THE VULNERABILITY OF GROUNDWATER DUE TO EXPLOITATION ACTIVITIES AND CLIMATE CHANGE IN CA

MAU PENINSULA

Dao Hong Hai1*, Nguyen Viet Ky1, Bui Tran Vuong2

1 Geology and Petroleum engineering, Ho Chi Minh city University of Technology, 268 Ly Thuong Ky District 10, Ho Chi Minh city, Viet Nam, Tel: +84902.04.04.78, Email: dhhai@hcmut.edu.vn

2 Division for water resources planning and investigation for the south of Viet Nam, 59 street 2 Binh An ward, district 2, Ho Chi Minh city, Viet Nam, Tel: +84-8-37408433, Fax: +84-8-37408044

Email: liendoandctvmn@vnn.vn

Abstract

Ca Mau peninsula is one of the four areas of the Mekong Delta, and is surrounded by the Hau River, the East Sea and the West Sea. With the development of the agriculture and aquaculture over the years, the surface water systems in this area were mostly polluted and salinisated. In such natural, geographical, and economic circumstances, the surface water cannot satisfy the needs of people, and so groundwater resources is now the main source of supply in the region. In recent years, under the high rate of groundwater extraction, the groundwater level here has strongly decreased at the rates of 0.50; 1.76; 1.24; 1.98; 1.42 and 2.58 m per year for the aquifers qp3, qp2-3, qp1, n2

2, n21 and n1

3, respectively. Besides that, the phenomenon of global climate change and sea level rise are affecting many social – economic conditions and natural resources, including groundwater resources. In this paper, the authors use the modeling method to simulate groundwater flow in the period from 2000 to 2010, and use water level data from many monitoring stations for model calibration. The authors also use the rate of economic - population - social development to predict water demand scenarios of the region until 2030; and climate change scenarios from the Ministry of Natural Resources and Environmental to assess the impact on the calibrated model. Based on the results, the authors assess the vulnerable of groundwater resources in term of quality (the spread saltwater) and quantity (rate of decline in water level), and propose some reasonable responding approaches for the planning, exploitation and using activities of groundwater resources in Ca Mau peninsula.

Key words: the vulnerability of groundwater, impact of climate change, groundwater of Ca Mau peninsula.