The current effort on NZ Rail Maps to map the Otago Central Line started in November of 2017 - about 18 months ago. It was at that time with the first of the posts in series 47 that we started the widespread use of the LINZ background imagery and bringing in historical imagery with the mosaic projects. We had at that time hoped to complete the set of maps for the entire line by a series of deadlines which eventually stretched out to the end of 2018.
Since the beginning of this year we decided to temporarily set the Otago Central line aside and work on other projects. One of the reasons for this is that LGGA are still scanning the aerial images for that area and adding new stuff all the time. Rather than doing an area then finding there is new stuff and going back to add it is a good enough reason for deferring the completion of work on maps for railways in Otago.
We just recently discovered LGGA have found survey 1452 which is State Highway 8 that we have used for the Cromwell Gorge has been added so we are currently poring over that to see if their scans are better quality than what we already have. Another example is patiently waiting until finally the one and only good quality scan of Ida Valley became available which was late last year.
We don't quite know when Otago Central will be completed but it is still very much under consideration and being worked on behind the scenes from time to time.