• Assessment of Groundwater Quality on a Watershed Scale by Using Groundwater Quality Monitoring Data
  • Jeong Jik Kim1·Yunjung Hyun1*

  • 1Water and Land Research Group, Korea Environment Institute, Sejoung 30147, South Korea

  • 지하수수질측정망 자료를 이용한 유역단위 지하수 수질등급 평가
  • 김정직1·현윤정1*

  • 1한국환경연구원 물국토연구본부

  • This article is an open access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/4.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.


In Korea, groundwater quality is monitored through National Groundwater Quality Monitoring Network (NGQMN) administered by Ministry of Environment. For a given contaminant, compliance to groundwater quality standards is assessed on a annual basis by monitoring the number of incidents that concentration exceeds the regulatory limit. However, this approach provides only a fractional information about groundwater quality degradation, and more crucial information such as location and severity of the contamination cannot be obtained. For better groundwater quality management on a watershed, a more spatially informative and intuitive method is required. This study presents two statistical methods to convert point-wise monitoring data into information on groundwater quality status of a watershed by using a proposed grading scale. The proposed grading system is based on readily available reference standards that classify the water quality into 4 grades. The methods were evaluated with NO3-, Cl-, and total coliform data in Geum River basin. The analyses revealed that groundwater in most watersheds of Geum River basin is good for domestic or/and drinking with no treatment. But, there was notable quality degradation in Bunam seawall and So-oak downstream standard watersheds contaminated by NO3- and Cl-, respectively.

Keywords: groundwater quality monitoring network, grading system, watershed scale, statistical method, Geum-river basin

This Article

  • 2021; 26(6): 186-195

    Published on Dec 31, 2021

  • 10.7857/JSGE.2021.26.6.186
  • Received on Dec 15, 2021
  • Revised on Dec 16, 2021
  • Accepted on Dec 20, 2021

Correspondence to

  • Yunjung Hyun
  • Water and Land Research Group, Korea Environment Institute, Sejoung 30147, South Korea

  • E-mail: yjhyun@kei.re.kr