White Sea–Baltic Canal had plans to carry 800,000 tonnes of fuel oil over the canal during 2003, and to increase the volume to in 2004. The fuel was transferred from Volgotanker river tankers to Latvian seagoing tankers at a floating transfer station near the Osinki Island in the Onega Bay of the White Sea, north-east of the port of Onega. Transfer operations began on 24 June 2003. But on 1 September 2003 a low-speed collision between Volgotanker's "Nefterudovoz-57M" and the Latvian "Zoja-I" during a transfer caused a crack in the "Nefterudovoz's" hull, with a subsequent oil spillage. Various estimates of the extent of
Onezhsky District Porog; there is regular passenger navigation. There is also limited passenger service on the Onega Bay. Onega is served by the Onega Airport which has weekly passenger flights to Arkhangelsk and to the "selo" of Purnema on the Onega Peninsula. Onezhsky District has a very high concentration of historical, archaeological, and architectural monuments. The district contains thirty-two objects classified as cultural and historical heritage by Russian Federal law, and additionally eighteen objects classified as cultural and historical heritage of local importance. Most of these are wooden churches and chapels. The monuments classified as historical and architectural heritage are the following: