Lake Onega is relatively cold, with temperatures below for half of the year and average summer temperatures of about . The catchment area of drains into the lake via 58 rivers and more than 110 tributaries, including the Shuya, Suna, Vodla, Vytegra and Andoma. The only outgoing River Svir, which marks the southern boundary of Karelia, runs from the southwestern shore of Lake Onega to Lake Ladoga and continues as the Neva River to the Gulf of Finland. The White Sea–Baltic Canal runs through the lake from the White Sea to the Baltic Sea. The Volga–Baltic Waterway connects Onega Lake with the
Port of Arkhangelsk m total usable area for warehousing - 292,000 m², including closed storage - 40,000 m², open tarmac - 250 000 m². Customs warehouses 2000m ². In Arkhangelsk port is the only container terminal in the North, including the open space area of 98,000 m², which can contain 5762 TEUs at the same time, including up to 200 reefer containers and 2,200 containers with dangerous goods. Bandwidth container terminal 75000 TEUs per year. Port of Arkhangelsk Port of Arkhangelsk () is a major seaport at Arkhangelsk, located at the mouth of the Northern Dvina River, 50 km from the Dvina Bay