New policies and measures for saving a great manmade reservoir providing drinking water for 20 million people in the Republic of Korea.

Water quality of the Paldang reservoir, the largest drinking water supply source in the Republic Korea provides raw water for about 20 million people living in Seoul Metropolitan area. Water quality has been deteriorating mainly due to improperly treated livestock waste and domestic wastewater discharged from motels, restaurants, and private homes. A recent survey conducted by the Ministry of Environment (MOE) showed that the water quality of this reservoir has been identified as Class III must contain less than 6 ppm of BOD, which will require advanced purification treatment before it can be used as drinking water. The MOE also announced that this water source would no longer be potable unless wastewater in the catchment is treated efficiently. To protect drinking water resources, the MOE has set up comprehensive management. These programmes include new regulations, measures, land use planning and economic incentives.