updating the maps of the Ida Valley stations (Auripo, Ida Valley and Oturehua) through the new coverage that has just been obtained. Here is a description of the remaining sections to be mapped:
  • From the Ida Valley the route goes through the gap between Rough Ridge and the Idaburn Hills down into the White Sow Valley, and then through another gap at the north end of Little Rough Ridge to Wedderburn. Essentially we call this the "Wedderburn Summit" or "Wedderburn Pass".
  • From Wedderburn down to Ranfurly and Waipiata is in the Maniototo Plain and railway-east of Waipiata the railway follows the narrow valley in the upper reaches of the Taieri River closely until Hyde and then the Strath Taieri through to Middlemarch. 
  • Railway-east of Middlemarch the line gradually closes in on the Taieri River valley, finally entering the gorge east of Pukerangi and eventually exiting at Taioma, descending through the hills until it enters the Taieri Plain at Wairongoa. 
  • The last few kilometres is across the relatively flat Taieri Plain to Wingatui.
The names of the stations, with the probability of maps (High, Low or Nil), are:
  • Auripo - H
  • Ida Valley - H
  • Oturehua - H
  • Wedderburn - H
  • Ranfurly - H
  • Waipiata - H
  • Taieri Lake Siding - N
  • Kokonga - H
  • Tiroiti - H
  • Hyde / Hyde Township / Hyde Ballast Pit - H/H/H
  • Rock and Pillar - H
  • Ngapuna - H
  • Middlemarch - H
  • Sutton - H
  • Matarae / Matarae Siding - L/L
  • Pukerangi - H
  • The Reefs / Quartz Reef Siding - L/L
  • Flat Stream - L
  • Deep Stream - L
  • Hindon - H
  • Christmas Creek - L
  • Mt Allan / Little Mt Allan - H/L
  • Parera - H
  • Taioma - L
  • Salisbury - H
  • Wairongoa - L
  • North Taieri / Tanks - H/L
  • Taieri Aerodrome / Estate - H
  • Wingatui - H
These probability scores reflect the availability of suitable aerial coverage or diagrams. For something that has an L score, you will most likely only see the station site marked but not any other detail. In some cases there was nothing at a specific location, it was just a stop on the main line with no infrastructure. In other cases I can't get a diagram or aerial photo. So North Taieri Tanks is just going be marked because there was never a siding, Machine Creek which isn't in the above list and the water tanks at Prices Creek, Mt Allan water tanks, Little Mt Allan halt with no siding or shed and the like will just be marked as a point on the line. 

As far as miscellaneous sidings go like ballast sidings that are on the chainage charts, the points and direction will be marked (and the length if known) but not the actual route because that often isn't clear. Ida Valley pit doesn't have a siding marked but the water tanks and coaling facility are marked. There are a lot of little details like that that will be marked wherever possible but not with much clarity because that's just the way it is.

There is still a lot of work to do with the maps and I expect this to continue into next year and it is hard to say how long it will all take but I can't see it taking more than 12 months but I am not really sure how long is needed.

The subsequent posts to this one will finish the 63 Ranfurly-Alexandra series so it will be a while before you see [64B] and subsequent posts in the 64 series for Middlemarch-Ranfurly.