Global water scarcity can no longer be handled in the traditional way by increasing supply, developing new sources, and expanding extraction from existing sources as this approach is not sustainable. New approaches must be adopted to balance supply and demand, including improved water management and conservation, rainwater capture, “virtual water” exchange, and desalination of groundwater and seawater. Many savings can occur through the use of improved irrigation strategies and technology. Despite the water independence that desalination offers, its energy needs and costs are still high, making it a remote possibility for most, and its impacts on the environment are quite concerning.

Introduction

As mentioned in Chapter 10, the world is rapidly moving toward a water crisis, with water scarcity affecting millions of people, particularly the poorest. Water consumption has skyrocketed in most developed and developing countries as a result of a rapidly increasing world economy, irrigation needs of crops to feed a growing population, and augmentation of cities and industries' water demands. Allocation of water to preserve the environment has recently become an added demand placed on oversubscribed water supplies.

A growing water crisis may not always be immediately apparent at the local level when it takes the form of aquifer overpumping and falling water tables. Even so, traditional responses to water scarcity – expansion of supply by building dams and drilling more wells – are now limited.