With my change of focus today to mapping part of the old ECMT route I got to Paeroa and then started drawing up the notorious junction triangle at the south end. This story is well known but I will repeat it here with these four images.
In all of the images, the red lines are the ones that were in use at the time. The black ones are shown for interest but did not actually exist or were in use at the time. As you will see this was not a triangle as we would ordinarily know it since there were not three legs in use at any one time.
Paeroa in 1898. The Thames Branch had reached Paeroa from the south, and the red route went north to Paeroa and south towards Frankton. A pretty straightforward layout.
Paeroa in 1905. A branch to Waikino (which later became the ECMT) had started to be constructed. Therefore a connecting curve was added so that trains could run from Paeroa to the east.
Paeroa in 1959. In conjunction with the dieselisation of the line, the direct link curve to the ECMT was added. As the direct link to Paeroa from the south was closed, a new junction station called Paeroa South was added, which required a realignment of the approaches to it. All trains for the Thames Branch would now have to reverse or be shunted at Paeroa South.
Paeroa in 1978. The ECMT along with Paeroa South station was closed. The direct link from Frankton to Paeroa was reinstated, albeit on a new alignment because the original route had been sold and built on.
Work will continue on this in the coming week heading out to find the Pokeno-Paeroa deviation proposal of the 1930s (formation was constructed, but never completed). This is well covered on several NZMS 1 maps almost all the way through. This is where you can begin to wonder why it was that this route was never actually completed, certainly most if not all of the formation was surveyed and a lot of work done on it. Info received indicates the work was started 1938 but it was never finished. In hindsight this only moved the junction of the ECMT further to the north and did not address the problems of the difficult Paeroa-Apata section which was addressed by building the Kaimai Tunnel. Post war efforts focused on the latter and the Pokeno-Paeroa cutoff line was abandoned and forgotten.