BEIJING - An environment official on Tuesday sounded the alarm of pollution in China's rivers, lakes and seas, saying the problem in the near-shore water of major coastal economic zones is particularly serious.

Vice Minister of Environmental Protection Wu Xiaoqing said the quality of the near-shore water of north China's Bohai Sea and the East China Sea as well as water in five of the nine bays along China's coast was "extremely poor."

Wu told a press conference that the five bays include Bohai Bay, the Yangtze estuary, Hangzhou Bay in Zhejiang Province, the Minjiang estuary in Fujian Province and the Pearl river estuary in southern province of Guangdong.

Wu said that among 469 stations to monitor water quality along 10 major river basins, including that of the Yangtze River, the Yellow River and the Pearl River, 61 percent reported the rating between the first and third grade last year, which means the water could be used in water source, natural reserves and drinking water.

Meanwhile, 25.3 percent of rivers were polluted and rated as the fourth or the fifth grade, meaning that the water could not be immediately contact by people.

The water quality of 13.7 percent of rivers were even below the fifth grade, which denotes that the water could only be used in agriculture, Wu said.

Wu also said that in 26 major lakes and reservoirs under state environmental monitoring, 53.8 percent were affected by eutrophication, or the process in which bodies of water receive excess nutrients that spur excessive plant growth, including 7.7 percent facing moderate eutrophication and 46.1 percent facing slight eutrophication.

Among 4,727 groundwater monitoring sites in 200 cities, the water quality of 45 percent has been excellent, good or relatively good, but that of the other 55 percent has been poor or very poor, the official said.