How to deplete cities of fresh water and pollute it too– A Case Study Of Jaipur

The lake at Nainital, a town in the Himalayas

With a rising population on our planet, particularly in cities, ensuring fresh water supplies of a good quality is an issue facing many cities around the world.

Cities derive their water from surface sources such as lakes and rivers or from underground sources. It seems that in India two thirds of fresh water requirements are met by ground water. With an increase in human activity both sources of water are getting depleted besides getting polluted. Surface water is polluted if waste water from cities and industries is dumped directly into natural lakes and rivers without treatment. Such pollution can be reduced if  water is first directed/dumped into artificial canals and lakes instead. From here it purifies slowly by bacterial action and the water that seeps into ground is purified by filtration through soil. However some pollutants such as nitrates from fertilizers that dissolve in water can reach ground reservoirs polluting ground water too. Ground Water is polluted if erroneous water harvesting systems that feed polluted surface water directly into sub soil water through artificial boring are used or if surface pollution, especially from inorganic industrial sources is high.

In order to augment ground water and prevent its depletion the following steps are helpful

1. Creation of lakes, dams and reservoirs or expanding existing ones to store rain water in or near the city. These recharge ground water continuously.
2. Increasing river and canal pathways through and near the city while preventing city waste from entering them.
3. Not directing city waste water too far away from the city but rather directing them to wetlands or waste water reservoirs near the city.
4. Restricting  use of fertilizers and other chemicals in industries and farms near the city incase these are reaching ground water.

It goes without saying that if one wishes to deplete a city of fresh water precisely the reverse of what is suggested in the four steps above should be done. This is precisely what has been happening in one Indian city -Jaipur. The city is located in a relatively arid zone. Prior to 1947 it was ruled by a Royal Family. The family constructed several dams and lakes in and around the city and these helped to augment the water resources of Jaipur State. The city therefore developed as a prosperous and beautiful city famous for its charms around the world. Since 1947 an elected democratic government took over the governance of the city. It has neglected water resources since it has other short term goals. After all elected governments are only for four or five years and concerned at the most with the next term, not the long term future. A dam known as the Ramgarh Dam that supplied the city with water from 1931 to 2005 and helped to maintain ground water table was first dried up by blocking its inlets. The dam area was then leased to farmers. A few years ago when some water collected in this dam due to excess rains it was quickly pumped out to maintain the farms and the revenue from them. Within the city encroachments were permitted on the only river (Dravyavati) that flowed through the city so that it has changed into a narrow drain. Several of the lakes in and around the city were similarly dried up by blocking their inlets for construction. The famous Jal Mahal Lake of the city was leased out to a private company permitting it to reclaim its land and reducing its size. When interested citizens protested in a court of law they won their case but the elected government is considering appealing against the decision in a higher court. All this was for short term gains. As a result, the city began facing severe water shortages. The ground water table fell and now the city survives partly by water brought from a dam far away by pipeline. However it is insufficient to supply the water to the city even twice a day for a few hours as was the practice until few years ago.

As modernization of Jaipur proceeds with the development of an international airport and a metro service the most basic requirement of life - water is being overlooked. Without abundant water the city is likely to deteriorate into a ghost city rather than a modern one.

Further, it seems that many in Jaipur city have discovered a method to pollute the ground water too. They strongly recommends directing polluted surface water directly into ground water through bore wells so that pollutants reach and pollute ground water. They call it rain water harvesting. It is an incorrect interpretation of rain water harvesting. The correct method is to store rain water in surface ponds, lakes and dams so that it reaches ground water by natural filtration. 

Very sadly some engineers lacking in full technical knowledge of the process have proposed ill designed rain water harvesting systems in cities that harm rather than benefit mankind. Some of these harmful practices have even been worked into city regulations by unsuspecting politicians.  They propose collecting and directing rain water through bore holes into ground. This is the quickest way to destroy available drinking water supplies for mankind because in this method surface pollution is added to sub soil water, thereby destroying its potable quality.

The proper way to store rain water is in surface ponds and lakes so that it percolates slowly and naturally into ground, whereby through both bacterial action and ground filtration, it converts into potable sub soil water which may then be pumped out and used as potable water with minimal treatment.

In contrast the photo is one of Nainital town built around a beautiful Himalayan Lake. Because of the lake this city will never be short of fresh water. However if the water is taken directly from the lake it can not be used for drinking because of pollution. Instead an abundant city water supply of good quality is maintained by bore wells constructed around the lake.