The Inya River basin is located in the northeastern Okhotsk region, where Khabarovskyi Krai borders Magadan and Yakutia. The river's origins are in the scenic mountain lakes of Asia's main watershed, in the area of the mouth of the Kolyma River. The Inya River valley runs north to south for a distance of about 300 km. The Kulinsky Ridge in the west and the Kheidzhansky mountain chain in the east separate the Inya River valley from the other rivers of the North Okhotsk area.
The population density of the watershed is very low, and natural systems are in close to pristine conditions. Large stocks of chum, pink salmon, coho, Dolly Varden char and rainbow smelt reproduce in the Inya basin. These are the highest spawning grounds of anadromous red salmon in all of Asia. The river is rich in grayling, a large East Siberian char. In mountain lakes there are two forms of living chars that are distinct from the Dolly Varden and East-Siberian char. Stocks of anadromous salmon are the main source of subsistence for the indigenous Even people who have lived here since ancient times.
The populations of most salmon species in the Inya River are in good condition. There is a trend to intensify both commercial and illegal fishing of chum and coho, which may compromise the condition of these species in the near future. The negative factor affecting salmon populations in the basin is excessive commercial fishing and poaching. The lower part of the Inya River is divided into several fishing zones. In the upper part of the river there are semi-legal fishing crews. It is a common violation of fishing rules here to exceed the allowed catch limit and take only caviar, because it is not profitable to transport the whole fish to the river mouth.