台北盆地下水可再利用量評估

Assessment the Reusing Amount of Groundwater for Taipei Basin

陳忠偉(Jung-Wei Chen) ； 謝壎煌(Hsun-Huang Hsieh) ； 李振誥(Cheng-Haw Lee)

《農業工程學報》 54卷1期 (2008/03) Pp. 70-84

https://doi.org/10.29974/JTAE.200803.0007

摘要

由於全球氣候變遷導致台灣氣候呈現不穩定狀態，2002年台灣發生罕見之乾旱年，故僅靠地面水供應用水已不敷使用，而台北地區之分配用水更是捉襟見肘，因此適時適量之抽用地下水，不但能減輕地面水有限之水資源需求，更能達到地面水與地下水聯合運用之水環境永續經營目標。
本研究目的爲評估台北盆地之地下水可再利用水量，由台北盆地之水文地質資料建構地下水流數值模型，以盆地內地下水位監測資料校正數值模式，使數值模式符全台北盆地含水層物理機制，利用零水位變動法與希爾法推估台北盆地地下水之合適出水量與水位，並列爲管理調配方案之限制條件。本研究根據合適出水量與水位限制值、開發區域與乾旱時期水源需求等條件，進行地下水可再利用量與對於地下水環境影響進行評估。
由研究成果顯示，以合適出水量與水位爲限制條件，台北盆地地下水可再利用量每年約爲58.69~80.83×10^6立方公尺。若地下水位限制僅針對基隆河、新店溪與大漢溪等七個分區進行開發，評估其地下水可再利用水量每年紡爲15.66~27.82×10^6立方公尺，且其最大水位洩降約0.17 m，對地下水位影響民生與工業用水，初始之農業用水大都位於大漢溪流域，若於乾旱期間將農業用水提旱撥爲民生與工業用水，初始之農業用水需求則可由樹林鎮與土城市之地下水支援每年約5.54~7.61×10^6立方公尺。

關鍵字

地表與地下水聯中運用 ； 合適出水量 ； 合適水位 ； 乾旱時期

並列摘要

Due to the changes of the global climate, it causes the weather in Taiwan become unstable. In 2002, the weather was very droughty, causing the surface water become insufficient for Taipei area. However, if the groundwater can be suitability used, it can not only reduce the need of surface water, but can also jointly use the surface water and groundwater to reach the objective of sustainable operation of water environment.
This objective of this research is to evaluate the reusing water amount of the groundwater in Taipei basin. Initially, the numerical model of groundwater flow was constructed based on the hydrogeologic dada of Taipei basin. Secondly, the monitoring data of groundwater level was adopted to correct the above numerical model in order to accord the numerical model with the physics mechanism of aquifer in Taipei basin. Both the zero groundwater change method and Hill method were used to evaluate the suitability yield and suitability groundwater level. In this study, the conditions of suitablility yield and suitability groundwater level. In this study, the conditions of suitability yield, suitability groundwater level, exploitation area and the need for water in droughty period were considered to evaluate the reusing amount and environmental influence of groundwater.
The research results showed that, under the restricted condition of suitability yield and suitability groundwater level, the reusing amount of groundwater is about 58.69~80.83×10^6m^3 per year. However, if the restricted condition is only for Keelung River, Sindian River and Dahan River, the reusing amount of groundwater is about 15.66~27.82×10^6m^3 per year, Also, the maximum drawdown of groundwater level was evaluated to be 0.17 m, which has only a minor influence to groundwater level. Moreover, if we considered that the agricultural water was located at the Dahan River basin, the agricultural water can be transformed to be the civil and industrial water. The original agricultural water can be supply by the groundwater of Shulin town and Tucheng city, which is about 5.54~7.61×10^6m^3 pear year.

並列關鍵字

Jointly use the surface water and groundwater ； Suitability yield ； Suitability groundwater level ； Droughty period