桃園農田水利研究發展基金會

Plan Name

Survey on the Catchments Areas of Farm Ponds and Estimates of their Effective Storage in Taoyuan Main Canal Irrigation Area

計畫編號

86-2-03

類別

灌溉營運管理類

摘要

本計畫主要目標為貯水池集水面積之釐定及推估湖口工作站貯水池群有效蓄水量。貯水池集水面積之釐定係依現場地形實地勘查完成;貯水池有效蓄水量為推估因貯水池之興建而增加之水量，亦即各旬引入貯水池水量在灌溉後之剩餘水量，也就是經由貯水池運轉後可貯於貯水池之多餘水量稱之，利用1970年到1994年之降雨資料依GAMMA 統計分佈，以發生75%之平水年降雨量，做為降雨量之計算基準，有效雨量依現有方式推估，做模式模擬演算。模擬前調查發現湖口工作站實際灌溉情形與灌溉計畫不盡相同，因此，模式計算採用八十六年實際灌溉資料演算，有效蓄水量的計算方式為各貯水池之旬未蓄水量減去旬初蓄水量的差值。依據此定義，八十六年實際運轉有效蓄水量為54,334m3，採用(方式一)配水即各貯水池先依需水量配水，如有多餘水量，再按照貯水池容量大小配水，演算結果有效蓄水量為7,699千立方公尺，溢水量為7,474千立方公尺;另再按照(方式二)配水即貯水池旬初蓄水量與有效容量90%之差值大小比例配水，如有多餘水量再平均分配，演算結果有效蓄水量為13,315千立方公尺，溢水量7,735千立方公尺，其中以依各貯水池需水量86-2-3-1 本計畫主要目標為貯水池集水面積之釐定及推估湖口工作站貯水池群有效蓄水量。貯水池集水面積之釐定係依現場地形實地勘查完成;貯水池有效蓄水量為推估因貯水池之興建而增加之水量，亦即各旬引入貯水池水量在灌溉後之剩餘水量，也就是經由貯水池運轉後可貯於貯水池之多餘水量稱之，利用1970年到1994年之降雨資料依GAMMA 統計分佈，以發生75%之平水年降雨量，做為降雨量之計算基準，有效雨量依現有方式推估，做模式模擬演算。模擬前調查發現湖口工作站實際灌溉情形與灌溉計畫不盡相同，因此，模式計算採用八十六年實際灌溉資料演算，有效蓄水量的計算方式為各貯水池之旬未蓄水量減去旬初蓄水量的差值。依據此定義，八十六年實際運轉有效蓄水量為54,334m3，採用(方式一)配水即各貯水池先依需水量配水，如有多餘水量，再按照貯水池容量大小配水，演算結果有效蓄水量為7,699千m3，溢水量為7,474千m3;另再按照(方式二)配水即貯水池旬初蓄水量與有效容量90%之差值大小比例配水，如有多餘水量再平均分配，演算結果有效蓄水量為13,315千m3，溢水量7,735千m3，其中以依各貯水池需水量。

Abstract

The objectives of this Project are to estimate the catchment area and the effective storage of the farm ponds managed by the Fu-Kou Irrigation Working Station, Taoyan Irrigation Association. The catchment areas of those farm ponds were estimated by means of field investigation and field survey. As the availability of water collected to the pond is the function of effective rainfall, and the calculation of effective storage adopted the theory of water balance and flood routing during operation of the farm pond. In this connection, a simulation model was formulated for undertaking the task of calculation. The rainfall record in the catchment area from 1970 to 1994 was analyzed as the basic input of the model source. The result of analysis showed that the annual rainfall has the characteristic of GAMA probabilistic distribution. Thus the 75 % of return period of the GAMA distribution of annual rainfall was adopted as the basic effective rainfall in the above-mentioned simulation. Result of simulation are:(1)Water Released based on the planned irrigation: the result of simulation found the effective storage of those farm ponds to be 7,699,000 cubic meters; while the amount of water ineffectively spilled out in the same period is 7,474,000 cubic meters; and(2)Water released based on 90 per cent of planned water requirement in the initial water shortage period; the result of simulation found that the effective storage of those farm ponds is about 13,315,000 cubic meters, while the water spilled was estimated at 7,735,000 cubic meters.It was also found during simulation that, the actually water released for irrigation based on the availability and requirement of individual farm pond could result in a better water utilization with less amount of water spilled out.

計畫主持人

柯海生

Project Director

Hai-Sheng Ko

關鍵字

貯水池集水面積釐定、有效貯水量推估、桃園大圳灌區

Keywords

Farm Ponds、Estimates of Effective Storage、Taoyuan Main Canal

成果報告