這裡有同一段影片：
http://www.youtube.com/watch?v=5wO2sApvTXc

他是寫到：
This tunnel in Russia is the longest in-city tunnel of Europe. There is a
river running over it and water leaks at some points. When the temperature
reaches -38 degrees outside the tunnel like it did this winter, the water
on the tunnel road freezes and the result is the attached video taken
during a single day with the tunnel camera.

過河隧道有些地方漏水, 結冰