Safe Water, A Global Concern

Each year, 1.4 million people around the world die from inadequate and unsafe water, and this number is expected to rise. People living in Saharan Africa and parts of Asia are impacted the most heavily.

Safe water

Safe water is a global concern. By 2050, it is estimated that nearly 3 billion people worldwide will suffer from either insufficient water supplies or lack access to safe water. Safe water is water that is free of microbes, travels through pipes that keep the water clean, and is stored in sanitary containers or water treatment facilities. The most important aspect of safe water is the microbe content. Microbes carried by drinking water can cause serious epidemics such as cholera and hepatitis as well as many other diarrheal diseases. Water can also be carcinogenic if it has high concentrations of certain chemicals, such as nitrates and heavy metals. Nitrates in water can interfere with the body's ability to absorb oxygen. High arsenic levels in water can lead to the occurrence of cancer. Too much fluoride in water can cause a crippling disease called skeletal fluorosis.

In North America and Western Europe, water travels to a treatment facility before it can be distributed through pipes to be used for drinking directly from the faucet. In the United States, water quality is monitored according to the Safe Water Drinking Act (SWDA), which was passed by Congress in 1974. The SWDA regulates every aspect of the public drinking water supply, from protecting the sources of water in springs and rivers, to measuring the levels of 80 different substances that can be found in water, and regulating how water is delivered through a system of pipes to individual homes.

Water shortages

Today, over 16 percent of the world's people lacks access to safe water, as shown in Figure 1. Experts in global water supplies believe that there is enough fresh water on Earth to meet the needs of every person. The struggle lies in making clean water accessible and affordable for every consumer. In some areas, seasonal, geographical and hydrological factors can cause springs to dry up periodically.

Also, sometimes the demand for water in an area is not well managed. For example, one group might use more water than another, leaving some areas with insufficient and unequal supplies. Often, local supplies have not kept pace with population growth, and the inadequate equipment and delivery subsystems fail, leaving communities with an unreliable, and at times, unhealthy, source of drinking water.

The United Nations World Health Organization (WHO) has targeted safe water as part of a decade-long mission from 2005 to 2015. To make safe water available to more people, the United Nations WHO is focusing upon global water issues on four levels: treating water and keeping it free of microbes and toxic chemicals (the critical parameters that WHO targets for on-site monitoring are: the presence of e coli, the amount of chloride present and the pH in places where the water is chlorinated, and also turbidity), managing drinking water and irrigation water so that it carries water safely, changing people's habits such as how they wash their hands, and managing natural resources and ecosystems.

Teacher's Edition for Feature on Safe Water

Purpose

Students will relate what they learned about water resources to a global public health issue.

Background

Water is considered unsafe if it contains high levels of microbes, or certain chemicals such as arsenic and nitrates. Much of the global disease burden is related to inadequate access to safe water, and the people who suffer the most are children.

Teaching Strategies

The United Nations World Health Organization has implemented four initiatives to address the issue of safe water, which are outlined in the last paragraph of the feature. Divide the class into four teams. Assign each team to one of the four WHO initiatives: Team 1: Water treatment; Team 2: Managing and maintaining drinking water pipes; Team 3: Habits and hygiene; and Team 4: Managing natural resources and ecosystems. Have each team discuss how their initiative can help ensure safe and adequate water supplies around the world. Sample answers: Team 1: Water can be chlorinated and filtered to remove microbes and impurities. Water can be tested for the presence of harmful chemicals. Team 2: Pipelines should be maintained so that they do not allow unsafe water to infiltrate into drinking water. Pipelines should be placed far from wastewater lines carrying septic material. Team 3: People can learn to store water in clean, closed containers, and to dispose of their waste far from drinking water supplies. Team 4: The water table in an aquifer needs to be monitored to prevent groundwater resources from being depleted faster than they are naturally replenished.