Baikal

Frequently Asked Question

The Angara river

How much water does the Angara river carry out of Baikal per year?

On average - about 60 cubic km.

What is maximum breadth and depth of the Angara river at its source?

Its breadth is about 1 km. Maximum depth - 4-6 m. The cliff "Shaman Stone" is never covered by water in the middle of the river bed at the source.

What is the velocity of the river current at the source?

Along the river fairway from 4 to 8 km/hr (1-2 m/s). At a high level of Baikal the velocity used to be greater.

What is the difference between the height above sea level at the Angara source and that in its mouth?

The Angara source is located at the Baikal level, that is, at an altitude of 456 m above sea level, at the point of confluence into Yenisei at an altitude of 76 m above sea level, i.e. the difference is 380 m.

What about the rivers Angara and Yenisei? - Does the Angara river flow into the Yenisei or the Yenisei flows into the Angara?

The Angara river at the point of confluence into the Yenisei carries 120 cubic km of water per year, and the Yenisei only 100 cubic km by the Angara mouth. But geomorphologically and historically the Yenisei is a principal river, and the Angara is only one of its largest tributaries.

How did hydropower station dams affect the Angara water quality?

The river Angara, its fauna, the main part of which contained endemic baikalian species, have dramatically changed. The major factors are: sharp retarding of the current and pollution, coming from industrial centres - Irkutsk, Angarsk, Usolye- Sibirsk, Bratsk, Ust-Ilimsk - where different industries are developed, including the paper and pulp industry, which is poisoning greatly the Angara waters. The Angara fauna has become much poorer, since many baikalian endemics were replaced by some species widely spread in eutrophic lakes. In the water thickness of the reservoir there occurred much zooplankton, primarily Daphnia, phytoplankton biomass considerably increased, there appeared "in mass" blue-green algae. Water quality continued to be degraded.

How did the construction of dams affect fish in the Angara reservoirs?

Instead of river species - inhabitants of pure rivers - reservoirs become dominated by species typical of lakes - roach, perch, pike. To improve fishery in the Bratsk reservoir baikalian omul and bream were introduced there.

Which of the Angara reservoirs is most pure?

As is shown by studies of the Scientific-Research Institute of Biology of Irkutsk State University, among the reservoirs on the Angara - Irkutsk, Bratsk, Ust-Ilimsk - most pure is the Irkutsk Reservoir, starting by Lake Baikal, at the Angara source. Heavily polluted is the Ust-Ilimsk Reservoir, where poisoning substances coming into the river are accumulated. Waste waters from the Bratsk Timber Industry Complex, coming into the river Vikhorevaya, which flows into the Ust-Ilimsk Reservoir, are doing irreparable damage to the quality of its water.