BEIJING -- China's water quality improved in the first three quarters this year, partly due to the implementation of an action plan for combating water pollution in 2015, an official said Friday.

In the first three quarters, 70.3 percent of 1,922 monitored surface water areas around the country could be used directly as drinking water, up 4 percentage points from a year ago, Zhao Yingmin, vice minister of environmental protection, said at a press conference.

During the same period, 8.6 percent of them received the lowest rating for very poor quality, often called "black and stinky" water, down from 9.8 percent for the same period of 2015, Zhao said.h Zhao attributed the progress mainly to the strict implementation of the Action Plan for Water Pollution Prevention and Control, unveiled in April 2015 by the State Council to reduce pollutants, improve drinking water and promote water conservation.

Targets for improvements by the end of 2020 include reducing the amount of severely polluted water and containing groundwater contamination.

Specifically, the plan said more than 70 percent of the water in the seven major river valleys, including the Yangtze and Yellow rivers, should be in good condition by 2020.

On Tuesday, a State Council executive meeting presided over by Premier Li Keqiang approved a new guideline for environmental protection for 2016-2020, with concrete targets for reducing air, water and land pollution.

Zhao said the ministry will prioritize drinking water safety in the next few years, with main focuses on protecting unpolluted water and improving the lowest quality water.