UNIT10

1	Thirty years ago, Lake Ponkapog in Hartwell, New Jersey, was full of life.  Many birds and animals lived beside the water, which was full of fish.  Now there are few birds, animals, and fish.  The lake water is polluted.  It is a dirty brown color, and it is filled with strange plants.
2	How did this happen?  First, we must think about how water gets into Lake Ponkapog.  When it rains, water comes into the lake from all around.  In the past, there were forests all around Lake Ponkapog, so the rain water was clean.
3	Now there are many homes on the lake shore.  People often use chemicals in their gardens to grow vegetables and kill insects.  When it rains, the rain water carries these chemicals into the lake.  Other chemicals enter the water from factories near the lake.  These chemicals pollute the water and kill the animal life.
4	Boats on the lake are also a problem.  Lake Ponkapog is a popular place for motorboats and jet-skis.  But oil and gas from boats and jet-skis also pollute the lake.
5	There is still another problem at the lake \\ exotic plants.  These plants come from other countries.  They have no natural enemies here, and they grow very quickly.  In a short time, they can fill up a lake.  Then there is no room for other plants.  The other plants normally growing in the lake die.  These other plants gave many animals and fish their food or their homes.  So now those animals and fish also die.
6	People in Hartwell are worried.  They love their lake and want to save it.  Will it be possible?  A clean lake must have clean rain water going into it.  Clean rain water is possible only if people are more careful about chemicals at home and at work.  They must also be more careful about gas and oil and other chemicals that flow into the ground.  And they must stop using motorboats and jet-skis on the lake.
7	All this may cause many changes in the lives of the people living near the lake.  And then, scientists need to find a way to stop the spread of exotic plants.  Only then can Lake Ponkapog be a beautiful and clean lake again.
