Willow River is a river that can breathe, and the retaining wall of both sides have been broadened as the revetment slope, which can help the drainage and waterproof. Consideration to water quality and ecological balance by infiltration and evaporation was put to the design, so the serious pollution of water of willow river can be changed to mild pollution after purifying the water of willow river; The replant of trees of and the new water willow on the river bank preserve the original beauty. The tassels, Taiwan Koelreuteria elegans, Fraxinus formosana and other Taiwanese native plants make the Willow River show various views throughout the year.