|Project Rationale and Linkage to Country/Regional Strategy
Chao Lake is the fifth largest freshwater lake in the PRC. Its catchment occupies about 10% of the total area of the Anhui province. The lake is important to industrial and agricultural water supply, water transport, tourism, and recreation in Anhui province. Over the last 20 years, the water environment of Chao Lake has been deteriorating due to the adverse environmental effects of rapid economic growth and urban development. During the 2000-2009 period, the urban population in the catchment increased by 30% and gross domestic product increased by 500%.
In 1996, Chao Lake was identified as one of the top three priority lakes in the PRC for environmental rehabilitation due to its poor water quality. Since then, the provincial and concerned local governments, supported by the national government and ADB, have provided large amount of resources to control municipal and industrial pollution in the lake catchment. These investments have reduced industrial and municipal wastewater to a certain extent, but they have not addressed all dimensions of the water quality problem in the lake. The lake continues to receive excessive concentrations of organic matter, nitrogen (N), and phosphorous (P). Particularly during summer times, elevated levels of pollutants and high temperatures result in algal blooms, depletion of oxygen in the water, and the emission of offensive odors.
The present average water quality in the lake is Class IV under the PRC's national environmental water quality standard and 50% of the water monitoring points in the lake are still Class V. This represents a slight improvement over the situation in 2005 when overall water quality in the lake was class V+, but is still far from the government's long term objective of Class III for the lake.
As a result of past investments and regulatory efforts, industrial pollution control in the lake catchment has improved. The two main pollution sources yet to be fully controlled are municipal point sources and non-point source (NPS) emissions. The Anhui Environmental Protection Department estimates that municipal sources account for about 50% of existing organic emissions into the lake, 57% of emissions of N, and 54% of P. Rural NPS emissions are estimated to account for 42% of organic emissions, 38% of N, and 42% of P.
The Anhui Provincial Government understands that a comprehensive approach is required to solve water quality problems in Chao Lake. To support the comprehensive approach, the APG has formulated the Chao Lake Environmental Rehabilitation Master Plan (master plan, 2008-2020), which suggests the need for about CNY50 billion of investments to develop a wide range of structural and non-structural measures, such as strengthened institutional mechanism, expanded and upgraded municipal wastewater treatment plants (WWTPs), extension of sewerage networks, continuation of the industrial wastewater treatment control program, comprehensive rural NPS pollution control, control of other NPS pollution sources through in-stream measures, water conservation, strengthened regulatory supervision, applied research, and public education.
The project supports the PRC's sustainable development agenda for the establishment of an environmental-friendly, resource-efficient, and harmonious society, as outlined in the PRC's 12th Five-Year Plan 2011-2015. The project will support the master plan and the PRC's 12th Five-Year Plan for Chao Lake environmental protection, and introduce an integrated approach to overcoming current constraints on the lake environment restoration. The project is aligned with the PRC country partnership strategy, 2011'2015, in supporting environmental sustainability and inclusive growth.