0265 Ready for the last evening service diesel car kiha 110-134 is waiting at Moichi junction. (2010)
This was a non-electrified line within Iwate Prefecture, 38, 4 km long and for a long time carrying very few passengers, in 2009 only an average of 46 per day. After part of a mountainside broke off and buried the track on 31 July, 2010, with diesel car kiha 110-133 crashing into the debris, traffic on the Iwaizumi-sen ended. Little could I imagine that the line would close less than a month after I had visited it on July 9, 2010.
The collision on 31 July 2010 with the huge heap of rubble that covered the line occurred directly at the exit of one of the tunnels above Iwate Ôkawa in the morning at about 7:35, three of the passengers (of a total of 7 passengers and 2 staff) being lightly injured. Clearing the rubble and securing the location to prevent further landslides took several months, so a salvage train could not reach the derailed kiha 110-133 until 18 November 2010 – this salvage train being the last train ever to run on the Iwaizumi-sen.
The Iwaizumi-sen branched off from the Yamada-sen deep in the mountains at Moichi, 15, 1 km up the valley from Miyako. From Moichi it ran northwards into the lonely valley of the Kariya River, reaching the summit in Oshikado Tunnel (2987 m long). From there the line descended steeply into the valley of the Omoto River and continued there for a while as far as Iwaizumi terminus. A continuation to the coast at Omoto (today served by the Sanriku Tetsudô) was never built.
Construction of the Iwaizumi-sen began in 1942 from Moichi to Iwate Wainai with the purpose of transporting fireproof clay for the production of firebrick (ceramic material used in lining furnaces, kilns or fireplaces). Iwate Wainai to Oshikado opened for freight in 1944, with fireclay being brought by ropeway to Oshikado station.
After the war, Oshikado Tunnel was opened to traffic in 1947 and passenger transport began to the north side of the tunnel. JNR continued the construction of the line, and in 1957 Asanai was reached, 31 km from Moichi. However, the community of Iwaizumi pleaded for the continuation of the line into its centre, construction of this section beginning in 1968. The Iwaizumi-sen was finally completed to Iwaizumi on 6 February 1972 (no freight was handled from Asanai to Iwaizumi terminus).
Soon, unfortunately, there was a sharp fall in passenger and tourist traffic, but as the road from Moichi was extremely narrow no regular bus substitution service could be installed. Rail services were gradually reduced, with no more trains running during daytime as from 1992. Iwaizumi-sen traffic was increasingly included in bus routes through the Iwate mountains, in spite of the difficult road conditions. As shown in one of pictures, only one morning and two evening trains remained in 2010.
The landslide at km 23, 965 on July 31, 2010, brought the end of services. Oshikado Tunnel was transformed into a road tunnel and opened on 13 December 2020. The track between Nakasato and Iwate Wainai is now a rail park with the possibility of enjoying a ride on a four-person rail bike.
The official closure date of the line is 1 April 2014.