The destruction of the railway
Foreign Office view is that the railway should be sold to the Siamese at the best possible price obtainable which should include compensation for the labour employed on the construction.
[Telegram, British Foreign Office to British Embassy Bangkok, 5 July 1946, cited in Paul H. Kratoska, The Thailand–Burma Railway, 1942–1946, Documents and Selected Writings, vol. II, London, Routledge, 2006, 126.]
Despite the immense human cost of its construction the Burma-Thailand railway was demolished after World War II. Only about a quarter of it, in Thailand, was later reopened.
In 1944–45 the railway performed its planned role of supplying Japanese forces in Burma even though Allied bombing caused extensive damage, including to the steel bridge at Kanchanaburi, later known as 'Bridge on the River Kwai'.
When the war ended the railway continued to be used to transport Allied prisoners of war and Japanese troops from Burma (now Myanmar) to Thailand and Malaya. It was also used by the Allied War Graves Commission survey party as they searched for the remains of the prisoners of war who had died at camps along the railway's route during the war. At this time the railway was administered by the victorious Allied authorities, specifically by Lieutenant-Colonel K. A. Warmenhoven, a Dutch officer with railway experience.
In determining the future of the railway the Allied authorities faced two questions. The first was whether it was desirable to maintain this link between Burma and Thailand. Some British officials thought the railway was strategically valuable but doubted whether Burma, which was just gaining its independence from Britain, would have much use for it. The terrain meant that the railway would be extremely difficult to maintain and its commercial benefit, given the availability of sea transport, was low. Even in October 1945 the Allies found that the railway was in poor condition and would require considerable investment to restore. To quote a report from October 1945
[the railway] was not constructed in permanent form … some of the 688 bridges on this railway are too weak to carry locomotives, wagons having to be moved over them singly by hand; many of these bridges are liable to be washed out during the monsoon season. Under present conditions, therefore, its capacity is negligible.
[Report by Allied Joint Planning Staff, 4 October 1945, cited in Paul H. Kratoska, The Thailand–Burma Railway, 1942–1946, Documents and Selected Writings, vol. II, London, Routledge, 2006, 126.]
The second issue was that of reparations. In addition to recruiting and conscripting many thousands of Asian labourers (rǒmusha) the Japanese had commandeered locomotives, rolling stock, railway track and other materials and equipment from across the territories they had occupied in South East Asia. The materials for the 'Bridge on the River Kwai', for instance, were taken from an existing bridge in Java in the Netherlands East Indies. Some restitution for these losses was required.
By 1947 therefore the Allies had decided that the railway on the Burma side would be torn up, while the remaining portion in Thailand would be sold to the Thai government for £1.5 million. The revenue thus raised was allocated to those countries entitled to reparations. Much of the material used on the railway was returned to its origins, though some of its infrastructure, including the 'Bridge on the River Kwai', remained.
The Thai Government made use of the materials from the railway throughout Thailand and decided to close the railway. However, in 1957 it reopened a 130-kilometre section between Nong Pladuk and Nam Tok (with a feeder line to a popular waterfall at Sai Yok Noi). This continues to run today servicing the local community. The section from the 'Bridge on the River Kwai' in Kanchanaburi to Nam Tok is also very popular with tourists who 'Ride the Death Railway' through evocative wartime sites such as the two Chungkai cuttings and the Wampo viaduct.
Beyond the terminus of the railway at Nam Tok much of the railway's route is invisible, lost beneath agricultural land and the jungle. However, with local knowledge the impact of the railway on the landscape of the wartime route can still be discerned.
It is unlikely that the full railway will ever be restored. Any extension of the line beyond Nam Tok would face the same challenges as did the Japanese and their workforce in World War II. Moreover, a significant portion of the railway route, between Tha Khanun and Sonkurai, has been submerged since 1985 under the Vachiralongkorn Dam. Finally, continuing tensions between Burma and Thailand make the border area sensitive.