Essay On Water Scarcity

Water is thought as a renewable resource, because it is replenished by rainfall (PIMENTEL – water resources – agricultural and environmental issues). Notwithstanding, its amount varies over different regions at different times of the year. Human water necessity is almost the same throughout the year; therefore human communities try to control its availability through the construction of dams in some major rivers and pumping of groundwater.

At least 1.2 billion people live in areas of physical water scarcity and another 1.6 billion people confront economical water shortage, that is when the countries do not have the infrastructure to take water from rivers and aquifers (UN http://www.un.org/waterforlifedecade/scarcity.shtml) as shown in figure 1. Besides the scarcity in drinkable water supply, there are other problems such as water pollution (harming biodiversity of rivers and lakes, and transmitting diseases) and other water usages such as food production, management of human wastes and dilution of pollutants.

In the entire world, there are signs of decline in water availability. This can be exemplified by the reduction in the area occupied by Africa’s Lake Chad and by the Aral Sea (PLAN B 2.0 PAGE 50). Besides a lot of countries such as China, United States, India, Mexico, Jordan, Syria, Pakistan and South Korea are overpumping their aquifers and watching as their water tables fall (Shah et al. 2007 cited in Fraiture & Berndes, 2009). Most of the groundwater available is located in fossil aquifers where depletion brings pumping to an end (PLAN B 2.0 pages 41, 42, 43). Another sign of decline is the fact that some rivers do not reach the ocean anymore, between them are the Colorado and the Yellow river, and some other major ri...

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...l production from food crops is not economically viable, thus the biofuel production from lignocellulosic plants is less likely to be. There are uncertainties regarding if the lignocellulosic crops are really going to decrease the water consumption of ethanol production. And finally, biofuel production can cause food insecurity within the producer countries and sometimes it can be expanded to the rest of the world due to the increase of prices.

Therefore, with the current previsions of growth in world and urban population, meat consumption and biofuel production, it seems impossible to meet all the demands. The water supply is facing major problems in different locations of the world and the climate change is also affecting the availability of water. Thus society will have to change its overall behaviour to confront the upcoming water, land, energy and food issues