We all know that the people of the world do not have enough to eat. But are we aware
of the fact that they do not have enough to drink either? This will sound very
strange because three-fourths of the earth surface is covered with water. But
about ninety-seven per cent of it is salty water. So, man can drink only three
percent of the total water on the earth’s surface. This water is fresh and it
comes from various sources. But a part of this water is not usable because it
is in the form of ice-bergs and glaciers. Even worse, some of it is too
polluter to be drunk.
However, this small amount of fresh water, which is constantly being replenished by rainfall, is serving our purpose just somehow. But our need for water is increasing almost everyday. If we take immediate steps to deal with this problem, we shall be able to avoid a severe worldwide water shortage in the near future. With the expansion of industries, our need for ordinary water is also increasing rapidly. One example will make the whole thing clear. It takes about 91,000 liters of water to produce a single ton of steel.
Wasting of precious water must be stopped. One of
the first ways to achieve it is to develop ways of re-using water Experiments
have already been done in this field, but only on a small scale. The systems
that have been worked out resemble those used in a space-craft.
Raiyan has always been keen to visit interesting
places. He goes to various places every year with his parents. This year, he
has decided to avail himself of a couple of
tours offered by the Parjatan Corporation to spots in and around Dhaka.
With this end in view. Raiyan went to the office of Parjatan Corporation and collected all the
information regarding the trip. He come to know about the cost and the schedules
of the trips. He also knew about the food and entertainment facilities offered
by the organigers.
Only three percent of the surface water isdrinkable. But a part of it is not usable because of its form of ice-bergs and glaciers. Besides, some of this water is
so polluted that we cannot drink it. So, to meet the increasing demand of fresh
water and to face a worldwide water crisis, we must come forward. We must stop
wastage of water and develop ways of rusing water.
