WATER SCARCITY
Gulsim Shaimerdenova (Kazakhstan)
Kazakh National Agrarian University
Scientific director: Sirgebayeva S.T.
Abstract: Water scarcity is the lack of sufficient available water resources to meet water needs within a region. It affects every continent and around 2.8 billion people around the world at least one month out of every year. More than 1.2 billion people lack access to clean drinking water.
Water scarcity involves water stress, water shortage or deficits, and water crisis. While the concept of water stress is relatively new, it is the difficulty of obtaining sources of fresh water for use during a period of time and may result in further depletion and deterioration of available water resources. Water shortages may be caused by climate change, such as altered weather patterns including droughts or floods, increased pollution, and increased human demand and overuse of water. A water crisis is a situation where the available potable, unpolluted water within a region is less than that region’s demand. Water scarcity is being driven by two converging phenomena: growing freshwater use and depletion of usable freshwater resources.
The main causes of «water crisis»
Tundisi et al. (2012) highlight that, in the broad social, economic and environmental context of the 21st century, the following principal problems and processes are the main causes of the «water crisis»:
• Intense urbanization, increasing the demand for water, expanding the discharge of contaminated water resources, while there is tremendous demand for water for drinking and economic and social development (Tucci, 2008).
• Water stress and scarcity in many regions of the planet due to alterations in availability and increased demand.
• Poor infrastructure or infrastructure in a critical state in many urban areas, with losses in the network of up to 30% after treatment.
• Problems of stress and scarcity due to global changes with extreme hydrological events increasing the human population’s vulnerability and compromising food security (intense rains and intense periods of drought).
• Problems caused by the lack of articulation and lack of consistent actions of governability of water resources and for environmental sustainability.
• This set of problems has local, regional, continental and planetary dimensions. These problems contribute to:
• An increase and exacerbation of sources of contamination.
• Alterations of the sources of water resources — with scarcity and decreased availability.
• Increased vulnerability of the human population due to contamination and difficulty of access to good quality water (potable and treated).
The main problem of water resources — water scarcity
Water scarcity is the lack of sufficient available water resources to meet water needs within a region. It affects every continent and around 2.8 billion people around the world at least one month out of every year. More than 1.2 billion people lack access to clean drinking water.
Water scarcity involves water stress, water shortage or deficits, and water crisis. While the concept of water stress is relatively new, it is the difficulty of obtaining sources of fresh water for use during a period of time and may result in further depletion and deterioration of available water resources. Water shortages may be caused by climate change, such as altered weather patterns including droughts or floods, increased pollution, and increased human demand and overuse of water.A water crisis is a situation where the available potable, unpolluted water within a region is less than that region’s demand. Water scarcity is being driven by two converging phenomena: growing freshwater use and depletion of usable freshwater resources.
The reduction of water scarcity is a goal of many countries and governments.
Water stress
The United Nations (UN) estimates that, of 1.4 billion cubic kilometers (1 quadrillion acre-feet) of water on Earth, just 200,000 cubic kilometers (162.1 billion acre-feet) represent fresh water available for human consumption.
More than one in every six people in the world is water stressed, meaning that they do not have access to potable water. Those that are water stressed make up 1.1 billion people in the world and are living in developing countries. According to the Falkenmark Water Stress Indicator,a country or region is said to experience «water stress» when annual water supplies drop below 1,700 cubic metres per person per year. At levels between 1,700 and 1,000 cubic meters per person per year, periodic or limited water shortages can be expected. When a country is below 1,000 cubic meters per person per year, the country then faces water scarcity . In 2006, about 700 million people in 43 countries were living below the 1,700 cubic metres per person threshold. Water stress is ever intensifying in regions such as China, India, and Sub-Saharan Africa, which contains the largest number of water stressed countries of any region with almost one fourth of the population living in a water stressed country.The world’s most water stressed region is the Middle East with averages of 1,200 cubic metres of water per person. In China, more than 538 million people are living in a water-stressed region. Much of the water stressed population currently live in river basins where the usage of water resources greatly exceed the renewal of the water source.
Water crisis
When there is not enough potable water for a given population, the threat of a water crisis is realized. The United Nations and other world organizations consider a variety of regions to have water crises of global concern.Other organizations, such as the Food and Agriculture Organization, argue that there are no water crises in such places, but steps must still be taken to avoid one.
Causes of water crisis
• There are several principal manifestations of the water crisis.
• Inadequate access to safe drinking water for about 884 million people
• Inadequate access to sanitation for 2.5 billion people,which often leads to water pollution.
• Groundwater overdrafting (excessive use) leading to diminished agricultural yields.
• Overuse and pollution of water resources harming biodiversity
• Regional conflicts over scarce water resources sometimes resulting in warfare.
Water scarcity’s effects on environment
Water scarcity has many negative impacts on the environment, including lakes, rivers, wetlands, and other fresh water resources. The resulting water overuse that is related to water scarcity, often located in areas of irrigation agriculture, harms the environment in several ways including increased salinity, nutrient pollution, and the loss of floodplains and wetlands. Furthermore, water scarcity makes flow management in the rehabilitation of urban streams problematic.
Through the last hundred years, more than half of the Earth’s wetlands have been destroyed and have disappeared.These wetlands are important not only because they are the habitats of numerous inhabitants such as mammals, birds, fish, amphibians, and invertebrates, but they support the growing of rice and other food crops as well as provide water filtration and protection from storms and flooding. Freshwater lakes such as the Aral Sea in central Asia have also suffered. Once the fourth largest freshwater lake, it has lost more than 58,000 square km of area and vastly increased in salt concentration over the span of three decades.
Measurement of water scarcity
Hydrologists today typically assess water scarcity by looking at the population-water equation. This is done by comparing the amount of total available water resources per year to the population of a country or region. A popular approach to measuring water scarcity has been to rank countries according to the amount of annual water resources available per person. For example, according to the Falkenmark Water Stress Indicator, a country or region is said to experience «water stress» when annual water supplies drop below 1,700 cubic metres per person per year. At levels between 1,700 and 1,000 cubic metres per person per year, periodic or limited water shortages can be expected. When water supplies drop below 1,000 cubic metres per person per year, the country faces «water scarcity». The United Nations’ FAO states that by 2025, 1.9 billion people will live in countries or regions with absolute water scarcity, and two-thirds of the world population could be under stress conditions. The World Bank adds that climate change could profoundly alter future patterns of both water availability and use, thereby increasing levels of water stress and insecurity, both at the global scale and in sectors that depend on water.
Ways to solve the water problem
There are several ways to solve the water problem: construction of water reservoirs. In the world of 30 thousand. Reservoirs. However, large reservoirs have a negative impact on the environment: change the mode of groundwater affect the vegetation, occupy large tracts of fertile land, waterlogged surrounding soil, going trough the earth’s surface by large reservoirs, increased seismic activity near major reservoirs in Asia, Africa, North America, etc.
Interbasin transfer of river flow.
Desalination of sea water.
Transportation icebergs.