Water from the Guanting reservoir, Beijing's fourth largest drinking source, was not fit for human consumption or irrigation during the month of October, the Chinese capital's environmental protection agency reported in its latest monthly water quality report.

Water from the reservoir did not meet the number five standard, the lowest on China's five-tiered pollution monitoring scale, the report noted.

The water quality at another reservoir was found suitable only for irrigation. Four other reservoirs had dried up. In a separate report on Beijing lakes, the agency said that seven out of 16 lakes in the city were so polluted that their water could not be used to irrigate the parks that surrounded them.

The water quality in the lake at Yuanmingyuan Park and at Taoranting Lake, two major tourist spots, were unsuitable for drinking or irrigation. Only four of the city's lakes could be used to supply drinking water, while water from the other lakes was only fit for industrial use, the report noted. Earlier, the environment protection agency had blamed untreated wastewater, industrial effluents and agricultural pollution for the detoriorating water quality in Beijing's lakes and reservoirs.