Thursday, 12 September 2019

Project Diary 2019-09-12: Hornby Industrial Line

As we continue assembling maps for Christchurch Transport Blog use, currently we have shifted to the Hornby Industrial Line, which is historically the section of the former Southbridge Branch from Hornby to Lincoln. It was designated as such in July 1962 after the branch was closed beyond Lincoln. In December 1967, the section of the Hornby Industrial Line between Prebbleton and Lincoln was closed. Subsequently, the section from around 3 km to Prebbleton was closed, although most of the track is still in place as far as Springs Road, except for the section now crossed by the Christchurch Southern Motorway, SH76. The Prebbleton overbridge was demolished in 1997, and all of the corridor south of Springs Road has been built over. The section from south of SH76 to Springs Road has been reused for a rail trail alongside the mothballed track. 

From time to time the idea is floated that the line could be reopened to Lincoln and if this were to take place, the route beyond Prebbleton would have to be changed due to the reuse of the corridor, including new station sites.

The maps below show some of the sidings which can be traced in the 2015 aerial photography. We know that many more will be visible on the historical map mosaic tiles when they are finished.

Around 1 km, with a siding visible across the site of a demolished building.
Around  1.5 km, at least three sidings are still partly in place.
Quite a notable siding around 2 km.  These premises are currently occupied by Pengelly Transport and may possibly have been used by Toll Freight at one stage.
The lengthy Watties-Tegel siding at around 2.5 km. This was the last siding used on the line. With the closing of this siding, there is no traffic currently moving on the line.
United Empire Box Co Ltd (known today as UEB) seen above in 1973 with a siding. There is no obvious trace on the aerial photos of this siding today.
UEB in 2015.
Prebbleton yard seen in 2012.

Saturday, 7 September 2019

Project Diary 2019-09-07

As some will know, this week CHAT Club released their "MaRTI proposal", which suggests the Middleton rail yards could be turned into a housing development. A couple of posts about it have appeared on Christchurch Transport Blog, but the indepth analysis hasn't been done until the historical maps of Middleton are ready. As per usual this has taken longer than expected but right now they are about to be saved in their final form.

The Gimp project covering this part of the MSL takes in from Middleton to Sockburn in order to keep the project at a reasonable size but it still has nearly 80 layers and a file size of just over 30 GiB. As per usual we start with 1940 as the first era covered, then 1950 and 1961. These three eras in particular are pretty much what can be found to cover any part of the railway landscape in Christchurch, but they are not rail specific. They vary up to about 1:16,700 scale. What is rail specific for this particular part of the MSL rail corridor are the NZR station surveys, which are in particular for Middleton in 1967, Hornby in 1972, Middleton again in 1975 and Sockburn in 1980. The actual areas covered extend outside those named stations. Typically the station surveys have a scale of around 1:4300.

Then we have the MSL corridor survey starting at Lyttelton and heading to Ashburton in this case, and it dates from 1984. Scale for these corridor surveys is usually 1:5500. To finish off we have two more non-rail surveys which are again standardised over much of Christchurch, and they are from 1994, and the only colour one which is from 2000. These last two are at a scale of 1:50,000 and because they cover such a large area at that scale, they have to be trimmed down to covering only the base tiles that we actually use in order to avoid a lot of unnecessary pixels having to be saved in the file and blowing it up too big. To explain further, these are the only layers that cover the whole area of the project canvas in one single layer, and with a canvas that is only half filled, due to the shape of the base not being a nice and regular, we have to avoid covering areas of the canvas that aren't occupied by the base layers, because it just wastes file space unnecessarily and it can add up to a few extra GiB each time we save, which is a big deal.

Tuesday, 3 September 2019

Project Diary 2019-09-03

Chat Club, a group of transport professionals that has been running rail passenger workshops in Christchurch, proposed at a seminar on Monday evening that the Middleton rail yards could be closed down and relocated further west, to enable the land occupied to be redeveloped for medium density affordable housing (1600 homes approximately). About 50 people attended the presentation, including a number of candidates in the upcoming local elections.

There have been two articles in the "Press" so far:
The first one is the details of the proposal and the second one states that Kiwirail is not planning to move from the Middleton site.


At this stage it will be interesting to see where the proposals go as it will now have to be looked into further as an option if the Minister of Transport decides to investigate the idea. At the same time there are several other possible sites nearby, such as Addington Saleyards, Waltham freight yards and Linwood Loco Depot land which has either been undeveloped or minimally developed.

As for NZ Rail Maps we have historical maps of Middleton currently in the works and these will probably be posted on this site later this week or early next week. We also will have the historical maps of Linwood and Waltham available soon as well.

Sunday, 1 September 2019

Project Diary 2019-09-01: Comment on our relationship with the rest of the NZ rail heritage community

As many of you know, we have not always enjoyed good productive relationships with the rest of the NZ rail community which is partly why this project has its own separate Facebook presence and our involvement of various hobbyist groups has waxed and waned over the years. Ongoing politics relating to this project and to Patrick personally has continued to the present day.

Because of this the decision was made the decision over the last week to withdraw from every Facebook rail-specific group and the implementation of this was completed as of today. A project-related membership is still held of one or two minor and specialist groups that are not read or visited very often which are exclusively related to map production and sharing.

It may be we will review the group membership and rejoin in the future but at the present time we just need a break from these forums which has been a difficult and ongoing issue over the past decade or more.

There are a few people in the Project's own Facebook group who have provided us with or may be able to continue providing us with valuable resources in the future and we would certainly like to thank each and every one of you who has assisted with this and is able to keep assisting with this into the future.

This decision does not in any way affect the continuation of the project in the slightest. It is simply a reflection that a break is needed from these groups which are currently contributing very little to the overall project and we need time to evaluate the contribution they are making to the project and whether it has been worthwhile. We have left those groups on good terms with the admins and could easily choose to rejoin any of the major ones at any future time.

The project will continue the same tomorrow as it did yesterday or last week or the month before and all of its resources including our own Facebook group, Blogger blog, the Wordpress website, and Google Photos albums of all the information will carry on exactly as they do now.

The decision reached is to allow us to concentrate on this project more exclusively and to facilitate stronger relationships with other related projects that are Canterbury based. This includes membership of local and national railway preservation societies and contributions made to them, and the development of rail campaigning that is being facilitated through Christchurch Transport Blog. Membership is retained of a small number of groups related specifically to the campaign interest. It has been found that the personal relationships being fostered through these developments in groups with relatively smaller membership have become far more valuable than much of the associations and acquaintances that have occurred through the broad based rail community Facebook forums and the interaction with their large membership.

We believe the future of this project and of our work in Canterbury and to some extent nationally in promoting rail and rail heritage looks bright for the coming weeks and months and we welcome and acknowledge all the ongoing support of each and every person who has supported this project since it began in its current form at the start of 2008. Currently the project is working to an assumption that over the next two or three years there will be a concerted and conclusive effort to bring as much of the project as possible to a completed state so that the activity level on it can be wound down. This has been alluded to in posts at earlier times referring to development schedules. As this year's original development schedule has not been met, due to other projects becoming more prominent, it will be reviewed at the end of this year and revised accordingly to make sure it is still possible to achieve the original goal. We anticipate it will not be possible to continue the current scale of map production of the last three years in particular although there is no timeframe for when the current level of resourcing is expected to decrease, and as referred to in the last one or two posts, resourcing has been increased this week to enable the mosaics in particular to be produced more rapidly because that is the part of the project that takes the most time to complete.  The additional resources cost a mere $62 to provide and consist of a larger SSD for a computer and have had a significant impact and will enable us to much more efficiently utilise project time which is very important as there are now the competing demands that will continue.

To conclude and summarise the project leadership does not believe that this decision will have any major impact on the project, the project schedule will not be changed from where it was yesterday or in the last week or month, the project welcomes and continues to welcome the contribution of all the members of our Facebook forum and other associated means of contribution, and the project continues to forsee a bright future for the continuation of the project in the coming weeks and months. Thankyou to all personally for your support.

Saturday, 31 August 2019

Project Diary 2019-08-31

In today's update, we can report we have finally completed the historical map mosaics for the section of the Main South Line from Woolston to Waltham, after splitting the Gimp project into two parts to deal with persistent crashes caused by project file size. The last section to be added this morning was the historical coverage of the section for the year 2000, which is the most recent aerial photography available from Retrolens.

The historical eras covered in these mosaics of the Main South line are 1940s, 1950s, 1960s, 1970s, 1980s, 1990s and 2000s, with Linz aerial photography available after 2000. NZR official station surveys cover from Opawa to Waltham in 1970, Woolston in 1974, and Woolston to Waltham in 1981. NZR corridor survey is available from 1984, but only for Waltham; for some reason, an entire run (B) is missing from this survey. The rest of the coverage is general for Christchurch and of a lower quality and only the NZR surveys in general will be able to fill in the historical data for the section.

To back up the map data, this week we also have commenced three half-days of research at Christchurch Archives at the rate of one half-day per week for the Christchurch Station, which includes Waltham. We are prepared to carry out the more intensive scale of research just for Christchurch, and do not intend to spend any significant amount of time on the other stations, each of which would have less than one half-day spent on them. In each half-day session we would typically expect to view and copy content from around 40 files, and the time scale of one half-day per week is governed by limits on the rate at which Archives can produce and issue the files for our research. The main purpose of this research is to obtain additional map information about the locations and track layouts of sidings and time limitations mean we are not able to take in general historical research of the areas concerned, even though much of the information about Christchurch in the 1980s and 1990s is very interesting, being an era we lived through and had extensive knowledge of from a personal perspective.

At the moment our focus is going more into producing all of the mosaics as quickly as possible for Greater Christchurch, and less into drawing actual maps, and that is why we are publishing project diary updates lately rather than map coverage of the areas. This is driven by the needs of Christchurch Transport Blog for map tiles for project work, being a higher priority than NZ Rail Maps at present. Once all of the Greater Christchurch map tiles have been completed, then NZ Rail Maps can go back into map development around the country according to its existing goals. This of course also means the original project schedule for NZ Rail Maps that we outlined for 2019 will not be kept. We estimate at the moment it may take for the rest of 2019 to be able to complete the Christchurch Transport Blog map tiles, and therefore will have to rearrange our goals. 

This will mean the overall schedule for completing the bulk of the NZ Rail Maps project work for all of New Zealand will be altered. Against that, having increased resources has improved our efficiency considerably this week and will speed up the mosaic production.

Tile extraction for Woolston to Waltham will start early next week, so expect to see some actual historical mappables displayed in the next update. Mosaic production is shifting to the Middleton to Hornby section of the Main South Line, the Lyttelton to Heathcote section of the Main South Line (including Ferrymead) and the Bryndwr to Ashley section of the Main North Line which as far as possible will be worked on more or less simultaneously, as is now easier to achieve with the resourcing improvements.

Thursday, 29 August 2019

Project Diary 2019-08-29

This week work is still continuing on the historical map tiles for Waltham, Linwood, Opawa and Woolston. We have gained some additional resources this week to enable us to speed up the tile production work, so we are also simultaneously working on tile production for Middleton to Hornby section of the Main South Line, and the Bryndwr to Ashley section of the Main North Line. So the production of these tiles should be able to be sped up noticeably, as part of the reason for it being slow is the inherent slowness Gimp has when working with very large mosaic projects. Some of these cover a canvas surface having a working area of 3.5 billion pixels (3,500,000,000) and around 100 layers in total. The Woolston-Waltham project is now completed and tile extraction will be commencing and could be completed tomorrow but will probably have to be deferred for a couple of days due to other commitments, and we have had numerous Gimp crashes, so it has been slowed down a lot from what we expected last week.

The issue with a city like Christchurch or any main centre is you are looking at an entire section of a corridor, rather than a number of individual stations along it. Because there are sidings and stuff all the way along that corridor that you want to document, and that is certainly the case for the Main South Line from Woolston to Islington in particular, and on the Hornby Industrial Line as far as Prebbleton. It is not quite the same on the Main North Line which has historically much less industrial development. So that dictates Gimp projects that cover large areas. We could split these into multiple smaller projects but then there is too much problems with overlapping at the edges of these projects because those edges all have to line up when the tiles are put together in Qgis, and the historical aerial photos boundaries don't neatly end on a tile boundary. So a smaller number of larger projects is definitely the way to go, but we have had a few instances of having to split some of them up when they got too large. For example Addington to Ashley started off as one project, but then Addington and Riccarton got combined into another project with Christchurch and it ended up too large to put the rest of the MNL suburban area into it, so Bryndwr to Ashley is what it has ended up as. Same with Lyttelton to Waltham originally being one project that now has Lyttelton and Heathcote in one file and Woolston to Waltham in another. And so on. 

The extra resources mean the time Gimp wastes on saving large projects, which can actually take several hours to complete, can be used to work on another project at the same time. So in fact today we really were working on three at the same time at one stage because the first one was being saved. After completing the progress on the second one, it too was saved, and while that was happening, we worked on the third. Another time saving measure is to use Cubic interpolation for unified transforms instead of LoHalo. My hunch is that Cubic is a lot faster than LoHalo and makes very little difference to the quality of practically any layer we throw at it.

Thursday, 22 August 2019

Project Diary 2019-08-22

Since last week's diary report we have continued working on the maps for the Christchurch area. Putting together all the aerial photos can take a while to complete but we now have complete historical aerial photo tiles for Christchurch, Addington and Riccarton, and have started working on ones for Waltham, Linwood, Opawa and Woolston. These ones should be ready in a couple of days. Then after that we still have, as far as Greater Christchurch goes, to look at Lyttelton, Heathcote, Middleton, Sockburn, Hornby, Islington, Weedons and Rolleston on the MSL; Prebbleton and Lincoln on the Hornby Line; and Bryndwr, Papanui, Styx, Belfast, Chaneys, Stewarts Gully, Kainga, Kaiapoi, Flaxton, Southbrook and Rangiora on the MNL, to complete all of the stuff for GC.

Research has shifted to the GC area as well. After a break from the Midland Line work is starting with Christchurch Station which will take about 3 weeks to complete with over 100 files to view. The plan is to look at every station within the GC area in order to be able to fully detail the maps being drawn of the area.

Tuesday, 13 August 2019

Project Diary 2019-08-12

This week we have switched back to the Christchurch area maps due to the impeding local government elections. We are currently working with several candidates and preparing material in order to assist some of their campaigns, in association with Christchurch Transport Blog.

Because of this the Midland Line work has temporarily halted, although research at the local branch of Archives New Zealand has continued. We estimate approximately two more days of research at Archives will be sufficient to complete the Midland Line maps, but are unsure exactly when these maps will actually be ready.

We are taking the time to complete more of the historical maps of Christchurch as well as some of the other stuff we are doing so I have pulled up a number of Gimp projects and revised them as necessary to keep them within reasonable file sizes. For the Main North Line it is now split into one project that covers Addington and Riccarton along with Christchurch (from MSL) and a second one covering from Bryndwr to Ashley, previously it was all one project from Addington to Ashley. 

For the Main South Line we have Lyttelton to Heathcote including Ferrymead in a project, then from Woolston to Waltham, then from Middleton to Hornby, and then from Islington to Rolleston. The reason Christchurch was put in with Addington going north to Riccarton was because we had Addington in two projects, one for the MNL and one for the MSL, which was an unwarranted duplication.The one we haven't started on really is Hornby to Lincoln, and it's likely we will take Hornby out of the MSL Gimp projects at this point and put it into the one for the Hornby Industrial Line.

It's timely to comment briefly about maps of local government boundaries. Linz Data Services does not have this type of map in the list of layers that can be downloaded through their site on Koordinates. However, Statistics New Zealand, another Government department, does have them through its Datafinder site, http://datafinder.stats.govt.nz also hosted on Koordinates. As a result we have taken the opportunity to download six layers together: Maori Constituency 2019, Constituency 2019, Community Board 2019, Regional Council 2019, Territorial Authority 2019 and Ward 2019. This information is needed in order to discover the boundaries of each of the wards for the Regional Council elections and in so doing, be able to assist certain candidates in the wards of the transport related issues in their constituency.

Saturday, 10 August 2019

MSL Branches [17A]: Bluff Island Harbour


This week we took a little side trip to have a look at Bluff with the NZR aerial photos from 1972-3 covering the island harbour as well as the land based station yard. Like many ports, Bluff once had extensive shipside trackwork on the wharves that is no longer needed in this era of containerisation. As a result their rail network is much less extensive than formerly, aided by the shift to road transport and traffic being railed between Southland and other regions' ports to suit shipping patterns.


 Starting off with our usual pair of overview maps showing how things have changed over a 40-plus year period.

Our first maps are the island harbour. We don't know much about this structure, when it was built or for what purpose. Most ports have a series of wharves that jut out from and at right angles to, the shoreline. The "Island" is very unusual in NZ, and made for an interesting and unique rail layout. The westernmost tip as you can see was notable for the railway engine turning triangle, which is now gone.

Going east along the island, we get into one of the wharves, with a storage shed and attendant sidings. Ship-side sidings were very common on NZ wharves once, but have mostly disappeared since containerisation made it unnecessary to directly unload to railway wagons. Often times tracks are still in place on parts of wharves, but here there is just a single siding still connected and usable.

 More into the middle of the island is the main railway storage area. However the large yard with its multiple sidings has been largely reduced to the main line and a couple of tracks.

The south-eastern part of the island had several wharves along with their numerous tracks. Scissors crossings and other complex track structures such as double slips were commonly seen on wharves back in the day in order to fit as much track space as possible into a cramped layout. These days all but gone with just a couple of tracks across the whole area.

We can now have a look at the main railway station and yard at Bluff. The curve taking the main line across the bridge to the island harbour is to the left. Even in the 1970s there were few sidings in this area. The island section became the main line a long time ago and the Bluff township area a siding off it.

A little further east we come to the main railyards and some industrial sidings. These days practically everything is gone. 

Here we can see a shore-based wharf and a couple of industrial premises served by wagon turntables. These were once a popular way of getting into premises with a track and space saving layout, but fell from favour as longer and heavier wagons became more prevalent. The wharf was very interesting as there were no fewer than three separate tracks crossing between it and the shore, two of which can be seen in the black and white historical map. This was a necessity to connect up all the tracks in the tight space available, but these days, with no shipside tracks needed, the connecting lines and even some of the bridging has gone.

 Closeup views of the two sets of private sidings connected by wagon turntables. In the first photo we can see another track coming out of the front of one of the premises (far left) that appears to have been disconnected. The right hand premises in the same map is interesting as it was connected directly without a turntable.


Lastly we can see the end of the line where it went down to the tank farm and simply stopped adjacent to what was then the famed Fluteys Paua House. This area is known as "Bluff Township Siding".

Friday, 2 August 2019

Project Development Report [2019K]

This brief report is to update progress for 2019 so far as the year is now more than half over.

At the start of this year work was happening on the MNPL line which continued until the end of January and then work was switched onto the Main North Line, followed by the Kinleith Branch, North Auckland Line, then parts of the Main South Line around Dunedin. Then we had a look at Hamilton on the NIMT, followed by a significant chunk of the MSL within Canterbury. The next section to be looked at was the Cromwell Gorge.

At the start of June, work was begun on the Christchurch specific project in conjunction with some of the other areas that we support, and the Midland Line work was started towards the end of that month. Since then, work has alternated between Christchurch and the Midland Line.

It seems a good move right now to push ahead to complete Volume 9 for the Midland Line over the month of August, alternating with the Christchurch specific project as necessary. 

In terms of the overall project and its goal to have all 12 volumes completed at a basic level by the end of this year, that hasn't really fired, however neither has the alternative preference of completing any volume at all. We are now substituting an alternative schedule, which is to prioritise the South Island volumes of which we have six, to be completed first at whatever level seems appropriate, which will be more than basic. This includes revising Volume 7, the Nelson Section, with inline yard layouts and other detail using the aerial photography we previously obtained, which was put into an appendix at the end of the most recent edition of the printed volume.

However it is possible to work on the North Island maps by using WMTS to pull in live aerial layers of any area without the extensive work that is needed to download map layers for offline use, so using this to complete any area of the North Island to the Basic level that we proposed could make it happen a lot faster than has been the case to date. 

The priorities have shifted from first completing all of the maps to the Basic level in 2019, to completing as much as possible of the South Island at intermediate or comprehensive level before completing the Basic maps in the rest of the country. Some intermediate or comprehensive work of the North Island will continue throughout next year, especially for the Palmerston North Gisborne Line. Basic maps for North Island areas will also continue this year but we can't say how complete that will be by the end of 2019 at this stage.


Midland Line [0E]: Volume 9 Progress Report 5

This is a brief update on progress with Volume 9. Currently we have completed the route alignment as far as Otira and the details of the Otira yard tracks are being drawn in. A decision has been made to use the available aerial photography we have as far as Kotuku to draw layouts of all stations for which the photographs cover west of Otira.

Route alignment which consists of drawing tracks and station markers is one stage of the mapwork and the second stage after that is to put in bridges, tunnels and milepost markers where applicable. We expect to push on with route alignment towards Stillwater, Greymouth, Hokitika and Ross, although the last section is mostly done already, so there isn't a lot to be done in that respect.

Visits to Archives New Zealand over past and coming weeks will fill in in the details of the major yards of Stillwater, Greymouth, Hokitika and Ross in lieu of any available aerial photography. We hope this should enable Volume 9 to be completed by the end of August.

 The location of Bealey Bridge is an interesting question. Working Timetables and Kiwirail maps place it on the eastern end of the bridge as shown to the right corresponding to 68 miles 45 chains. However NZR file information shows the placement of the passenger stop at the western end of the bridge corresponding to 69 miles.

The other question is the location of Bealey Quarry and at this stage we are not confident of being able to determine that with our current level of research.
 Apart from the ballast siding at Waimakariri Bridge there was also one at Cora Lynn for a period probably around the 1940s which is likely to be the one with wagons in it shown above. This was not a source of high quality ballast and was only used for emergencies.
Another location where ballast was taken along the Midland Line was Sawmill Stream at approximately the location shown above. Probably this dates from the construction days and only one reference to it from 1923 has been found so far.

Wednesday, 31 July 2019

Midland Line [4B]: Arthurs Pass-Otira 2: MRC Summit Line 2

Following on from last evening's post here is the rest of the Summit to Otira route. We are assuming plans will exist for the climb up from Arthurs Pass Station to the summit as there are many plans in the Archives collection, but few of them have been scanned as yet which will make it necessary for us to go through much of the remaining collection in the reading room whenever we have time. Of the ones that have been accessed so far we have been able to source the entire route down to well beyond Otira (at least 12 miles) and have used plans and drawn the route as far as where it comes alongside the existing route (5 miles) as the plans beyond that point are difficult to align to topography because they are so old.

Starting from the summit (the actual pass known as "Arthurs Pass") at 920 metres ASL and with a railway station marked as "Summit Station", the proposed line begins to descend towards Otira. The initial section being right alongside the highway and passing Lake Misery, the gradient here being 1 in 15.
At the 1 mile post the line has descended about 100 metres.  Shortly thereafter the location of "Kopeki Station" is reached. It's not immediately obvious why another station was needed so close to the summit. The origin of "Kopeki" is unclear, but there is also a creek of that name marked on the plans, which is what is known today as Pegleg Creek.
Kopeki Station would have been about where the road used to head up the zig zag. This notorious feature of the highway for more than 100 years was replaced in the 1990s by the present Otira Viaduct. At this point the proposed line left the proximity of the highway, understandably given the abrupt change in heights where the highway viaduct crosses the bottom of a big slip, and crossing over the top of the present tunnel it follows less undulating terrain further west.
As the proposed line crosses the slip above Park Creek it reaches the 2 mile peg. The altitude is now 740 metres, representing a descent of 180 metres from the summit.
 After crossing over the top of the present rail tunnel again, the proposed line reaches the site of "Flat Top Station". This was to have had a separate yard as a spur off the main line. The route then makes a big curve westward before it reaches the 3 mile peg, now at an altitude of around 640 metres. Again there is the question of why another station was needed so close to the previous one.
We saw this map in the previous post and here it is again. This one is scale 1:8000 (the others are scale 1:5000) to fit the entire curved section in, which would be extremely difficult to show otherwise. At 4 miles the altitude on the surface was 810 metres, underscoring the need for the tunnel to continue the descent through the hillside. Upon exiting the tunnel the 520 metre contour line is crossed and on reaching the 5 mile peg the line has descended to around 500 metres, about 20 metres higher than the present line. Considering that the present route is descending at 1 in 33 towards Otira station, the 1899 line still has to achieve very steep grades to reach Otira and there is a stretch of 1 in 22 along this section. See the comments on the previous post about the grades through the 3-5 mile section of the route. One of the old Midland Railway Co plans (drawn by the actual company) shows "Goat Creek" as the name of the station where Otira is today (at 7 miles).







Monday, 29 July 2019

Midland Line [4A]: Arthurs Pass-Otira Line 1: MRC Summit Line 1

Perhaps a lesser known feature of the original plans for the Midland Line was that the Midland Railway Company proposed a summit line over Arthurs Pass rather than the Otira Tunnel that we have today. The summit line would have run close to the current highway in a number of places and it incorporated gradients of up to 1 in 15 to achieve this.

Archives New Zealand have the drawings that were prepared of this proposed route dated 1899 which is probably the date that the Government received them from the liquidator of the Midland Railway Co, the company having been wound up after it failed to complete its contracted works. It had built the railway from "Brunnerton" (Brunner as we know it today) to Jackson on the western side of the route, but on the eastern side the line that had been started from Springfield was only complete to Otarama, with Tunnel 1 being completed but work yet to start on the Paterson Stream viaduct. There thus remained 92 km of very difficult railway through the Waimakariri Gorge and the Main Divide to be completed. The MRC sought a new contract in 1894 under which it would have undertaken to complete this section within a four year period but this was rejected by the government and eventually the works were resumed by the PWD. Otira was reached in 1900 from the western side, and on the eastern side, Otarama to Broken River was completed in 1906, Broken River to Cass in 1910, and Cass to Arthurs Pass in 1914. By that time the work was well in hand for the Otira Tunnel. This work was commenced in 1908 by the private firm of John McLean & Sons and was intended to be completed within four years. However at the time of expiry the company had completed less than half of the tunnel and the work was again taken over by PWD. Hole-through occurred in 1918. It was to be another three years before excavation and lining was completed, and in 1922 the rails were completely laid. The Midland Line was finally finished and opened to through traffic in 1923.

At the moment we have accessed drawings of the summit route from the top of Arthurs Pass down to Otira, approximately 6 miles. The below map shows the route coming down the Rolleston River valley with a big horseshoe curve and tunnel. 

 The route as shown with aerial photo background where it approaches the present day route.

By turning off the aerial photo background we can look at the contour curves with their heights marked in metres and gauge some idea of the way the railway climbed/descended. There does appear to be some sort of altitude markings on the drawings but we need to do some more work with these before using them. So at the moment we will go with the contour curves and what is marked on the drawings for gradients. At the bottom of the drawn section, 5 miles from the summit, the altitude is about 500 metres, while at 3 miles, it is 640 metres. This implies an average gradient of about 1 in 22 over that section. The gradients marked on the diagrams vary. From 3 miles the line is descending on 1 in 15 until just before the start of the tunnel, where the line levels out for the bridge over the Rolleston River (not marked). The tunnel itself is at 1 in 15 for a length of 1170 yards (1 km). At the bottom of the tunnel there is a longer level section which includes the bridge over Holts Creek (not marked) before a descent is resumed towards Otira at 1 in 15.

It will be interesting to put together the rest of the diagrams in the next few days to see what the line would have looked like as it came down from the summit and hopefully also the climb from Arthurs Pass up to the summit can be drawn in due course.

Tuesday, 23 July 2019

Midland Line [2H]: Rolleston-Arthurs Pass 8: Avoca 2

Today we are going to have another look at Avoca, this time with a full set of maps.
An overview of the Avoca area, showing the full area of interest including the locations of the coal mining.

Avoca railway station. This was still open as a crossing loop until the 1980s.
This backshunt and the scissors crossing were part of the sidings installed for the coal mining and were removed after it closed.
A closer look at the station showing the main features. The coal mine had a weighbridge and loading stage that were removed when it closed.
1982 historical view of the station. Showing that the loop and siding remained the same size as they were in 1923. The original shorter loop was extended in time for the opening of the Otira Tunnel as it was the case that many of the facilities in various places in the Midland Line, such as the Springfield deviation, were improved in time for the opening of the full route.
Looking at the route of the tramway that was installed for the coal mine. The section just above Avoca station was an incline worked by endless rope haulage  to bring the coal tubs down to unloading. Whereas the main part of the route going across the map from left to right was worked by a small steam locomotive.
There was another incline to bring the empty coal tubs down into the Broken River bed to reach the coal mines. A large steam boiler was located at the top of this incline to work the haulage rope that took the empty tubs down and brought the full ones up.
The larger part of the coal mine was on the south side of Broken River. Within the area shown there were two distinct sections of mining, each accessed by its own tramway crossing the river. The earlier and larger section was to the right and the later and smaller section to the left, probably as a new exploration after the main mine caught fire.
Another area that was mined was on the north side of Broken River reached by an extension of the tramway that ran along the riverbank. This appears to be an earlier part of the mine. The mining company was in operation in total for ten years, from 1918 to 1928 (a note on one of the plans shows the date April 1928 "Mine Abandoned").

Sunday, 21 July 2019

Midland Line [2G]: Rolleston-Arthurs Pass 7: Avoca 1

Description of the Mt Torlesse Colliery (currently this area is being mapped and we hope to have more details of it in a few weeks)

"The first coal will be loaded into railway trucks at the company's siding, Avoca, today... the construction of tramway and plant has been a big undertaking...the deep rock cuttings and ravines over which the tramway passes necessitating building several large viaducts...on account of the very steep gradients heavy machinery for haulage purposes had to be employed...

The transport of coal from the mine to Avoca railway station is by light tramway, the through route being about 3 3/4 miles...beginning from the mine, the coal is taken down the Broken River for a distance of three quarters of a mile to the foot of an incline...from there it is raised by endless rope haulage up a steep incline with an average gradient of 1 in 2 to a height of 850 feet from the river level...from here it is taken 2 1/4 miles by locomotive to a point 450 ft directly above the Avoca station...here it is lowered down a steep incline by gravitation to the bins of the company's siding...the plant is capable of handling an output of 500 tons daily...

https://paperspast.natlib.govt.nz/newspapers/LT19180518.2.55

From other sources, the company was in operation for nine years only, from 1918 to 1927. The best year of operations being in 1920 when 15770 tons, an average of only 300 tons per WEEK.  The total output was 72,500 tons over the full period of operation. 500 tons a day would have been a very major undertaking. The coal tubs used were said to have a capacity of 12 hundredweight, or about half a ton, so there would had to have been 1000 loads a day moved to get 500 tons, again a pretty major undertaking. Whilst there was some suggestion that two trains a day would have been needed to handle all the output proposed, it seems doubtful that more than one train per week would have been necessary. The mine did well for a time but in 1924 there was an outbreak of fire in the underground workings, and further similar issues plagued the mine from then on, so that it was eventually forced to close, and the company placed into liquidation.

The loading stage and siding at Avoca in 1920. Photo by Edgar Williams, Alexander Turnbull Library.

Friday, 19 July 2019

Midland Line [2F]: Rolleston-Arthurs Pass 6: Waimakariri Bridge 1

Waimakariri Bridge is a location on the Midland Line. It is one of three crossings that the Kiwirail network has historically made of the river, all on different lines; the others being the Main North Line near Kaiapoi, and the Oxford Branch near Bexley (closed in 1930 but the bridge still stands today). Here is the overview map.
 There are two key features of this location: the bridge itself which was replaced in the late 1970s on a new alignment; and the ballast pit on the north bank of the river.
 The new bridge is concrete and was built on a new alignment slightly easing the curvature here (14 chains radius).
 On the north side was the ballast pit.



Development of the Waimakariri Ballast Pit began in 1941 due to an anticipated requirement of large scale reballasting work being needed on the Midland Line in the coming years, however it was not until 1944 that the pit was fully in operation with a dragline and crushing plant. Operations at the pit were suspended about 1953 and the plant was removed the following year. The date at which the site was finally closed off and cleared has not been ascertained. The historical aerial photos used in these comparisons were taken in 1966 at which time track was still in place in the two locations shown.