China Development Bank (CDB) offered a 580 million yuan ($82.85 million) loan on Friday for the water quality improvement of the Taihu Lake in east China.

Friday's offer brings CDB's total loans for the same purpose to 6.4 billion yuan since 2002.

The new loan will be used in projects to improve water environment in areas near the Taihu Lake, the country's third largest freshwater lake, that will contribute to the clean-up of Taihu.

Nutrient runoffs and other pollutants caused blue-green algae bloom in Taihu last summer, that rendered tap water undrinkable for about 10 days for more than 1 million people in Wuxi city, Jiangsu Province.

The Chinese government has set a timetable for pollution control of the country's major lakes, aiming to curbing the pollution aggravation by 2010 and restoring them to their original state by 2030.

As one of the country's three policy banks, the CDB has provided more than 86.2 billion yuan in loans for pollution control and environmental protection projects by the end of this March.

The policy bank was recently approved by the State Council, the Cabinet, to undergo shareholding transformation and turn itself into a commercial bank. The total assets of CDB stood at 2.83 trillion yuan by the end of 2007.