The characterization of highway runoff water quality

Abstract

This diploma thesis gives an overview of the sources of highway runoff water, its nature, and its possible impacts. One part of my thesis has been developed at the Laboratório Nacional de Engenharia Civil (Portugal). As awareness for a responsible use of global water resources has increased in the last decades, it is essential to take an integral approach to pollution resulting from diffuse sources. In this context, a precise definition of highway runoff water characteristics in the scope of environmental impacts and for evaluating possible treatment measures is of particular importance. Potential measures aimed at minimizing the environmental impact of run-off water are evaluated. Therefore different approaches emerged. One possible way is the use of mathematical models to predict pollutant loads. As demanded from the Laboratório Nacional de Engenharia Civil, an investigation on the applicability of different models developed to calculate water quality and quantity for this purpose has been carried out. Therefore, an introduction to water quality modeling and an overview of existing models is given. Two of these models, the Simple Method and regression equations developed by the U.S. Geological Survey, were tested with data from Portuguese roads. Regrettably, on the base of the available data, no general statement to the applicability of these equations can be given.