Palmerston North Gisborne Line [0O]: Volume 5 Progress Update 15

We are pushing on with all possible speed to complete this volume of maps, but some late changes have meant that the maps for the Makaraka Branch have had to be redrawn for the second time this week. This means the series of maps for this line have been generated three times in total over a period of two weeks.

This is happening as we get into the intensive work of checking and updating everything, and finding in this case and in other cases that more historical aerial photography needs to be put into the GIS, and also in the case of the Gisborne region, discovering that the higher resolution 0.125 metre Linz imagery dated 2012 can be substituted with 0.3 metre imagery dated 2017 if we need more up to date base coverage in some areas where 2012 is too far back and where the scale of a map is not large enough for the resolution difference to be material. An example of this is at Makaraka where the old Apple and Pear coolstore lately occupied by Weatherell Transport burned down in 2016 and was subsequently demolished.
The first revision of the Makaraka Branch coverage done two days ago was completed after creating the first lot of historical tiles for various stations on the branch and resulted in the total number of maps and diagrams for the Moutohora Branch being increased to 115, which included an increase of the number of diagram maps from 40 to 47 and an unknown increase in the number of aerial maps to 68. This meant that the sequence numbers of all the diagram and aerial maps above a certain level were incremented by 7 using a special script we have available. For the latest revision we maintained the existing sequences by revising the coverage of the diagrams within the first 10 sequences so that we were able to squeeze in an extra higher resolution diagram of Park Racecourse station whilst keeping practically the same amount of detail of Makaraka station despite reducing the scale of several of the diagrams there slightly. There are now 47 diagram maps and 65 aerial maps, which is a small reduction in the number of aerials but with practically no loss of detail, the reason being that we had covered all of Makaraka yard at a ridiculously large scale of 1:500 and reducing this to 1:1000 for most of the yard except for the middle section containing the key infrastructure has not materially impacted on the presentation of the information for this area.
The revised diagrams have not yet been uploaded. This will be performed over the next day or two and announced in the next progress update.
Whilst we will continue to post these progress update reports as the work of completing Volume 5 at Basic level continues, we will no longer be posting significant map content in them. Instead, it is time to revert to posting specifically titled articles about particular sections of the maps such as station yards. To this end we pulled the content for Makaraka Branch out of the last progress update and it is being published in its own right in the first part of a three part article covering Makaraka, Matawhero and Muriwai. This article needed the full revisions of the Makaraka Branch to be completed before it could be produced so we expect this post to appear on the blog tomorrow. This also means the content itself is significantly updated from what was formerly in the previous progress update.
The next stage is to complete the maps of Matawhero Station. We discovered that 1951 aerial coverage of this station was significantly easier to work off than that from 1966 so we added the former to the mosaics, which has necessarily slowed down work a bit, but the maps are now almost complete and reveal this yard was once much bigger than it is today and even had a full bridge at the south end. We also added a 1951 aerial of Park Racecourse to the mosaics for the Makaraka Branch which has also slowed down the revision of the maps for that section. Some additional sidings at Gisborne either side of Stanley Road crossing have been added to the maps for Gisborne Station with the 1986 NZR corridor survey providing the necessary source for tracing. Then Muriwai is the next yard to be completed and that should allow us to finally finish the main PNGL corridor.
After that, to complete Volume 5, we still need to finish some of the yards further down like Dannevirke and Waipukurau, Napier Port, Ngatapa Branch, Gisborne-Opotiki Survey and… maybe that’s all of it or maybe there is something else we missed? So there is still quite a bit of detail work. Because it now seems unlikely we can finish all this by the end of this week, we have pushed the deadline out yet again, but we really have to pull all the stops out to have this volume finished by the end of January at the very latest, i.e. by the end of next week. So the pace continues unabated.

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