Visualizing the Impacts of Dewatering on Ground Water and Soil Quality Using GIS

Abstract

There is mounting evidence that the increasing size of the construction industry may lead to significant changes in the global environment. Dewatering, as a crucial component of the construction industry, may have detrimental consequences on the soil and groundwater quality. Dewatering is a technique used to lower the high-water table during construction. The possible effects of dewatering on the soil and ground water quality were visualized and investigated using GIS technology. The analyses were conducted at small temporal and spatial scales. The aim is to give insights in the magnitude and the direction of the dewatering’s impacts. Furthermore, the methodology and the results described in this study will contribute to the UAE national analysis of the impacts of dewatering on the water sector. However, field measurements of water table, groundwater qualities, soil salinity levels, geographic locations and elevations were used to verify the spatial analysis conducted. The temporal and spatial variations of the groundwater/soil quality, in the study area, were determined and visualized. Then the impacts of the dewatering were quantified and evaluated. It is found that dewatering has quantifiable impacts on the soil and ground water quality. The results show drastic but reversible changes in water salinity and light but persistent/ irreversible changes in soil salinity. The magnitude of the increase in the water salinity is in the range of 0.4 g/L – 1.8 g/L. While the magnitude of the change in the soil salinity is in the range of 0.02 – 0.04 g/L.