Unusually high temperatures and a prolonged drought are affecting large swaths of China, reducing crop yields and drinking water supplies.
The lack of rain has been especially marked in the southwestern megacity of Chongqing, which encompasses a large area of mountains and rivers.
State media on Tuesday reported fire trucks were delivering water to outlying villages for drinking and irrigating crops.
Rainfall in Chongqing has been half of what is usually expected for the year and some smaller waterways have dried up entirely.
Authorities have issued warnings of temperatures exceeding 40 Celsius (104 Fahrenheit). Many parts of China have broken records for high temperatures this year.
Amid the drought, other areas of China have been hit by flash floods, underscoring the effects of climate change on the vast nation of 1.4 billion people stretching from the mountains and deserts of Central Asia to the South China Sea.
The Chongqing drought has affected more than 600,000 people and 36,700 hectares (90,690 acres) of crops, the Xinhua News Agency reported.
Neighboring Hubei province has also been badly hit, with some areas reporting the growing season a complete failure, Xinhua said.