Water is EXTREMELY IMPORTANT to our lives. Without it, the human race would vanish. People first got water from lakes, oceans, rivers, etc. They even washed their clothes in the lakes, oceans, and rivers (It's better than nothing, trust me) Then we go up a few years! into the time travel machine!
Now we are farther in time. Try and imagine getting water only from a well all the time. The wells filled up with the rain water when storms passed through. Then people started using pump-like things. We are now going back to the present! hold on!
We are now back in the present! You see people getting water from sinks, water fountains, water bottles, etc. That is because the invention of the sewers and the water pipe! Without those, we would still be in the past! That is the importance of Water.