Lake Onega Reservoir has an area of and volume of , i.e. almost the same as those of Onega Lake. Its construction raised the water level of the lake by . The lake contains a well-developed navigation system which is part of the Volga–Baltic Waterway and White Sea – Baltic Canal, connecting the basins of Baltic, Caspian and the northern seas. These canals allow water transport of goods from the lake to the countries from Germany to Iran; most traffic goes to Finland, Sweden, Germany and Denmark. The Onega Canal running along the southern shore of the lake there is not used
Port of Murmansk Arkhangelsk and St. Petersburg (later renamed Petrograd). However, after the blocking of the Ottoman Empire's straits of the Bosphorus and Dardanelles to outside shipping and blockading of the Baltic Sea port of St. Petersburg, the Russian Empire could only use the northern port of Arkhangelsk. This port had limitations: when winter presented itself, navigation and shipping of any sort came to a halt. Therefore, it was decided to build a new port. The chosen location was in Murmansk due to its ability to accommodate sea traffic year-round, proximity to existing communities and relative ease to connect it to the empire's