Soviet Union-The Baykal-Amur Main Line

The vast Siberian region between Lake Baykal and the lower Amur River, called the Transbaykal (or Zabaykaliye), is rich in natural and mineral resources. Yet until recently, it lacked adequate transportation to the rest of the country. Its main communication artery was the overburdened Trans-Siberian Railway (see Glossary), running well south of it. Although providing the Transbaykal region with a railroad was considered in the nineteenth century, work on the Baykal-Amur Main Line (Baykalo-Amurskaya Magistral'-- BAM; see Glossary) did not begin until 1974. The BAM was finally opened in 1989.

Survey and construction crews overcame formidable geological, climatic, topographic, and engineering challenges, including rivers, ground ice, unstable soil, seismic areas, mountains, and extremes of cold and heat. About two-thirds of the BAM trackage crossed areas of ground ice that caused frost heave and other unstable soil conditions. In the summer, permafrost created large bogs that hampered roadbed construction, and embankments sank into the marshy terrain during the summer thaw. To prevent such problems, engineers insulated the strip of marsh along the tracks to keep it in a continuously frozen state. Seismic activity along some 1,000 kilometers of the line also caused problems, triggering avalanches and landslides. Topographic obstacles were formidable as well. To cross the mountains, crews had to pierce over thirty kilometers of tunnels. The BAM also crossed more than 3,000 streams, and because of the permafrost new bridge construction techniques had to be devised. On average, the roadbed for the BAM required moving 100,000 cubic meters of earth--either cutting or filling--for each kilometer of track.

The mean annual temperature along the BAM ranges from -10°C to -4°C, with extremes of -58°C in the winter to 36°C in the summer. To operate their trains under these severe climatic conditions, the railroads used special equipment, locomotives, rolling stock, and fixed installations. Snow plows, snow-melting machines, switch heaters, and other specialized equipment were indispensable in the winter. Rails made of special steel that does not become brittle at the very low temperatures of the Arctic and Siberian winters were also used.

From its western terminus at Ust'-Kut to its eastern end at Komsomol'sk-na-Amure, the BAM stretched for 3,145 kilometers, between 180 and 300 kilometers north of the Trans-Siberian Railway. It had a total of 5,000 kilometers of main line and yard track. In addition to the east-west main line, a 402-kilometer perpendicular line, the "Little BAM," ran from Bamovskaya on the Trans-Siberian Railway north to Tynda on the BAM and thence to Berkakit to serve the important mining and industrial area of Neryungri. In the late 1980s, an extension to the Yakutiya region, rich in timber and minerals, was under way.

The BAM and its feeder routes, both rail and highway, served an area of approximately 1.2 million square kilometers. Although track laying was completed in 1986, it was not yet in full operation in 1989. The projected freight traffic on the BAM was planned at 35 million tons per year, with trains of up to 9,000 tons. Moreover, the government planned for the BAM to become an important part of the Siberian land bridge from Japan, via the port of Sovetskaya Gavan', to West European destinations, saving 20 percent in time over the maritime route.

Data as of May 1989