| 摘要: | Yang Ming Shan, located in northern Taiwan, has a very beautiful landscape which is a natural background for national park A reservoir would increase the beauty of the scenery in the hilly area. However, the primary use of the reservoir would be the flood control for the Taipei Basin.
This paper first discusses the topography of the area, for the topography has a great effect on the distribution of the rainfall. Chi Shin Shan, located in the North-East at 1,120 meters elevation, is the highest peak in this area. Two creeks, Tzu Ming Chi and Song Chi, originate from Chi Shin Shan and run to South-Wet They join at the foot of Sha Maw Shan, where the geological structure is favourable for building a reservoir and there are many trees and plants covering the soil to protect against erosion due to rainfall and runoff.
The rainfall and the evaporation are the two most important climatic factors effecting the water of reservoir. The mean annual rainfall is 4,274mm. That makes this, area one of the rainfall centers of Taiwan; and there is about 195 rainy days per year. The mean annual evaporation is 822 mm. This is due to the lower temperature and the higher humidity. Therefore, the water for the reservoir is abundant. Through September to November, the monthly rainfall is more than 550mm on account of the typhoon and the thunderstorm. But in April, it only rains an average of 183 mm. The ratio of maximum monthly rainfall with the minimum is about 3: 1; it shows that the distribution of the rainfall into whole year is more or less homogeneous and that the operation of the reservoir wil be favourable.
The reservcir was planned to be built at the foot of Sha Maw Shan with its dam about 100 meters high and 600 meters long. Its water, capacity would be about 24, 400, 000 cubre meters.
The conclusions of this paper will give some useful hints, and valuable tabulations and figures for making a detailed and complete design of the reservoir. |
