Water pollution by Pangasius production in the Mekong Delta, Vietnam: causes and options for control

Abstract

In this paper, we analyse water pollution caused by farming and processing Pangasianodon hypophthalmus in the Mekong Delta of Vietnam. The results show that 1tonne of frozen ¢llets releases 740 kg BOD, 1020 kg COD, 2050 kg TSS, 106 kg nitrogen and 27 kg phosphorus, of which wastewater from ¢sh ponds contributes 60^90% and sludge from ¢sh ponds and wastewater fromprocessing facilities contributes 3^27% of the total emissions. Overall, the combined waste emissions from Pangasius production and processing account for o1% of the total TSS, nitrogen and phosphorus loads in the Mekong Delta. Despite the relatively low contribution towater pollution, further reductions are possible through more e⁄cient use of inputs and low-cost treatment and re-use of e¥uent streams.The use of cleaner production technologies and the development of wastewater treatment plants could be applied to large farms and processing facilities to reduce water pollution in Pangasius processing. Low-cost options for small-scale farms include the optimization of the discharge design for the re-use of wastewater.