Daegu has begun testing whether water from the middle Nakdong River can be naturally filtered through sand and gravel before it enters the drinking-water treatment process. A pilot plant at the Munsan Water Purification Plant in Dalseong is examining riverbed water and bank-filtered water as a possible way to lower pollution without moving the intake farther upstream.
The city plans to assess whether the approach can be applied in practice by September next year, but the evidence does not yet establish a final supply decision or water-quality outcome.