Assessment of Environmental Impacts in Civil Engineering Projects Using Remote Sensing and GIS Techniques

Abstract

Environmental Impact Assessment (EIA) in civil engineering is a systematic and multidisciplinary decision-support process aimed at identifying, predicting, evaluating, and mitigating all biophysical, social, and economic effects of infrastructure development before it is put into effect. EIA serves as an important governance tool that is able to reconcile development goals with environmental protection and sustainable resource management, as land use is fundamentally changed by civil engineering projects such as highways, dams, bridges, airports, urban developments, water supply systems, and industrial facilities, as well as the resulting shift in land use patterns, hydrological systems, ecological networks, and community structures. The formal development of EIA as a regulatory tool began with the emergence of environmental policy initiatives in the late 1980s, including the United States' National Environmental Policy Act (NEPA), which established environmental review procedures for federally funded projects. Since then, EIA has been embraced worldwide and has become part of national laws, safeguards for multilateral development banks, and international environmental conventions, and has influenced the practice of civil engineering in the modern era by requiring environmental due diligence and stakeholder engagement procedures to be followed. EIA, at its heart, is based on the notion of anticipatory planning, where the potential impacts on the environment are assessed before irreversible decisions are taken. In civil engineering projects, this entails a thorough baseline study to determine an existing environmental condition, such as air quality, water resources, soil condition, biodiversity, land use, noise level and socio-economic demographics. Baselines serve as a reference point to compare with predicted impacts on the project. The potential for impacts is estimated using predictive modelling techniques, including hydrological modelling, traffic flow modelling, air dispersion modelling and ecological risk assessment. These evaluations are further strengthened by the use of Geographic Information Systems (GIS), remote sensing, and environmental monitoring technologies, which provide greater spatial accuracy and analytical strength.