Study for Improving an Duong Lake Water Quality for Chi Lang Nam Stork Island Conservation and Ecotourism Development

An Duong Lake has been selected for the study to its important role in storks’ and cauldrons’ habitat protection, fishery and ecotourism of Hai Duong Province and particularly Thanh Mien District. Qualitative and quantitative methods were used throughout the research. The overall purpose of this study is to find out some mitigating measures for improving water quality of An Duong Lake in order to conserve herein stork islands and ecotourism development. Specifically, the objectives of the study are included: (i) To identify An Duong Lake pollution sources; (ii) To assess An Duong Lake water quality; (iii) To suggest water pollution mitigating measures. The main sources of water pollution of An Duong Lake are: storks’ and cauldrons’ feces, domestic and livestock waste and run-off. Wastes of all these sources are discharged directly into the lake without any treatment. In dry and wet season, concentration of SS, BOD and COD of almost samples is higher than regulatory levels (Vietnam National Technical Regulation 08:2008/BTNMT, Class A2 and B1). pH of all water samples in the range of permissible level. Concentration of N-NH₄⁺ and N-NO₃^- is lower than permissible level. The pollution of An Duong Lake water is heavier in dry season than in wet season. Lakeshore water is more contaminated than the central part of lake. Several comprehensive methods for improving An Duong Lake water quality should be conducted such as Water hyacinth (Eichhornia crassipes) and Reed (Phragmites communis) growing for water pollutant mitigation, Septic tank toilet for treatment of domestic waste water; Treatment of livestock wastes; Combination of filtration with EM for mitigating pollutant in run-off; Fish farming; Pollution sources control and An Duong Lake water monitoring. Water hyacinth and reed growing is found out to be the most effective and practical method for mitigating An Duong Lake water contaminants.