Bratsk was founded by Russian settlers in 1631 as a fortress. Several wooden towers from the 17th-century fort are now exhibited in Kolomenskoye Estate of Moscow. Bratsk was among the Blacksmith Institute's "Dirty Thirty", the thirty most polluted places in the world.
Until recently, the Bratsk Reservoir - one of the world's largest - was a source of drinking water for many nearby cities. Last year, after tons of mercury were found at the bottom of the reservoir, warnings were posted urging local citizens to avoid the reservoir at all costs. However, owing to Russia's economic troubles, the reservoir still remains a source of fish and other food products for many hard-pressed local residents. According to Yuri Udodov, head of the Federal Committee on Ecology (FCE) in the state of Irkutsk, this region has "the highest rate of discharge of metallic mercury into the environment [in] all of Siberia. The extent of mercury pollution in the ground around the nearby Usolye chemical plant is equal to half the total global production of mercury in 1992.
Bratsk has been declared an ecological disaster zone. The Bratsk Aluminium Plant has been polluting its surroundings to such great degree that the town of Chikanovskiy was evacuated in 2001 due to repeated health emergencies.