NZRM Progress Report 2023-11-25: Volume 6

Work on maps recently has been focused on Volume 6. In the 1960s the NIMT between Porirua and Plimmerton was doubled, electrified and realigned. Whilst mapping has been done on this section before, it needed to be redone to make it easier to overlap the mosaics produced from Wellington to Porirua which are in a different mosaic project. This has been done, at the same time adding additional generations of aerial photography of Porirua Station and particularly some older ones dating back to 1941, or 1944 with enough scale to pick out some of the features of the original station. This is useful as previously it was very difficult to have a clear appreciation of what Porirua looked like before the line through there was doubled and the station replaced. Most of the aerial coverage that is of good quality is from 1959 and later, when the doubling project was in full swing. Once all the maps of Porirua have been completed, the generations covered for the station and yard will be 1941, 1944, 1959, 1961, 1969, 1972, 1977, 1982, 1986-88 (the exact year in that range TBD), 1995 and several years between 2000 and the present day (TBD at this time). The station got extended passenger facilities but the freight handling capability was also upgraded. There is no longer any freight loaded at Porirua at the present day.

The Project is about to request some bulk surveys from the Crown Aerial Film Archive for Volume 6. These are mainly for railway corridors – the NIMT, Wairarapa Line and Palmerston North Gisborne Line – that fall within Volume 6. Some aerial coverage of parts of the Foxton Branch using different surveys will also be requested. A Project computer is being upgraded to have 3 TB of disk storage to keep the bulk surveys on whilst they are sorted for use. The initial request is around 500 GB, but arrangements will be made to have future, annual transfers of 2 TB each for the life of the project (seven years) unless Linz introduces a website that enables individual photos or runs to be downloaded on demand (just as is currently done with the Koordinates website for the other aerial photo collections they hold). The latter is certainly what the Project hopes to see in future.

Work is also continuing in preparation for this year’s annual update of the webmaps site. Some stations have been identified as missing from some of the corridors captured in earlier updates and have been added to the maps. In summary, there are some technical gaps in the capture coverage being identified and corrected before another capture is completed. As due to the difficulty in migrating to vector tiles, investigated earlier in the year, means it will not be possible to resolve various technical limitations of the webmaps site, the flaws and challenges inherent to this platform will not be able to be resolved for the present time. The main improvement at webmaps will be the content that has been upgraded and added since the preceding update.