圖書典藏及影音數位平台

基於水資源之永續利用及考量原有各水權人權益，同時兼顧河川生態環境，水權量之核發除自需求面考量，依據水利法第17條規定應以其「事業所必需者」為限外，於供給面方面，亦須依據水利法第21條規定根據水文測驗結果，考量區域內水源之水量水源在一定時期內之通常保持之水量，仍足以供給申請人事業所必需者始能核給地面水水權。原水利法施行細則(58年8月5日修正頒布)第67條水源「通常保持之水量」規定為「逐年平均量」，93年水利法施行細則修正後，細則第15條第2項將地面水「通常保持之水量」修正為「流量超越機率百分之八十五之水量」。另水權登記審查作業要點第4點明訂水權水量核准之各項條件，即主管機關審核水權之引用水量時，應參酌引水地點之各月水文狀況、其上、下游已核准水權水量、環保基流量及事業所需用水量覈實核給。為落實上開水利法規定，並建立科學化之供給面水量審核參考基準，本署（前經濟部水資源局）於85至87年委辦「台灣地區各水系水源任一斷面潛能水量分析」計畫，以降雨—逕流模式建構各流量站河川流量之超越機率分布，並以克利金區域統計分析方法推估未設水文站位置之流量超越機率分布。經濟部水利署於93年參酌前述計畫成果，建置完成網路版「地面水潛能水量計算系統」，據以參考核發水權。

This project establishes a new Surface Water Availability Calculation System which is based on ESRI’s ArcGIS software. This system provide surface water availability determinations for water right examiners having an identical judgement when they review an application. The computer simulation models are validated and applied in Daan River for the last two years. This year the models applied to the other 10 rivers, including Touqian River, Zhonggang River, Houlong River, Dajia River, Wu River, Zhuoshui River, Beigang River, Puzi River, Bazhang River and Beinan River. Next year, will applied to the other 15 main rivers in Taiwan and applied to minor rivers in 2014. Before estimating flow characteristics at ungauged sites, this project identified 194 gauging stations in Taiwan to 7 types by the homogeneous regions method consists of two complicated statistical techniques (principal component analysis and cluster analysis), which are Tamsui River region, Lanyang region, Hualian-Taidung region, Fengshan River to Houlong River region, Daan River and Dajia River region, Wu River to Jishui River region and the region south of Zengwen River. This project reviews the runoff coefficient and rainfall-runoff hydrograph diagram for selecting proper record to convert a Kriging Model. Flow record are revised by withdrawal record to simulate natural flow. Kriging Model are used to estimate flow at ungauged sites. Water availability are determinated by the estimated flow and the water right simulation model. The major part of the water right simulation model is to establish a method of streaming and coding of stream network to show variable stream and surface-water withdrawal locations by a simplified topological diagram and to specify the relationship among control points for estimating surface-water availability. The upstream contributing area and downstream influence area could be obtained by tracking the reach streaming which is established using a relation table of polylines and nodes.