A fish started passing up the world's highest fish ladder at Zam Hydropower Station, Tibet's largest, on Thursday.

Zam Hydropower Station on the Yarlung Zangbo River, became fully operational on Tuesday and is expected to produce 2.5 billion kilowatt-hours of electricity a year.

The fishway -- 3.6 km long and rising 67 meters at a cost of 200 million yuan (about 32 million U.S.dollars) -- was planned from the very beginning to reduce the station's effect on the local environment, said Hu Shifan, assistant to the head of the station.

On Thursday, 53,000 fish fry were released into the river, with plans to release 100,000 endangered fish annually.

                                                                                                                                    Editor: Lily Li