I seem to remember my kids elementary school class going over the fact that the earth has the exact same amount of water that it always has had. It recycles naturally. I remember this because she was amazed by the fact that the same water resources that were here in the times of dinosaurs were here today. I may be simplifying this, but I do remember her class studying it.
Yes, we have the same amount of water but not necesarily as clean.
Actually, we are losing water (or rather, the earth's water is gradually becoming inaccessible). Millions of gallons is subducted into seafloor trenches every year, and much of it never resurfaces through volcanoes.
In actuality, there is MORE than there used to be.
Scientist have found that smal comets (iceballs) pelt the Earth every day, every minute, every second, to the tune of hundreds of tons of water a day.
Such a conclusion does not count the water I have in my storage room. I'm holding out on the system. My stored water can't evaporate or enter into any biological processing/recycling system until I open it and use it.
Imagine if everyone in the world kept 50 or so gallons of water in storage--the world would dry up!!
The only solution to this is to eliminate all you other water hoarders. I get to keep mine however, because I'm a superior person. ;^)