Water on Tap M ost of us take water for granted We turn on the faucet when we want a drink We have a bath or shower every day and we turn on machines to wash our clothes or dishes We simply expect water to be there whenever we want it Imagine what would happen if you turned on the faucet and nothing happened Suppose your water supply just ran out You would have to gather rainwater to wash with and join long lines of people waiting for fresh water to drink Many farms in developed countries use large quantities of water to irrigate their crops Much of this is wasted in runoff and evaporation As the population of the world increases the worldwide demand for water is growing It is not just drinking water that the world needs it is water for agriculture and manufacturing industries Did you know that it takes 37 gallons 140 l of water to produce one cup of coffee Or 792 gallons 3,000 l to make a hamburger and 2,100 gallons 8,000 l to create a pair of leather shoes All of these processes require enormous amounts of water to grow crops feed cows or produce leather 4
In dry places such as parts of Africa many homes do not have running water These people in Zambia have to travel long distances every day to fetch water for their families Unfortunately water is not distributed evenly across the world In many countries where water is plentiful people often waste it In other countries many people do not have enough water Water is a valuable global resource and everyone should help look after it by using it carefully and wasting less Families in New Jersey enjoy a day out at a water theme park People in developed parts of the world rarely suffer water shortages and may take water for granted
The Water Cycle T he water on the Earth is always on the move it is constantly being recycled Water moves between rivers and land the oceans and the atmosphere This continuous movement of water is called the water cycle No Beginning or End The water cycle is a true cycle which means there is no beginning or end The cycle is driven by the Sun which heats the water in the oceans and the surface water on the land The water evaporates and becomes water vapor As the water vapor rises it becomes cooler and condenses to form clouds Air currents move the clouds around the world and eventually the water falls back to the surface as rain snow sleet or hail Water that falls on land either soaks in and becomes groundwater or finds its way back into rivers and lakes Some of it falls as snow on mountains or at the poles It may stay frozen here for thousands of years before melting and rejoining the cycle This diagram shows how the water cycle works 6
The water cycle can clearly be seen in action in a rain forest where it rains every day Trees absorb water through their roots and give off moisture from their leaves Clouds gather above the tree tops eventually bringing more rain some of which reaches the rivers Ancient Water The fact that Earth’s water is always recycled means there is never any new water added to the cycle nor is any ever lost The water in the glass you drank today may have fallen as rain on the other side of the world last year or could have been part of the Atlantic Ocean when Columbus sailed to America in 1492 Taking Water Out Human actions alter the water cycle by temporarily removing water from it Water is taken out for farming industry power stations hydroelectric power or hydropower and for domestic use Although the water finds its way back into the water cycle eventually the amount taken out increases every year It is also not replaced instantly When water is pumped from groundwater it can take thousands of years for water to replenish these reserves How can you help Use a watering can to water your yard rather than a hose or sprinkler Lawn sprinklers use as much water in half an hour as an average family of four does in a day 7
