Contaminated Water

Contaminated Drinking WaterA recent United States Geological Survey (USGS) study of public drinking water wells in California, Connecticut, Nebraska and Florida found that some were contaminated, but in amounts so minimal, human health was unlikely to be affected. The USGS tracked the movement of contaminants in groundwater and public-supply wells in four different aquifers.

According to the USGS, wells are not equally vulnerable to contamination because of differences in three factors: the general chemistry of the aquifer, groundwater age, and direct paths within aquifer systems that allow water and contaminants to reach a well. The importance of each factor differs among the various aquifer settings, depending upon natural geology and local aquifer conditions, as well as human activities related to land use and well construction and operation. However, the USGS feels that the study of the four different aquifer systems can be applied to similar aquifers and wells throughout the nation.

Examples of specific chemical findings from the USGS study:

    * In the Central Valley Aquifer near Modesto, Calif., the USGS found that agricultural and urban development have enabled uranium to move from sediments to water in the upper part of the aquifer. This water can drain down the well when it is not pumping and enter the lower aquifer. When pumping resumes, contaminant concentrations can be temporarily elevated in water pumped from the well.
    * In the Glacial Aquifer in Woodbury, Conn., it was found that the young age of the water throughout the aquifer makes it vulnerable to contamination from man-made compounds. The USGS also found that dry wells used in Woodbury to capture stormwater runoff reroute the potentially contaminated water directly into the aquifer used as a drinking water source. This direct transfer prevents soil and unsaturated sediments near the land surface from filtering out some of the contaminants.
    * In the High Plains Aquifer near York, Neb., the USGS found some contaminants in a public-supply well that seems protected by overlying clay. Nearby irrigation wells have allowed water containing nitrate and volatile organic compounds to leak down from an overlying shallow aquifer into the aquifer that serves as the drinking water source for the public-supply well.
    * In the Floridan Aquifer near Tampa, Fla., it was found that a large percentage of young water and contaminants from a shallow sand aquifer travels quickly along natural conduits until it reaches a supply well in a lower rock aquifer that serves as a drinking water source. Because of these natural conduits, the supply well is vulnerable to the man-made contaminants in the upper aquifer, and the mixing of waters from the two aquifers has caused arsenic concentrations to increase in water reaching the supply well.

The study of public-supply well vulnerability to contamination is one of five national priority topics being addressed by the USGS with their National Water-Quality Assessment (NAWQA) Program. The study began in 2001 with the following general objectives:

   1. Identify the dominant contaminants and sources of those contaminants in public-supply wells in representative water-supply aquifers across the Nation;
   2. Assess the effects of natural processes (such as degradation) and human activities (such as irrigation) on the occurrence of contaminants in public-supply wells in representative aquifers;
   3. Identify the factors that are most important to incorporate into public-supply well vulnerability assessments in different settings and at different spatial scales;
   4. Develop simple methods and models for screening public-supply wells for vulnerability to contamination in unstudied areas and from newly emerging contaminants; and
   5. Increase understanding of the potential effects of water-resource development and management decisions on the quality of water from public-supply wells.

Approximately 35% of the U.S. population receives their drinking water from public groundwater systems. Public drinking water systems are considered public when 25 or more people are connected to the well or there are at least 15 service connections for a minimum 60 days per year.

Pure water is one of the world’s most precious natural resources. With much of India ’s population denied access to safe drinking water, the delivery of safe, convenient and affordable water purification is one of the biggest social and technological challenges in the country today.

Responding to this challenge, Tata Chemicals has unveiled ‘Tata Swach’ - a unique and innovative water purifier. Requiring no energy or running water to operate, an early version of the product first saw the light of day as part of the Tsunami relief efforts. Today, the replaceable filter-based product, which is entirely portable and based on low-cost natural ingredients, delivers safe drinking water at a new market benchmark of Rs.30/- per month for a family of five.

Speaking at the launch, Ratan N Tata, chairman, Tata Sons said, “Safe drinking water is the most basic of human needs. The social cost of water contamination is already enormous and increases every year.  Although today’s announcement is about giving millions more people affordable access to safe water, it is an important step in the long term strategy to find a solution to provide affordable access to safe water for all.”

‘Tata Swach’, is the result of years of collaboration between several Tata companies, including TCS, Tata Chemicals and Titan. Based on an innovative concept developed by the TCS Innovation Labs - TRDDC, the Swach technology combines low-cost ingredients such as rice husk ash with superior nano – technology. The efficiency of the product has been rigorously tested to meet internationally accepted water purification standards.

Water-borne disease is the single greatest threat to global health, with diarrhea, jaundice, typhoid, cholera, polio, and gastroenteritis spread by contaminated water. According to a 2007 United Nations report, half of the world’s hospital beds are occupied by patients suffering from water-borne diseases. In India , such diseases cause more than 1.5 times the deaths caused by AIDS and double the deaths caused by road accidents.

Built around a bulb-like water purifier made of natural elements like rice husk ash impregnated with nano-silver particles, ‘Tata Swach’ is convenient to use. It produces clean and safe water without using electric power or running water, which is often not available in rural areas. The cartridge bulb is packed with a purification medium which has the capability to kill bacteria and disease causing organisms. It can purify up to 3000 litres of water after which the cartridge stops water flow. The water purifier gives the user enough lead time for cartridge replacement. Fourteen patents have been filed for the technology and product.
Commenting on the launch, R Gopalakrishnan, vice chairman, Tata Chemicals said, “Safe drinking water is a basic human right. ‘Tata Swach’ combines technology, performance, convenience and above all affordability to serve this basic human right of millions of consumers.  The Company has made affordability an important part of its innovation efforts. Tata Swach can play its part in the national efforts to reduce water borne diseases.”

S Ramadorai, vice chairman, TCS said “It was the pressing need of people trapped by the effects of natural disasters such as the Tsunami that saw the deployment of one of the earliest versions of this product. A key part was the insight that a natural material like rice husk can be processed to significantly reduce water borne germs and odours when impure water is passed through it. At TCS, we are enormously proud to have played our part in originating this technology which TCL has made into a consumer friendly offering.

Speaking on the superior technology used in developing ‘Tata Swach’, Dr. Murali Sastry, chief scientific officer, Innovation Center and one of topmost nano-scientists in the world said, “It is an enormous privilege to be a part of the development team on a project which has the potential of positively impacting the lives of millions of people globally.”

   An astonishingly small part (less than 2.5%) of the world’s water is freshwater, and of that small part, the vast majority is locked up in ice or snow.That means only a small, fixed amount of freshwater is available for drinking, washing, agriculture, industry, and ecology. Furthermore, most freshwater is far from population centers. Rivers, lakes and groundwater basins are the primary source of the freshwater for human use, but less than one percent of this water is safe to drink. In fact, microbe contaminated water is still the greatest cause of global human sickness and death. Freshwater readily carries disease and toxins, so it must be kept clean and/or treated for it to be potable. Unfortunately, humans continue to pollute water and have not achieved universal access to clean water and sanitation.

    Worldwide, over a billion people do not have access to safe drinking water, and approximately one-third of the world’s population lives under water stress. Water stress occurs when the demand for water exceeds the amount of water available, or when poor water quality restricts its use.Water stress will become increasingly severe as human numbers increase and more waste is discharged into our rivers, lakes, and groundwater. Since water is a vital necessity for all of us to survive, we humans must be very careful about the future availability and quality of freshwater resources for both current and future generations.      
    Water is a shared and finite resource. Our glass of water today may have come from a well, a lake, or the local river, but it has been in many places in the world, and in many forms, such as snow, ice, clouds, rain, ocean water, and groundwater. In fact, it is millions of years old, and this same water will be in use for millions of years more. Driven by energy from the sun, water is in constant motion, cycling through the Earth’s atmosphere, oceans, and continents according to the hydrologic cycle, depicted below in Figure 1.

    It is through the hydrologic cycle that our water resources - our rivers, lakes and groundwater - are continuously replenished. Very little new water is formed, and very little existing water is removed or destroyed; water is used and re-used in nature and by humans. However, we can, and we are, reducing the amount of usable freshwater by polluting it and withdrawing it faster than it can be replenished by rain and snow. While we can also make more freshwater available by desalinating sea water, the process requires large amounts of energy.
      Our Future Water Needs
   A primary goal of this chapter is to present projections to 2150 when the grandchildren of today’s young people will be living on the freshwater that is available to them. We relied mainly on the Global Environmental Outlook 3 and 4 (GEO3 and GEO4) report from the United Nations Environment Programme.
As noted in the UN's Global Environmental Outlook (GEO4) report, scarcity of water and sanitation facilities will increasingly be a major problem for future generations. Currently, per capita availability of freshwater is decreasing and contaminated water is still the greatest environmental cause of human sickness and death. Water resources are being threatened by increased consumption, increased pollution, and increasing population. These threats are likely to become worse during our lifetimes and those of our children.

This article summarizes the general outline and the main results of the book, Environmental History of Water: Global View of Community Water Supply and Sanitationby Petri S. Juuti, Tapio S. Katko, and Heikki S. Vuorinen  published by IWA Publishing. The focus of the book, Environmental History of Water,  is on water, sanitation services and their evolution. Altogether, 34 authors were invited to put together 30 chapters for this multidisciplinary book. The book is divided into four chronological parts; from ancient cultures to the challenges of the 21st century, each part includes an introduction and conclusion written by the editors. The authors represent such disciplines as: the history of technology, the history of public health, public policy, development studies, sociology, engineering and management sciences.
The book emphasizes that the history of water and sanitation services is strongly linked to current water management and policy issues, as well as future implications. Geographically the book consists of local cases from all inhabited continents. The key penetrating themes of the book include population growth, health, water consumption, technological choices and governance. The history of water and sanitation services is strongly linked to current water management and policy issues, as well as future implications. Cross-sectional and historical intra-national and international comparisons have been recognized in many contexts as a valuable method of studying different sectors of human life - including technologies and governance. With regards to the latter, the World Water Development Report 2003 pointed out the extensive problem that: 'Sadly, the tragedy of the water crisis is not simply a result of the lack of water but is, essentially, one of poor water governance.

     Pollution occurs when surface water flows through the domestic waste, industrial waste water, pollutants in the ground, and groundwater seepage.

     Contaminated water is the change in the direction deteriorating the physical properties - chemical - biological water, with the presence of foreign substances in liquid, solid makes the water becomes toxic to human and material. Reduce biodiversity in the country. In terms of transmission speed and scale of the impact of water pollution is more worrying problem of land pollution