濁水溪流域地下水資源開發與管理

Groundwater Exploitation and Management in Jhuoshuei River Watershed

王士榮(SHIH-JUNG WANG)

《台灣水利》 67卷1期 (2019/03) Pp. 43-67

摘要

彰雲地區的水資源開發，地面水的湖山水庫已開始蓄水，而鳥嘴潭人工湖亦通過審查準備興建，但兩工程完全供水後，仍無法滿足彰雲地區未來的用水需求，勢必仍須尋求其他水源。在無其他水資源可支援情況下，地下水資源仍將會是優先考量。名竹盆地位於集集攔河堰下游與濁水溪沖積扇頂的隘口之間，現代沖積層厚度約30公尺，具有良好蓄水特性，且為一天然獨立之地下水庫系統。近濁水溪河道的現代沖積層為取用伏流水與地下水的理想地點，可配合集集攔河堰操作，直接取到乾淨的原水以減少淨水費用，並可透過聯合操作而增加整體水資源利用量。而濁水溪沖積扇之水資源開發，短期應以停止地下水位下降與減緩地層下陷速率為目標；中期以抬升地下水位與停止地層下陷為目標；長期以地下水永續利用並不造成地層下陷為最終目標。制定區域地下水管理辦法，逐年檢討地下水水權量並於短期（如3年）進行小調整，中期（如5年）進行大調整，長期（如10年）進行總調整，以完善濁水溪流域地下水資源永續利用。

關鍵字

濁水溪流域 ； 名竹盆地 ； 聯合運用 ； 地下水開發 ； 地下水管理

並列摘要

The recent water exploitative facilities in Changhua and Yunlin Counties include the Hushan Reservoir and Niaozueitan Artificial Lake. Both of them are proposed to reduce the groundwater use in the Jhoushuei River alluvial fan to mitigate the land subsidence problem. However, despite the water supply from both of them, the water resources still cannot fully match the water demand in the Jhoushuei River alluvial fan. Due to the lack of water resources in this region, groundwater is still needed to supply the insufficient part of the water demand. Ming-Chu Basin is located between the Chi-Chi Weir and the mountain pass of Jhoushuei River at the top of alluvial fan. The thickness of recent sediment in the basin is about 30 meters. It is an aquifer with good storage and permeable properties and is an isolated groundwater reservoir as well. The recent sediment area around the river channel is a good place to exploit groundwater and hyporheic water resources. Accompanied with the use of the Chi-Chi Weir, the total quantity of water resources can be obtained by using the conjunctive operation. The strategy of water exploitation in Jhoushuei River alluvial fan should be separated into three steps. In short term, the strategy should focus on stopping the decrease of groundwater level and mitigating the subsidence rate. For the second step, the strategy is to rise the groundwater level and stop the land subsidence. For a sustainable strategy in long term, groundwater should be commonly used without inducing land subsidence problem. The groundwater management system should be developed based on controlling the quantity of groundwater right. The quantity of water right should be annual reviewed and considered for a small adjustment in short term (e.g., three years), a large adjustment in mid-term (e.g., five years), and a total adjustment in long term (e.g., ten years). It is after these adjustments that the groundwater resources can be sustainably used in the Jhoushuei River alluvial fan.

並列關鍵字

Jhoushuei River Watershed ； Ming-Chu Basin ； Conjunctive use ； Groundwater exploitation ； Groundwater management