Advances in GIS-Based Approaches to Groundwater Vulnerability Assessment: Overview and Applications


Elçi A.

in: Clean Soil and Safe Water, Quercia F.,Vidojevic D., Editor, Springer-Verlag , Dordrecht, pp.97-114, 2011

  • Publication Type: Book Chapter / Chapter Research Book
  • Publication Date: 2011
  • Publisher: Springer-Verlag
  • City: Dordrecht
  • Page Numbers: pp.97-114
  • Editors: Quercia F.,Vidojevic D., Editor
  • Dokuz Eylül University Affiliated: Yes

Abstract

The concept of groundwater vulnerability assessment is a key component of integrated watershed management. A wide range of approaches for assessing groundwater vulnerability were developed based on identified factors affecting the transport of contaminants in the vadose zone. These approaches can be divided into three major categories: (1) Overlay and index methods which are based on overlaying maps of factors contributing to contamination and subsequently assigning numerical scores or ratings to develop a range of vulnerability classes; (2) process-based methods based on mathematical contaminant transport models; and (3) statistical methods that infer relationships with areas where contamination has already occurred. Many of these approaches are based on a GIS. So-called hybrid methods that involve the combination of approaches are also used and are currently a topic of research. The first objective of this study is to overview recent advances in the GIS-based approaches to groundwater vulnerability assessments. Recent advances in GIS-based vulnerability assessment approaches offer ways to perform more reliable assessments. The integration of actual groundwater quality data in the assessment process, consideration of land use patterns and the use of vigorous optimization schemes are examples of recent improvements in this area. Another objective is to present a summary of a case study demonstrating the application of an optimization procedure for the vulnerability mapping method DRASTIC. The study area is the Tahtalı stream catchment, a major drinking water reservoir supplying 1950 L/s of drinking water to the city of Izmir, the third largest city in Turkey.