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
Onega stepanovi placed in phylum Proarticulata, as the segments in recently discovered, exceptionally well-preserved fossils display the glide, or "staggered", symmetry characteristic of the majority of proarticulatans. Imprints of "Onega stepanovi" have been found in the Verkhovka and Zimnie Gory Formations of the Ediacaran (Vendian) rocks of the Arkhangelsk Region, Russia. All the fossil specimens are negative imprints on the bases of fine-grained sandstone beds with the "elephant skin" and tubercle texture diagnostic of microbial mats. The same bedding planes contain various other Ediacaran species: "Cyclomedusa", "Ediacaria", palaeopascichnids, "Eoporpita", "Yorgia", "Andiva", "Archaeaspinus", "Vendia", "Dickinsonia", "Anfesta", "Albumares", "Tribrachidium", "Kimberella", "Parvancorina", "Charniodiscus" and others.