The Gist of Science Reporter: August 2014
The Gist of Science Reporter: August 2014
- Water Footprint: Time to Reduce the Impact ()
- India’s Water Footprint ()
- Energy from Mounds of Waste (Only For The Subscribed Members)
- Classifying Waste (Only For The Subscribed Members)
- Treating Solid Waste (Only For The Subscribed Members)
Water Footprint: Time to Reduce the Impact
Water is essential for life. Without water neither would plants and animals survive nor would industries thrive. We all know and appreciate these facts.
But do we know that millions around that word trudge miles in search of water? Nearly 1 billion people do not have access to clean drinking water, which is making their families sick? According to the United Nations, water use has grown at more than twice the rate of population increase in the last century. Yet, about one in nine people, lack access to clean drinking water, which kills children at a rate equivalent of a jumbo jet crashing every four hours.
Many countries in arid and semi-arid regions on the world (e.g., Central and West Asia, North Africa) are already close to or below the threshold for water scarcity. Environmentalists working in different parts of the world unequivocally claim that up to two-thirds of the world population could experience of the world population could experience water scarcity over the next few decades.
Pollution of water bodies is further limiting the amount of water available for use. Similarly, change in precipitation patterns s a result of climate change are adding to the pressures on our global water resources. The challenge humanity is facing today is how to conserve and manage this important natural resource. The United Nations declared the year 2013 as the International Year for Water Cooperation.
The Water Footprint
So what is this water footprint and how is it going to help solve the crisis? Many indicators are today being used all across the world to correlate resource consumption in economic terms. United Nations determines each country’s ratio of water consumption to water availability, that is, its use-to-resource value as one of the indices for calculating water usage by a country. The indicator has been used for long as a good gauge of overall pressure on water resources. However, not much has been gained in terms of conservation and management of this important ecological resource using these parameters.
Water footprint is a comprehensive measure of freshwater consumption that connects consumptive water use to a certain place, time, and type of water resource. It looks at both direct and indirect water use of a consumer or producer. The water footprint of an individual, community or business is defined as the total volume of freshwater used to produce the goods and services consumed by the individual or community or produced by the business. It includes the use of:
- blue water (rivers, lakes, aquifers)
- green water (rainfall in crop growth)
- grey water (water polluted after agricultural, industrial and household use).
The concept aims primarily at illustrating the hidden links between human consumption and water use and between global trade and water resources management. It has been brought into water management science to show the importance of human consumption and global dimensions in good water governance. The calculation for a water footprint includes the total amount of freshwater consumed along the supply chain of a product. For instance, the amount of water used for a cotton dress purchased from a retail outlet or a food product from a grocery store.
Water use in agriculture is slated to increase as world food demand rises. Agriculture already accounts for about 70% of water consumption worldwide, and the United Nations projects a 50% to 100% increase in irrigation water by 2025. Agriculture is by far the largest global consumer of freshwater. In this sector, a water footprint measures the volume of evapotranspiration or water use of a crop per unit mass of yield. Comparing water footprints of different management practices in agriculture can help evaluate drought tolerance, water use efficiency, the effective use of rainfall, and the significance of irrigation.
Calculating Water Footprint Calculation of water footprint is easy and can be done by pressing a button. However, it has unimaginable advantages. If an individual gets to know how much extra water one is using, probably one can be more cautious and show a sense of responsibility towards conservation.
Simple water footprint calculators have been designed by various national and international agencies to calculate the amount of water used in day-to-day activities. These are handy and work with a high degree of precision and can be used free on the web. Simple calculators work on food consumption, indoor domestic use, outdoor domestic use, and industrial goods consumption. The National Geographic uses a more graphic intensive approach to calculate water use in our household, diet, energy use, and shopping/ services. The H20 Conserve Calculator is focused on the United States and calculates the water footprint on a household basis through similar questions to the other calculators.
India’s Water Footprint
India accounts for high water footprint on account of various reasons. One of the significant reasons is increasing demand because of the vast population. Moreover, in India people have a water-intensive consumption pattern and lifestyle. India is also an agricultural economy and most of our agricultural crops need high inputs in terms of irrigation. The water requirement per unit of crop production is relatively large and because of water inefficient agricultural practices, water productivity in terms of output per drop of water is relatively low. The focus today should be on reducing this footprint. Some of the viable options for a country like India are to adopt production techniques that require less water per unit of product. Water productivity in agriculture can be improved, for instance, by applying advanced techniques of rainwater harvesting and supplementary irrigation. A second way of reducing water footprint is to shift to consumption patterns that require less water, for instance by changing food habits, changing food basket and include local, indigenous, and seasonal foods in our diet. This will have a long term impact on many other associated aspects and save the country’s resources.
Another aspect that needs review is our subsidy policy. Water is a highly subsidized commodity in India. People pay nominal bills for water and hence there is no control over over-exploitation and wastage. Reducing subsidy will probably help in securing this resource and force every individual to reassess the way we have been using this precious resource. Water costs are generally not well reflected in the price of products due to the subsidies in the water sector. Besides, the general public is hardly aware of the water requirement in producing their goods and services.
A subtler approach to reduce the water footprint would be raising awareness though integrated campaigns of the negative impacts of increasing footprint on environment, and introduction of other incentives such as water-credit schemes to make people change their consumption behaviour.
Governments can promote an international agreement on world-wide water footprint reduction. National targets on water footprint reduction can be translated to specific reduction targets for products, producers, industry, goods, etc. so that all the sectors are covered.