Swimming pond water is blue, is that ok?

Question

My friend just got a pond out on his property the other day. He was getting some land and dirt cleared/dug out and came across an old mine that was filled with water. Well he decided to make a HUGE swimming hole/pond.

It looks fantastic and the water is a very blue color, sort of between a light and medium blue color. When swimming the water gets brown from the dirt but goes back to the blue when it's still.

Is that water safe to swim in. My fiance' said he thought when water is that color it was unsafe to swim in. Is that true and also what causes the water to be that color?

Thanks for any answers, we are just really curious.

Answer 1

It sounds to me that it is just the reflection of the sky making it appear blue.

Answer 2

my dad       said when he was a kid he used to swim in ponds all the time and he is 80 now did not hurt him so i think it will be fine