Aerial photo taken on June 2, 2018 shows the exposed riverbed of Songhua River in Harbin, northeast China's Heilongjiang Province. The water level of Harbin section of Songhua River reduced to 113.55 meters, the lowest for some 11 years, on May 29. (Xinhua/Wang Kai)

People collect clam on the exposed riverbed of Songhua River in Harbin, northeast China's Heilongjiang Province, June 2, 2018. The water level of Harbin section of Songhua River reduced to 113.55 meters, the lowest for some 11 years, on May 29. (Xinhua/Wang Kai)

Aerial photo taken on June 2, 2018 shows the exposed riverbed of Songhua River in Harbin, northeast China's Heilongjiang Province. The water level of Harbin section of Songhua River reduced to 113.55 meters, the lowest for some 11 years, on May 29. (Xinhua/Wang Kai)

Aerial photo taken on June 2, 2018 shows the exposed riverbed of Songhua River in Harbin, northeast China's Heilongjiang Province. The water level of Harbin section of Songhua River reduced to 113.55 meters, the lowest for some 11 years, on May 29. (Xinhua/Wang Kai)

Aerial photo taken on June 2, 2018 shows the exposed riverbed of Songhua River in Harbin, northeast China's Heilongjiang Province. The water level of Harbin section of Songhua River reduced to 113.55 meters, the lowest for some 11 years, on May 29. (Xinhua/Wang Kai)

Aerial photo taken on June 2, 2018 shows the dry riverbed of Songhua River in Harbin, northeast China's Heilongjiang Province. The water level of Harbin section of Songhua River reduced to 113.55 meters, the lowest for some 11 years, on May 29. (Xinhua/Wang Kai)

Aerial photo taken on June 2, 2018 shows the dry riverbed of Songhua River in Harbin, northeast China's Heilongjiang Province. The water level of Harbin section of Songhua River reduced to 113.55 meters, the lowest for some 11 years, on May 29. (Xinhua/Wang Kai)