Urban Groundwater Issues—An Introduction

Many of the world’s urbanised regions grew at a slow but consistent rate for thousands of years. In many countries, urban growth rates accelerated in the 19th century due to the industrial revolution. Today, however, most rapid growth is occurring in Asian and Latin American countries where concerns have been raised that the rates may be environmentally unsustainable. Currently, three billion people live in urban areas, representing half the world’s population. This number could double within fifty years. Large urban areas are the economic engines of the world. However, they exert an enormous stress on natural resources and the immediate environment—groundwater, in particular, is seriously compromised. The earliest impacts were recognised in areas where excessive use of groundwater led to a regional lowering of the Potentiometrie surface and promoted such problems as reduced well yields, saline intrusion and land subsidence. Today, the most common urban groundwater issues concern groundwater pollution from urban and industrial sources and recharge management, mainly in the context of rising water levels. As a science, urban hydrogeology is relatively young. Issues are complex and much remains to be done. Nevertheless, a wealth of knowledge has been gained, many issues are well documented and problems are generally well understood. Solutions are beginning to emerge and there is encouraging evidence that better methods of impact prediction, groundwater protection and urban groundwater management will provide major benefits. There is now a recognition that groundwater must form an integral part of the urban planning process if large urban and industrial regions are to be environmentally sustainable. It is essential, however, that groundwater professionals adopt a proactive role if their skills and knowledge are to be fully incorporated in this process.