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
Arkhangelsk Oblast of the Northern Dvina and the Onega. The railroad construction gave the momentum to the population and exploitation of these areas. A branch from Konosha eastwards to Kotlas and further to Vorkuta was constructed in the 1940s to facilitate the transport of coal from the Komi Republic. From Kotlas, another branch continues south to Kirov. A branch from Obozersky to the west, to Onega and further to Belomorsk, was built during World War II to secure the transport of goods from the harbour of Murmansk to central Russia. A piece of railroad between Arkhangelsk and Karpogory was also built in