Modeling of Urban Drainage and Stormwater

Abstract

AbstractThe construction and operation of urban drainage and stormwater systems have historically been driven by the objectives of maintaining public hygiene and preventing flooding. All over the world, cities have grown rapidly during the last century, and city authorities have built and continuously expanded storm and wastewater drainage facilities. Many old cities have developed according to their varying historical needs and visions. Hence, the layout and design of the infrastructure have gradually developed into rather complex systems, which require tools to handle such situations.An understanding of the physical system and its interaction with the environment is a prerequisite for effective planning and management of urban drainage and stormwater systems. In this respect, computer models provide the opportunity for well‐structured analyses of the current performance of a system and the effect of potential changes in the system; they offer a sound scientific framework for coordinated management and planning. Apart from assessing different scenarios, the models also help to improve process understanding. Urban drainage models are used to understand the often rather complex interaction between rainfall and overflow/flooding. Once the existing conditions have been analyzed and understood, alleviating schemes can be evaluated, and the optimal scheme implemented.Today's advances in computer technology allow many cities all over the world to report overflows from their sewers yearly using a combination of measurements and modeling, and in many places, they manage local and minor flooding problems using computer‐based solutions. This involves developing computer models of the drainage/sewer system, for instance, by using software such as InfoWorks, MIKE URBAN, MOUSE, PCSWMM, and SWMM. All are hydrodynamic modeling packages that solve the one‐dimensional equations of St. Venant.