Algal bloom in a reservoir in central China's Hubei Province has affected the drinking water of 15,000 people, local authorities said Saturday.
Algal bloom is a rapid increase in the population of algae in a water system.
Algae have grown quickly because of hot and humid weather in the Shiziling reservoir, the major safe water source in Wen'an County in Zhijiang city, making the water green and smelly.
Environmental protection and health authorities found excessive ammonia, nitrogen and phosphor levels in the water, but they didn't disclose the extent of algal bloom.
The water company has cut off supplies and local residents have been warned not to drink tap water. Instead they have to rely on bottled water.
The county's local government has mobilized people to dig for underground water to drink and also plans to divert water from nearby Lugang reservoir.