Rainwater resource problems in Taiwan

Taipei city has abundant rainfall, with an average of approximately 2,000mm rainfall each year. However, because of uneven time and space distribution of rainfall, only with Feitsui Reservoir as the only water supply for Taipei city, it is easy to have water shortage in case of insufficient rainfall. Due to environmental protection and preparation concerns, advanced countries such as Europe, America and Japan use buildings or open areas to collect rainwater for reuse. In other words, “rainwater storage and reuse” has become a new method in sustainable use of water resource.

Rainwater recycle system

Process of “rainwater reuse” in the National Chiang Kai-shek Memorial Hall The rainwater storage and reuse system were funded by and the school campus improvement project at the Green department, conducting by Architecture and Building Research Institute, of Ministry of Interior. The engineering work was conducted in two phrases, respectively finished in 2003 and 2004. It was constructed to collect rainwater from main buildings of the National Chiang Kai-shek Memorial Hall, then direct to the collection tank through the sewage system. After a buffering/sedimentation/filtration process, direct to two 900 tones and 300 tones underground cement storage tanks located near the flower beds. After purification, the water is used for irrigation and replenishing pool water.

1.Collection: Collect rainwater on the roof

2.Temporary storage: Collection tank for initial storage

3.Water purification: Buffering, sedimentation, filtration

4.Storage: Underground rainwater storage tank

5.Usage: Irrigation

Introduction of the Rainwater Recycle system in the National Chiang Kai-shek Memorial Hall

The National Chiang Kai-shek Memorial Hall is located in Taipei City, with an area of 250,000 m2. As one of the most representative sights in our country, tourists worldwide come for visits. Furthermore, with an elegant and quiet environment, it is the perfect spot for recreation activities.

In order to construct a city ecological park for a high quality outdoor instruction, over three hundred species of plants and flowers were planted. With constant maintenance, flowers bloom throughout the year, attaining beautiful scenery. Each year, 25,000 tones of water is required for irrigation, approximately a year’s worth of water usage for 70 small families. If tap water and groundwater is used for irrigation, not only does it require huge funding, but also destroy the environmental ecology. Hence, it is essential to use rainwater as substitute water supply.