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1. What flood mitigation project has the most water gates??
2. What is a fishway?
3. When is Taiwan’s Flood Period?

What flood mitigation project has the most water gates?

Taipei Flood Mitigation Project. During torrential rains, when the water stage inside the dike (land) is higher than that outside the dike (river channel), the gates are opened and flood water is discharged into the river channel by gravity. And when the river level is higher than the water stage inside the dike, the gates are closed and the flood water is pumped into the river channel to prevent further flooding. With 33 water gates, the Taipei Flood Mitigation Project has the most water gates of all flood control project.

What is a fishway?

A fishway is a channel for the fish to crawl on. Taiwan has quite a few migration fishes like salmon. If a reservoir or dam is built and no fishway is set up, the fish cannot migrate back to the upstream river to spawn and the ecology is affected. The Water Resources Agency pays much attention to this ecologic issue. So far, fishways of 110 meters and 35 meters have been set up at Chi-Chi Weir of Jhuoshuei Riverand Gaoping River Weir for the fish to migrate home.

When is Taiwan’s Flood Period?

Taiwan’s flood period spans from May to the end of November each year. These seven months are Taiwan’s plum rains and typhoon seasons with the most rainfall. Plum rains mainly come from the cloud and rain system above the Yangtze River basin, while typhoons are mainly caused by the atmosphere depression of the Pacific Ocean. They both bring continuous torrential rains which can cause floods. To mitigate floods, in the past years the Water Resource Agency has executed flood-related projects on rivers for more than 2,000km, coastal protection measures for 500km, and local drainage improvement for more than 3000km.