By Professor Poul Harremoes, this work explores the evolution of environmental engineering, particularly in urban drainage. Historically, the field relied heavily on empirical methods, exemplified by the Romans, who constructed impressive drainage systems without understanding hydraulics, a discipline that emerged only in the mid-1800s. The Renaissance marked a turning point, with figures like Galileo and Newton igniting the scientific revolution. This era saw Navier and Stokes apply Newton's laws to hydrodynamics, while St. Venant provided the first physics-based description of water flow in open channels. The integration of fundamental physical principles and empirical experience enhanced urban drainage design and performance. However, the mathematical complexities of the governing equations limited solutions to simpler cases until the advent of computers. These technological advancements enabled the simulation of complex hydraulic phenomena, allowing for a higher degree of confidence in model predictions, provided they are calibrated with actual performance data. This shift has transformed the approach to urban drainage, merging empirical knowledge with advanced computational techniques for improved infrastructure design.
