portfolio 6: (summarized the article related to 14 grand challenges of engineering)

Today, the availability of water for drinking and other uses is a critical problem in many areas of the world. Lack of clean water is responsible for more deaths in the world than war. In some countries, half the population does not have access to safe drinking water, and hence is afflicted with poor health. By some estimates, each day nearly 5000 children worldwide die from diarrhea-related diseases, a toll that would drop dramatically if sufficient water for sanitation was available.
Indeed, water is available in abundance in the world. It is just not always located where it is needed. For example, Canada has plenty of water, far more than its people need, while the Middle East and northern Africa suffer from perpetual shortages. Otherwise, in some developing countries, water supplies are contaminated not only by the people discharging toxic contaminants, but also by arsenic and other naturally poisonous pollutants found in groundwater aquifers. For the healthy, sustainable future for the planet, developing methods of ensuring adequate water supplies pose engineering challenges of the first magnitude.
In fact, there are two methods used to supply water to regions in need. The first one is diverting the flow of water from regions where it is plentiful to where it is scarce. Such diversion projects provide some short-term relief, but not appear practical as widespread, long-term, ecologically sound solutions, and this method generally will not be able to meet agricultural needs. The second is desalination which is extracting the salt from seawater. However, desalination plants are expensive to build and require lots of energy to operate, making desalination suitable mainly for seaside cities in rich countries. Therefore, new technologies with economical viability will be needed.
T o deal with the problem of providing clean water, many technologies have been developing. For instance, technologies are being developed to improve recycling of wastewater and sewage treatment so that water can be used for nonpersonal uses such as irrigation or industrial purposes. Some current projects are striving to produce inexpensive distillation units that can remove contaminants from any water source. A unit smaller than a dishwasher could provide daily clean water for 100 people.
In general, such approaches will help to address the very real problem of inequitable distribution of water resources. Even within a given country, clean, cheap water may be available to the rich while the poor have to seek out supplies, at higher costs, from intermediary providers or unsafe natural sources. Technological solutions to the world’s water problems must be implemented within systems that recognize and address these inequities.