Maimai Siding

Maimai (~50 km) is a small locality on the Stillwater Ngakawau Line, near Reefton (~62 km). It is divided from the latter by the Reefton Saddle. Suttons Mill operated at some past time to the north of Maimai with a bush tramway. Maimai is just before a 70 degree bend in both the railway and State Highway 7 which are parallel at this point. Just downline from Maimai is the bridge crossing the Mawheraiti (Little Grey) River. Maimai is the last location before Reefton that is in the valley of the Mawheraiti River, therefore the last bit of flat land before a train has to climb the Reefton Saddle, pass through the Tawhai Tunnel and descend again to Reefton.

Birchfield Coal established an opencast coal mine at Giles Creek in 1984 and the operation has developed to produce 500,000 tonnes of annual output. The mine is situated in the Rotokohu Coal Measures at an altitude of about 200 metres on an escarpment directly overlooking the Inangahua River Valley. Due to the topography and lack of bridges across the Inangahua River, road access to Giles Creek Mine runs on a north south alignment, towards Maimai, rather than heading east towards Reefton (or more correctly, Cronadun). From Maimai, the route goes north for the first ~7.5 km on the sealed Maimai Road. Reaching the turnoff to the mine, the road climbs steadily through forest to reach the mine after about another 7 km. All of the mine’s output is trucked via Maimai as there is no other road access. Here is an area map of the country between the Mawheraiti and Inangahua Rivers.

Due to the proximity of the railway line to Maimai and the desire to rail coal for customers, a loading facility has been established at Maimai, consisting initially of a loading bank made out of old highsider wagons (similar to the loading bank at Waimangaroa for Denniston coal traffic that closed in the mid 1990s) with a single ended siding. The map below shows the layout.

Fonterra has contracted to bring coal from Maimai by rail to its new dairy factory at Darfield. The siding is now being redeveloped and may have a different final layout to that shown above.

Maimai is one of numerous locations on the Stillwater Ngakawau Line and Midland Line and their branches where coal is or has been historically loaded for customers. Some of the other locations for coal loading include Stillwater, Rapahoe, Dunollie, Rewanui, Reefton, Westport, Rahui, Cascade, Waimangaroa, Conns Creek, Ngakawau, Granity, Summerlea, Seddonville, Mokihinui Mine, Ikamatua,  Ngahere, Blackball, Brunner. As of today, active locations include Ngakawau, Reefton, Maimai and Stillwater, while Rapahoe may be mothballed due to closure of the Spring Creek Mine (except for other possible Solid Energy production such as at Strongman or future new production at Rewanui). Sergeants Hill is proposed as a loading point by Bathurst Mining which is establishing new opencast production at Denniston.

Acknowledgements to the Newzealandlocomotives group for contributions.

The five faces of Paeroa Junction

Well the previous article said there were only four. But things got more complex because there were two different bridges across the river between the junction and Paeroa town. So here are five faces of Paeroa Junction.

N.B. The parts that were operational at each image are in red, parts in black did not exist or operate at the time.

In 1898, the railway from Frankton to Paeroa opened. A single track wooden bridge was used to cross the Ohinemuri River south of the town. The railway station was a little north of this bridge.

In 1905, the branch line to Waikino was opened. This needed a curved track towards the east which had a set of junction points just to the south of the bridge. The signals over this set of points were controlled by a signalbox and ground frame at Paeroa station.

In 1925, stopbanks were constructed along the banks of the Ohinemuri River. This meant the railway bridge had to be raised about 8 feet (2.5 metres). This made the gradient from Paeroa railway station to the bridge severe, so that it was decided to move the station 1 km further north to ease out the gradient. Therefore it was also decided to move the junction of the two lines to the north side of the river. This meant the new bridge had to be built for two tracks, and it was opened in 1926. The track from Frankton was on the west side of the bridge, and the track to Waikino was on the east side of the bridge. The new bridge was constructed of steel girders replacing the wooden Howe Truss original. Within two years the East Coast Main Trunk was completed. All through trains had to go into Paeroa and were then reversed to continue their journey. This did not matter much as steam engines had to be serviced at the locomotive depot, and an extra engine could be attached at Paeroa for trains heading to the east if it was needed. Because of the loss of the passenger station just to the north of the bridges, the new flag halt of Paeroa Township was opened in 1932 at the location of the old station. Only one platform and shelter were provided so that passengers could only board trains travelling on one of the tracks.

In 1959, traffic on the line was increasing because of the output of timber processing plants at Kawerau and Kinleith, which had been built earlier the same decade. At the same time, dieselisation of the ECMT meant that the locomotive servicing stop at Paeroa was not as essential any more. It was decided to shift the junction of the two lines south again, by opening a new station at Paeroa South. A deviation in the eastward route was made to make room for the new railway yard at this location. The direct link from Frankton to Paeroa was removed and all trains to or from the Thames Branch had to reverse at Paeroa South. ECMT trains had a direct connection to Frankton via the new south curve and saved about 5 km in distance and also in time by being able to run straight through instead of reversing. Paeroa Township station was closed, while Paeroa became a station only on the Thames Branch. The second track and bridge between Paeroa South and Paeroa were no longer needed and were removed.

In 1978, the Kaimai Tunnel opened. This resulted in the closure of the railway between Paeroa South and Katikati and it was lifted about five years later. In order to continue with the Thames Branch, which was now extended by 43 km back to Morrinsville, the new ECMT junction, the direct link north to south needed to be reinstated. This was installed as the new curved route shown rather than the more direct link of 1898 to the west. Some say that the original formation had been built on in the intervening 19 years, while others suggest the curved route needed less new track laid and reused the existing level crossing of SH26. Paeroa South station was closed, and most of the track to Apata was eventually lifted, except for the section now owned by the Goldfields Railway between Waihi and Waikino. The track between Apata and Katikati stayed open for several years after 1978 but a railfreight terminal proposal at Katikati came to nothing.

The sixth face (not illustrated) happened after 1995 when the Thames Branch closed. All track and most structures on the branch were removed beyond Waitoa. Railfans can still trace some of the site of the junction and branch today. The most notable remnants on the entire former ECMT route and Thames Branch today are

• The Te Aroha railway station building preserved at its original site.
• The bridge just to the south of Te Aroha.
• The Thames railway station at its original site.
• The Karangahake Tunnel which is part of a public walkway, along with the old railway bridge at the east end.
• The station at Athenree which was relocated to the nearby site of Athenree Historic Homestead.
• The Paeroa station which was taken to Waikino as part of the Goldfields heritage railway project.
• The Waihi station on its original site as part of the Goldfields heritage railway project.
• A culvert just east of Waihi where the railway crossed over a tramway
• Between Katikati and Apata some of the larger bridges are still in place, used to carry power lines.

The four faces of Paeroa

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.