台灣因國民日益重視休閒與養生，溫泉區的發展也日益蓬勃，而溫泉需求量日漸增加後，也促使溫泉井大量的鑿設與開發。大量的溫泉開發與抽用，若管制不及，常有超抽的危險，將使溫泉水位下降、水溫降低，傷害溫泉區產業的發展。台灣南部屏東縣四重溪溫泉的超抽現象，甚為明顯，早年溫泉露頭自然湧出溫泉，但近年因溫泉井大量開發，溫泉露頭因而乾枯消失，目前溫泉區內都需依賴三、四百公尺深的溫泉井抽水，但因自然補注趕不上人為的抽用，溫泉水位日漸下降，可能已達地面下數十公尺深（陸島工程顧問，2004；李和祥，2004）。地下水（或溫泉水）永續利用的基本定義為：「抽用量及補注量達到平衡，使地下水位能維持穩定、不持續下降」（Barraque，1998；Burke 和Moench，2000；Custodio， 2002；Price，2002；FAO，2003）。因此溫泉水資源抽用的總量管制，需基於補注量的多寡，其有賴於足夠的水位及水溫觀測數據。然而台灣的溫泉區管理，仍在起步階段，例如四重溪溫泉，雖然當地業者已感受到水位日漸下降，迫使鑿井需越鑿越深，早期約一百多公尺、然後是加深至二三百公尺，但是水位的變化仍沒有可靠的數據。溫泉的水位下降，將衍生許多問題，如鄰近的河水及淺層地下水是否會因此滲入溫泉含水層中？溫泉水質及溫度是否因此產生變化？如果有變化，可能會危及溫泉產業的發展，但是變化的速度可能有多快？為解決以上問題，並探討四重溪溫泉永續利用之道，本研究為一初步的嘗試，藉由在多口溫泉生產井中放置水溫、水位及電導度監測儀器，以所獲得的該些重要參數的變化數據，推導可能的溫泉生成模式，並推測四重溪溫泉的抽用量及補注量，提供本區溫泉水資源永續利用之參考。 Recently hot springs recreation and tourism are valued and popular at the regional and national levels in Taiwan. The increasing hot spring water withdrawn and wells drilled for recreation use are causing the depletion of hot spring resources. The Szchungshi hot spring in South Taiwan, for example, had lost its hot spring outcrop in a decade for the overexploitation of hot waters by wells. As more and more wells were sunk, water pressure and temperature of hot water dropped across much of the Szchungshi. Sustainability is defined implicitly as a level at which draft and recharge are balanced (the ‘sustainable yield’ of an aquifer). This assumes that asteady state can be achieved in which water levels are stabilized. As in most discussions concerning groundwater (or hot spring water) overabstraction, these statistics focus on rates of water-level decline and the degree to which extraction estimates exceed replenishment estimates. However, The provenance of the replenishment, whether recharge from the surface or leakage from adjacent aquifers is rarely known with any precision in Taiwan. In this study, we will install pressure, temperature, and electrical conductivity meters in hot spring wells (up to 4 wells, depth in 200-300m) in Zachungshi to monitoring the year-round data for constructing its hot water occurrence and cold water mixing mechanism.
