In 1597, Guo led locals to turn the waterway, which was about 200 meters, into three bends running up to 1.7 kilometers. Thanks to the newly added bends, water flowed much more gently here and water level increased, making it much easier for water transportation.
However, Sanwan was once heavily polluted by agrochemical and pharmaceutical factories in this area.
To revive the beauty of the Grand Canal, the Yangzhou government started treating pollution and restoring ecology in 2014. Combined efforts including relocating factories, dredging river channels, and planting aquatic plants, paid off. In 2018, the Sanwan Scenic Area was rated as a national AAAA-level tourist attraction.