More than 50% of the world's population already live in cities, and the proportion is rising extremely rapidly towards developed country levels of more than 90%. Groundwater from wells is the major source of water supply for many of these cities, however, groundwater is polluted by the cities that overlie it and sewerage systems are often absent, or leak. Industrial landuse implies the use of large quantities of chemicals, and it is the poor disposal and accidental spillage of these chemicals which results in the contamination of virtually every industrial site in the world. Much of this pollution migrates deeper to damage groundwater. Groundwater has slow turnover time, often measured in decades and centuries, reducing the self-cleansing capacity. Urban aquifers are therefore vitally important but very fragile, easily damaged and slow to repair. Urban groundwater problems and solutions vary greatly around the world. Mature cities
Table of Contents
1. Values and Functions of Groundwater under Cities2. Characteristics of Urban Groundwater3. Sources, Types, Characteristics and Investigation of Urban Groundwater Pollutants4. Mature Industrial Cities5. Rapidly-Urbanising Arid-Zone Cities6. Urban Areas of Sub-Saharan Africa: Weathered Crystalline Aquifer Systems7. Cities Overlying Karst and Karst-like Aquifers8. Groundwater Management in Urban Alluvial Aquifer Systems: Case Studies from three continents: Agadir, Lima and Los Angeles9. Shallow Porous Aquifers in Mediterranean Climates
David Lerner came to academic life via a water authority and international consultants, and has taught in both Geology and Civil Engineering departments. He leads the Groundwater Protection and Restoration Group (GPRG) at the Department of Civil and Structural Engineering at the University of Sheffield, UK.
His publications range over many current issues of hydrogeology, including urban groundwater, groundwater protection, designing landfills, the behaviour of organic chemicals in the subsurface, and natural attenuation of pollutants. He is a Fellow of the Royal Academy of Engineering.
The book discusses rapid urbanization of the developing world as it places greater pressure on city environments and its pace of growth outstrips the planning and control infrastructure. Easy access to groundwater makes it the main source of water for the world's population and places it at severe risk of pollution in cities because of the density of polluting activities, such as industrial plants, pipelines, sewers, landfills, etc. The issue of urban groundwater encapsulates many modern problems: sustainability, rapid urbanization and rising living standards, pollution prevention, inadequate data, and complex management issues of optional use of resources. The story of each city is different but some themes are common, such as climates, geology and development status. The book comprises two parts. The first part (Chapters 1-3) gives a view of urban development from the groundwater perspective; the disparate and conflicting values of groundwater for water supply, efficient disposal, amenity and ecology; and overviews pollutants by type and by source. Chapters 4-9 form the larger part of the book and deal with case studies of several cities to draw out the common threads across cultures and continents. Professional hydrogeologists, urban planners and water supply engineers, as well as students in these fields can use the book to provide a new perspective on the often damaging effects that cities have on their hidden but valuable groundwater.
Fakhry A.Assaad, Consultant Geologist and Data, Analyst, Tuscaloosa, AL, USA