Intro

It is Christmas 1953 and New Zealand is mourning a tragedy. An intercity train from Wellington, New Zealand, never arrived at its destination Auckland. The missing train was the victim of a flood which caused a bridge collapse across the Whangaehu River. wThunga-eyhu 151 would perish as the train was plunged into the river below the bridge. The event would go down as one of the worst in New Zealand history and as one of the most unfortunate turn of events as if the train was just a few minutes earlier or later then disaster could have been averted. Today we are looking at the Tangi-wai disaster wait to the end to see if you will agree with North Island Main Trunk is the main railway line on new Zealand’s most populous north island.

Background

The line connects the country's two main cities Auckland and Wellington. Completed in 1908 it is a marvel of Victorian and 20th century engineering, The line spans rivers, climbs mountains and passes over vast viaducts. One such crossing is near the small rural village of Tangiwai on the Whangaehu River. The river flows down the mountain side from Crater Lake for approximately eight and one-half miles in an easterly direction, then turns towards the south at the bottom of a fan, runs more or less parallel with the Desert Road for approximately six miles, thence in a south-westerly direction towards Tangiwai. The total distance to Tangiwai is approximately twenty-five miles. The river flowing down from crater lake created a risk and that was erosion of its fragile ash banks, which in turn would release large quantities of water down the river channel. The violence of the flow would also take with it large quantities of material, creating a lahar, a violent type of mudflow composed of a slurry of pyroclastic material, rocky debris and water. Needless to say this can be horrendously destructive, washing away anything in its path. The river was spanned by bridge no 136, it was built around 1906, by the public works department. The bridge was built to a generic standard design used elsewhere in the country, it stood at a length of 198 ft and made use of steel construction supported by with 8 concrete piers. The spans consisted of from north to south 1/22 ft. 2/44 ft and 4/22 ft. plate girder spans. The bridge design would be criticized later on in that the piers had insufficient foundations and piers 5 and 7 were superfluous for structural integrity and even hinder the flow of water along the river. But we will come back to this later on. The bridge would suffer a number of damages throughout its working life, which required repairs to its foundations and piers. The first of such damage occurred in 1925 when a 9ft swell made its way along the river causing a scour on pier 4s upstream-side above its footing, this caused the track on the bridge to be mis aligned and resulted in a 1⁄2 inch movement of the structure. To fix the damage rocks were placed into the scour, but this wouldn't be the last time the bridge suffered damage., Just over 10 years later in march 1936 the Foreman of Works reported scour at Piers Nos. 3 and 4. He recommended 15 wagons of stone protection. This work was completed on 18 June 1936. Pier 3 would be damaged again in february 1944 after a flood and whirlpool scoured a hole 10 ft. in diameter and 3 ft. deep on the upstream side of the pier In june 1946 engineers suggested placing eight 5-ton concrete protective blocks in the vicinity of Pier No. 4, to offer protection from floods and debris, the project was completed in july the same year, the bridge was closely monitored for the next couple of years, but no other issues were reported. Which leads us on to train 626 departing Wellington enroute to Auckland at 3 p.m. on the 24th december 1953.

The Train

///// Train 626 consisted of a KA class steam locomotive hauling eleven carriages: five second class, four first class, a guard's van and a postal van, that evening the 467.3 ton 704 ft formation was carrying 285 passengers and crew. Many aboard are holiday makers, and as the evening set in many had settled down for the night, at around 1020pm the train passed through Tangi-wai at what eyewitnesses on the station platform thought to be slower than usual at around 40mph. For reference the line speed was 50mph, apart from being slower than usual nothing else out of the ordinary could be seen as the locomotive and its rake passed through. Just 1 mile down the line was bridge 136 and its span over the Whanga-ehu River.

The Disaster

As the train approached the Tangiwai end entrance to the bridge the engine crew saw a man alongside the track waving a light, strange they thought but soon enough the reason became apparent. As the headlight of the locomotive washed over the bridge ahead a section of the track ahead was missing, but what couldn't be seen in the December darkness was that a whole section of the bridge had completely failed sending some of the structure into the whangaehu. Immediately the driver and fireman applied the emergency brakes, but it was too late as the train couldn't stop in the distance of available track. The locomotive tender and first 5 carriages went careering off the bridge plunging into the river below. The remaining three first-class carriages, the guard's carriage, and the postal carriage remained precariously on the track. Cyril Ellis, the man who was waving the light by the side of the track to warn the train of its impending doom, approached the guard and explained what he had seen. The two men made their way to the 6th carriage, the first first class carriage which by now was teetering on the edge of the damaged track, and attempted to evacuate the passengers onboard. They, with the assistance of a passenger, managed to evacuate 24 people by smashing out the windows. One person wasn't so lucky, as the coupling of the carriage failed, resulting in the carriage rolling into the river.

Aftermath

148 lives were lost to the river, including the driver and fireman; 22 of the victims' bodies would never be recovered. 5 miles away the Wai ow ru Military Camp dispatched soldiers to assist in rescue operations, along with rescue teams. By midnight the first survivors were evacuated to Waiouru, a few hours later the first of the dead were recovered and sent to a makeshift morgue. More of the dead would be pulled from the river downstream by locals and farmers, giving a grim awareness of the disaster. 60 of the victims bodies would be recovered in such ways, but the unrecovered victims are thought to have been washed out to sea. As many awake for christmas morning the news is broadcast across the country, and the public is made aware of the full scope of the tragedy. With so many dead, and an apparently sudden unexplained disaster on one of the country's most important railway lines, the question of how has to be asked. Soon after the tragedy, investigators are dispatched to the site to pick over the wreckage and collapsed bridge.

Investigation

Upon seeing the locations of the carriages and the missing span of the bridge, investigators concluded that the failed 22ft steel girder span must have failed before the train had begun its passage on the bridge, and thus hinting at something other than the train to be the cause of the collapse. The bridge had the top portion Pier No. 2 broken off, and this was lying under the bridge between Piers 1 and 2. Pier No. 3 was smashed above the base into at least four pieces and pier 4 was completely missing, having been broken into multiple pieces. Piers 1, 6, 7, and 8 were not damaged. But what was the cause of the dramatic damage to the piers. Well, investigators looked into the bridges past and this pointed to the likely cause to be further upstream at the crater lake. You see the beginnings of the 1953 disaster goes all the way back to March 1945 and Mt Ruapehu's Rua-pe-eU eruption, the debris from this formed a naturally occurring tephra dam at the crater lake, which in turn caused it to fill with water. Eventually this dam would be insufficient to hold back the lake, and sadly the tipping point was the 24th december 1953. The dam failure released water from the Crater Lake through an outlet cave beneath the Whangaehu Glacier. The was channelled down the Whangaehu River carrying with it a high content of ash deposited from the 1945 eruption and blocks of ice due to the collapse of large volumes of the glacier. This torrent of effluent smashed into the previously weakened bridge causing pier 4 to fail, sending the span into the river. The investigators had to deal with questions on the bridge's original design's suitability for the area, but an earlier fire at government buildings before the disaster had destroyed the plans. But what we do know is the bridge wasn't suitable or seriously weakened enough for this particular lahar. The disaster would improve safety in the area, as the New Zealand Railways Department would install a lahar warning system upstream to alert train control to high river flows, needless to say this was lacking in 1953. The Passerby who alerted the train Cyril Ellis and passenger John Holman were awarded the George Cross for their bravery that day. And guard Inglis and a passing traveller, Arthur Dewar Bell, both received the British Empire Medal for their actions that saved fifteen lives. Sadly the disaster was a pure accident of bad luck, although the bridge was likely deficient, if the train was early or really delayed the tragic loss of such life might not have happened. The bridge would be rebuilt, reconnecting the vital railway line.

Rating

So the disaster I’m going to rate here is 7 on my disaster scale and also 7 on my legacy scale, do you agree? Let me know in the comment below. This video is a Plainly Difficult production. All videos on the channel are creative commons Attribution-ShareAlike. Plainly difficult videos are produced by me John, in a sunny Southeastern corner of london, uk. Help the channel grow by liking commenting and subscribing! Check out my twitter for all sorts of photos and odd and sods, as well as hints on future videos! I've got patreon and youtube membership as well so if you fancy check them out! All that's left to say is thank you for watching! https://www.environmentandsociety.org/arcadia/lahar-meets-locomotive-new-zealands-tangiwai-railway-disaster-christmas-eve-1953