Learn about the devastation caused by water pollution and the need for clean water in this free online course.

Water is a vital resource in short supply and unevenly distributed on our planet. Less than one percent of all the water on Earth is clean and easily accessible freshwater and about two billion people drink contaminated water. Discover the natural and human water cycles, where humans intercept, use and dispose of water at different stages of the natural process. Following this, we define ‘pollution’ and explore its various types and sources. Water pollution comes mainly from the following sectors of society: agriculture, industry, energy production and domestic use. Households are the primary source of sewage and also dispose of a variety of toxic substances. Plastics are another source of water pollution, from clothing micro-fibres to plastic rubbish to large fishing nets, which are either eaten by mistake or entangled with aquatic life.

Explore water usage in various sectors and the water used for a single product, such as a cotton t-shirt. Did you know that agriculture uses 70% of the world’s freshwater? Additionally, to manufacture a t-shirt, you would need a whopping 2700 litres of water. We also look at individual water-use and make a rough comparison between countries. We will learn about a ‘water footprint’ that includes the water used to make the products we buy and services we use, in addition to our direct use for washing. The section finishes with the prediction of increased water scarcity by 2050, due primarily to increasing demand, unless we take significant measures to use water more efficiently and reduce our contribution to water pollution.

Finally, we look at ways to conserve water and improve water quality. Individuals, businesses, NGOs and governments will need to drive the efforts required. Agriculture will need to adopt more conservative and targeted irrigation strategies, transition as much as possible to biological pest control methods and targeted use of natural fertilisers and better contain and reuse animal waste. Examples exist in the industry of closed-loop systems, where waste is treated and reused without discharging into the ground and waterways. There are also natural, compostable materials that you can use widely and safely. Our energy system is undergoing a welcome transition towards greater use of cleaner, renewable energy sources and this will need to be encouraged and accelerated. Households, or consumers, will need to be more aware of the environmental impact of their purchases and be encouraged to make environmentally friendly choices. As far as plastics are concerned, less use and more compostable and safe, reusable alternatives are required.