Khai thác bền vững nước dưới đất dải cồn cát ven biển Bắc Trung Bộ: Tài nguyên nước dưới đất và trữ lượng có thể khai thác

Abstract

The north central coastal sand dunes, running from the north end of Nghe An province down to the south end of Quảng Trị province with the total length and exposed area of 271.9 km and 443.7 km², respectively, are the living places for almost 260.000 local resident. Freshwater lens in the sandy dunes - unconfined holocene aquifers (qh₂) - are the major sources supplying water for the demand of domestic use of local resident and their production activities. To sustainably exploit and use this specious water source it is required to get fully hydrogeological information of the aquifer, among which, information relevant to natural groundwater resources and exploitable groundwater reserves are always crucial. This paper report results of a study on evaluating natural groundwater resources and estimating exploitatble groundwater reserves of the freshwater lens mentioned above through analysing the hydogeological conditions, rainfall, evaboration and monitored groundwater hydrographs. The findings showed that rainfall is the main sources for groundwater formation and recharge for freshwater lens at the north central coastal sand dunes. Total natural groundwater resources is evaluated of about 1.633 billion m³, in which, the natural static resources is 1.462 billion m³ and the natural recharge from rainfall is 170.507 million m³. Total exploitable groundwater reserves is 370,862m³/day