Lake Onega water per year, of which 46% are industrial and household water, 25% is stormwater runoff and 16% is melioration-related drainage. This drainage contains of phosphorus and of nitrogen; respectively of these elements are removed through the River Svir whereas the rest accumulates in the lake. Ships and motor boats (about 8,000 units) bring oil pollution at the level of about per navigation year, as well as phenols (), lead () and oxides of sulfur, nitrogen, and carbon. The lake basin is a major source of granite, marble and black schist in Russia which have been exploited in the area since
Republic of Karelia of high-quality fresh water. Lake Ladoga (Finnish: "Laatokka") and Lake Onega ("Ääninen") are the largest lakes in Europe. Other lakes include: The lakes Ladoga and Onega are located in the south of the republic. White Sea coast: In Lake Onega: In Lake Ladoga: The majority of the republic's territory (148,000 km², or 85%) is composed of state forest stock. The total growing stock of timber resources in the forests of all categories and ages is 807 million m³. The mature and over-mature tree stock amounts to 411.8 million m³, of which 375.2 million m³ is coniferous. Fifty useful minerals are