Lesnaya (Saint Petersburg Metro)

Proximity to the Baltic Sea and the Neva River delta and postglacial landscape made soils of the future city grounds swampy, which influenced urban development. Underground layers of water and buried river tributaries require thorough geological sounding of planned building locations, which may not be always carried out well. Thus during the original excavation of the two tunnels between Lesnaya and the next station of the line, Ploschad' Muzhestva in early 1970s water rushed into the hollowed underground space. This first washout was stopped with the help of costly innovative liquid nitrogen freezing pumped from the surface over specially laid piping. The construction of the line then was able to continue successfully and the trains were able to run safely after its inauguration for 20 years. Then the tunnels started leaking, and the second washout happened in 1995.

In mid-1990s the line between the two stations leaked, so the traffic first was slowed down and later stopped. The two ends of these tunnel sections were sealed off and the line was cut into two parts of unequal length joined on the surface on the order of city authorities by a free-of-charge bus service.

Several projects of joining the interrupted underground line were discussed. Some of these tried to find horizontal bypass of the emergency area, but they were deemed impractical and replacement tunnel sections were built on a different depth from the original tunnels using an innovative Italian mining complex Victoria. Train movement along the whole Red Line (Line One) was reopened in 2004, 8+1⁄2 years after the washout.^[3]

In 2017 the station had its turn to close for 11-month-long repairs. The building was redecorated, and major works were carried out in the escalator tunnel, as has been done on other stations: walls had a new hydrophobic treatment and were covered with easily mounted lining instead of the previous plastering; the escalators were covered with shiny metal sheets for fire resistance and their standing lights that could potentially be vandalised were replaced with lines of light emitting diodes, which also saves electricity. The reopening of the station was accompanied with a Tchaikovsky music concert.^[4]

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  Lesnaya station building
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  The original underground green side wall tiling and station name reminding of forests
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  The underground hall
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  The Sun artwork light