It Is A Reservation Lake
First of all, you must know that this is not your regular lake. Instead, it is a reservation lake. It means that the water has to be healthy and clean to drink at any given time. After all, it goes right to the homes of the locals! We get it if you are even more confused. What do the balls have to do with that?
The Answer Is Complicated
After asking the Los Angeles officials about the 96 million balls over there, they told Derek that it was pretty complicated. However, they were willing to explain it to him in a different way. This was how they ended up bringing Derek to the lake. It was the best way to show him what the balls were doing there.