The lake's drainage basin covers an area of 16,890 square kilometres (6,520 sq mi), of which 97% is in Russian territory. It has 4,000 to 4,400 km2 (1,500 to 1,700 sq mi) of water surface area. It is fed by 23 rivers (8 in China and 15 in Russia), but the only outflow of the lake is the Songacha River.
The lake's average depth is 4.5 metres (15 ft), while its maximum depth is 10.6 m (35 ft). Its average volume is 18.3 cubic kilometres (4.4 cu mi), though it can fill up to 22.6 km3 (5.4 cu mi). The lake belongs to the Ussuri River System, which is part of Amur River System. The maximum monthly mean temperature is 21.2 °C (70.2 °F) (July), while the minimum monthly mean temperature is −19.2 °C (−2.6 °F). Rainfall mainly occurs in summer, reaching 750 millimetres (30 in) annually.