"Today, a simple turn of the tap provides clean water-a precious resource. Engineering advances in managing this resource-with water treatment, supply, and distribution systemschanged urban life profoundly in the 20th century, virtually eliminating waterborne diseases in developed nations, and providing clean and abundant water for communities, farms, and industries." So states the US National Academy of Engineering on its selection of water supply systems to be among the top five greatest achievements of engineering in the twentieth century. But providing everyone with clean tap water, especially in urban areas, has yet to be achieved, even in developed nations. The world's population is growing by about 80 million people per year, and is predicted to approach 10 billion by 2050. Over 50% of people on our planet today live in urban areas and that percentage will grow. As populations continually move to cities for improved economic opportunities and a higher standard of living and as cities merge to form megacities, the design and management of water becomes an increasingly important part of integrated urban infrastructure planning and management.
IntroductionUrban water management involves the planning, design, and operation of infrastructure needed to meet the demands for drinking water and sanitation, the control of infiltration and stormwater runoff, and for recreational parks and the maintenance of urban ecosystems. As urban areas grow, so do the demands for such services. In addition there is an increasing need to make urban water systems more resilient to climate change. All this leads to the realization that urban water management must be an integral part of urban planning in general. Land use decisions impact water supply and wastewater system designs and operation, as well as measures needed for managing stormwater runoff. A functioning urban infrastructure system also requires energy which in turn typically requires water.Sustainable urban development must focus on the relationships between water, energy, and land use, and often on diversifying sources of water to assure reliable supplies. Integrated urban water management (IUWM) provides both a goal and a framework for planning, designing, and managing urban water systems. It is a flexible process that responds to change and enables stakeholders to participate in, and predict the impacts of, development decisions. It includes the environmental, economic, social, technical, and political aspects of urban water management. It enables better land use planning and the management of its impacts on fresh water supplies, treatment, and distribution; wastewater collection, treatment, reuse and disposal; stormwater collection, use and disposal; and solid waste collection, recycling, and disposal systems. It makes urban development part of integrated basin management oriented toward a more economically, socially, and environmentally sustainable mixed urban-rural landscape.