Dagou River Ecological Water Management Park Introduction
The Dagou Stream, located at the bottom of Dahu Mountain Villa Street in Neihu District, is a natural creek that flows down from Baishi Lake Mountain, which is at an elevation of 485 meters. The upstream section features secondary forest on both banks, while the downstream segment flows through the Yuanchue Waterfall into a residential drainage system and eventually integrates into Dahu Park through the box culvert under Dahu Mountain Villa Street. The entire watershed is approximately 3,500 meters long with a catchment area of 340 hectares. To balance safety and conservation, the improvement of Dagou Stream in Neihu District has adopted a porous, near-natural construction method that provides habitats for flora and fauna. This has resulted in the flourishing of rich ecological resources. According to a survey by the Geotechnical Engineering Office, various species such as the Taiwan Blue Magpie, the Microhylid Frog, the Chinese Tree Frog, the Taiwan Black Butterfly, the Purple Butterfly, the Jade Butterfly, the Radu Frog, the Little Egret, the Rainbow Bird, and the Yellow-spotted Cricket have all been identified, making it an excellent outdoor ecological classroom. The downstream area of Dagou Stream was originally an agricultural zone but has been redeveloped into the Dahu Mountain Villa residential community due to urban development. To meet road demands, the creek was replaced with a drainage box culvert. In the past, heavy rains often overwhelmed the drainage system, leading to erosion and soil washouts. Significant disasters occurred, such as during Typhoon Winnie in August 1997. The Dagou Stream, located upstream in the Dahu Mountain Villa community, has been improved with stone masonry revetments that provide porous spaces beneficial for organisms while also reducing erosion. Additionally, a water-friendly pathway has been created along the streambed to meet the recreational needs of the residents, offering a pleasant natural environment. To create a natural ecological environment, the improvement of Dagou Stream utilizes fish ladders (drop structures) and bed stabilization to reduce the drop in riverbed elevation, slow down the flow rate, and diminish erosion energy. The constructed shallow areas also help to store water and create habitats for fish, shrimp, aquatic plants, and other organisms, thus maintaining the stream's ecology. Moreover, facilities such as water-friendly platforms and pathways have been installed in the wider sections of the watershed, allowing local residents and visiting tourists to enjoy interaction with the water. (Source: Taipei City Government, Public Works Department, Geotechnical Engineering Office)
