Proposal for a Criteria Set to Protect against Degradation for Sustainable Groundwater Exploitation in High Mountainous Water-Scarce Areas in the South-Central Region of Vietnam

Abstract

Groundwater plays a crucial role in providing water for domestic use and production. However, continuous extraction pressures have shown signs of degradation and depletion, especially in high mountainous water-scarce areas in Vietnam in general and the South-Central region in particular. The high mountainous water-scarce areas in the South-Central region consist of 28 mountainous regions across 7 provinces: Quang Nam, Quang Ngai, Binh Dinh, Phu Yen, Khanh Hoa, Ninh Thuan, and Binh Thuan. Calculations show that the area contains 8 water-bearing layers/zones, including Pleistocene sedimentary pore aquifers, fissure, fissure-pore sedimentary aquifers ranging from Archeozoic to Mesozoic ages, and water-bearing zones along tectonic faults in intrusive and volcanic rocks. The total groundwater exploitable volume is 50,691 m³/day, with Khanh Hoa province having the largest volume at 12,758 m³/day, and Ninh Thuan having the smallest at 1,834 m³/day. The forecasted total extraction rate is 12,816 m³/day, capable of supplying 128,160 people with a standard water usage of 100 liters/person/day. To protect and prevent groundwater degradation in this area, the authors propose a criteria set comprising three groups of criteria: Criteria group for preventing degradation in volume (3 criteria with 6 indicators); Criteria group for preventing environmental degradation (4 criteria with 5 indicators); Criteria group for preventing degradation due to socio-economic factors (4 criteria with 6 indicators). The assessment results of groundwater protection against degradation in the area reveal that there are 3 regions with low protection levels and 25 regions with moderate protection levels.