Explore Water

Global Water Crisis

 
The planet earth has over 70% of its surface covered with water, yet water is a word denoting acute scarcity almost everywhere. In order to grasp this, one has to take a look at the Hydrology of Planet Earth.

Due to constant contact of water bodies as well as the biosphere or the ecosystem( soil and all organisms) with solar radiation, there is evaporation of water. As the water vapour starts rising and enters cooler temperature, it starts condensing back into water molecules and drops downward. When large numbers of molecules come adjacent to each other, they are attracted towards each other and form a low density mass of water particles, which are clouds. Clouds are transported across the atmosphere through action of solar radiation forming wind currents (advection). As they encounter a mass of cold air they form denser bodies of water and precipitate (as rain or dew or snow or fog or sleet). Most of the precipitation (80%) occurs over the ocean itself and the rest over land. Some of the precipitation over land evaporates again, and the rest constitutes run-offs (as rivers and streams) as well as recharges of ground water. This is the hydrological cycle of earth. The following diagram illustrates this cycle:
 

How much water do we have?

 
Availability of all water:
Total .......................................................................... 1400 Million Km3
Salt water    (97%) ................................................. 1354 Million Km3
Fresh water (  3%) ................................................. 46 Million Km3
Distribution of Fresh Water on Lithosphere (Land):
Ice , Snow and Glaciers ( inaccessible) ........... 24.40 Million Km3
Ground water/soil moisture ................................. 20.00 Million Km3
Fresh water lakes/swamps ................................. 1.07 Million Km3
Rivers ....................................................................... 0.02   Million Km3
Distribution of Evaporation:
Hydrosphere (Oceans) ......................................... 505000 Million Km3
Lithosphere (landmass) ...................................... 72000 Million Km3
 

How does fresh water get contaminated?

 
Over Exploitation of Ground water
Agricultural Contaminants
Industrial Pollutants
Urban Pollutants
 

In the case of India

 
In a list of 122 countries rated on quality of potable water, India ranks a lowly 120. Although India has 4% of the world's water, studies show average availability of safe water is shrinking steadily. It's estimated that by 2020, India will become a water-stressed nation.
According to 2001 census, 68% of the households have access to safe drinking water. Yet other studies such as those of Water Aid show that less than 45% of the population has access to drinking water. In the last half century, till the 10th Plan, the government had spent Rs 1,105 billion on drinking water schemes. Yet the annual spending on treatment of water-borne diseases is still around Rs 67 billion.
Water from each of the 140 gazetted rivers in India, has been declared unfit for human use.
Ground water is also heavily contaminated with fluoride, arsenic, nitrates, heavy industrial chemicals and micro bacteria.
Each of the sample 950 sources of water from 300 villages across the country, which were chosen and studied by the International Organization Water Aid contained high levels of contamination with fecal coliform and fluoride.
The entire Gangetic Plain, Bengal, Bangladesh, Southern Nepal, and possibly Tripura and Manipur have heavy arsenic contamination in groundwater causing skin cancer, deformities and deaths.
Nitrates from fertilizers, septic tanks and sewers are another wide-spread source of contamination in almost all states.
Industrial pollutants are concentrated in ground water around every industrial area in the country, and they constitute a wide assortment: mercury, para-nitrophenol, sulphur, iron, zinc, cadmium, cyanide, chromium and lead.
The Central Pollution Control Board (CPCB) of the Government of India, after a national level survey of industrial pollution in 1994, identified 22 areas in 16 states, as being in a 'critical' condition. If one projects these data using post-1994 industrial growth rate of the economy, the number of critical areas could be well over 150, by now.
Thus fresh water on the lithosphere is not only dangerously low in availability,but also deteriorating quality.
 

Let us consider Hydrosphere First

 
Seawater desalination (SWD) technology made its beginning in the twentieth century. Experiments, as well as limited use have been made of Desalination. More than half of the world's desalination plants are located in an area encompassing the Persian Gulf, the Red Sea and Northern Africa. The US has 16% of the plants. The scale is not very big. The total water produced from desalination plants across the world in the year is just sufficient to meet world demand for 14 hours. There are reasons for this.
First, SWD is extremely expensive, both in terms of capital costs and operation and maintenance (O&M) costs, which are likely to be well over the usual engineering estimates of 10% of capital costs for Ground and Surface Water Systems, because of the extra corrosiveness of saline water and the heavy effluents from desalination plants.
Secondly, the environmental consequences of large-scale desalination, and the consequent creation of millions of tons of marine effluents day after day, are mind-boggling.
 

The Benefits of Atmospheric Moisture Extraction

 
This brings to the last alternative namely atmosphere and to Atmospheric Moisture Extraction (AME) technology.
This system has advantages in terms of
 
Plentiful Availability
Purity
Versatility
Economy
Ecological Sustainability