LANZHOU, Aug. 20 (Xinhua) -- A top-level emergency response for flood control and natural disaster relief was activated late Wednesday in Zhouqu County of northwest China's Gansu Province as torrential rain has triggered severe floods and is forecast to continue.

Four rounds of downpours since Aug. 6 have taken a heavy toll on Zhouqu County of Gannan Tibetan Autonomous Prefecture, leading to direct economic losses of 595 million yuan (about 85.9 million U.S. dollars).

In the worst-hit Qugaona Township, which has seen 170 to 180 mm of rainfall, roads were damaged, electricity and communication were cut off and more than 2,500 people were urgently evacuated.

Gansu Province on Tuesday upgraded the emergency response level for natural disaster relief to Level III, the third-highest in the four-tier emergency response system.

Zhouqu is prone to frequent landslides and mudslides. The county has strengthened the construction of a geological disaster early warning system, which has been monitoring 173 potential geological disaster points over the past decade.