Acid rain, haze and noise are considered as three main threats to the environment of Zhejiang province, according to a report released by Zhejiang Environmental Protection Bureau on Tuesday.

The report, which evaluated the environmental conditions of the province in 2012, said that Zhejiang's environment has improved.

Last year, 86.7 percent of Zhejiang's drinking water reached the qualified standard, and 98.6 percent of air quality was qualified.

However, there are still problems threatening the province's environment.

Acid rain accounted for 84.1 percent of Zhejiang's total rain last year, a 1.3 percent increase year-on-year. Haze occurred on 77.5 days last year, while in Hangzhou, Jiaxing and Huzhou, the number was 168. Noise is another problem.

The province is determined to control air pollution by promoting its public bicycle system throughout the province and upgrading gasoline standards.