The SIVI index: a comprehensive approach for investigating seawater intrusion vulnerability for island and coastal aquifers

Abstract

Seawater intrusion is a major groundwater quality management issue for islands and coastal aquifers. In this paper, a new comprehensive index called the SIVI index has been proposed to assess the vulnerability of these aquifers to seawater intrusion. The index consists of eight parameters including: surface area of the aquifer affected; the intensity of intrusion; its seasonal variation; its evolution; aquifer type; the hydraulic conductivity of the aquifer; the height of groundwater levels above sea elevation; and distance of the aquifer from the coast. The SIVI index considers both the dynamic and intrinsic characteristics of the region to evaluate seawater intrusion vulnerability. The new index was applied to the Tourian aquifer located in Qeshm island in the Persian Gulf. The results show that the aquifer locally has a high vulnerability (SIVI index 0.54) to seawater intrusion as currently an area 9.5 km2 of the aquifer is in danger of being salinized. The presented SIVI classification method can be used to analyze vulnerability of aquifers and management of groundwater resources in any coastal region.