A water rise and possible underflooding of series enterprises is expected in St. Petersburg on December 21. Rescuers have announced that level of water at water gauge post "Obukhov plant" will reach dangerous 3-meter mark - it will lead to underflooding of enterprises at riverside of Nevsky district. Such water rise is due to ice dams. At present moment similar phenomenon is observed in Kolpinsky district of Leningradskaya oblast, where water rise in Ust-Ijor has reached 50 cm. As a reminder, Petersburg authorities plan to protect the town from frequent floods with new dam. First stage of its construction will be finished by 2008. New passes will be built at second stage of construction, which is due to 2011. Precise list of works will be approved by mid-2006. Necessary amount of second stage financing is 15 milliards rubles, but only 11.5 milliards are approved by Russian government yet. Decision about protecting structures erection was made in 1979. But construction started only in 2001. The total cost of project, excluding expenses on taxes and investments, will amount to $484 millions.