Is anamolus behavior of water at 4 degree Celsius so that aquatic life can survive design or evolution?

It's not 'so that' anything. Things evolved in certain ways because there was a context concerning the anomalous behaviour of water (not just its greatest density being at 4 degrees C, but also the fact that it is lighter as a solid than as liquid - life as we know wouldn't be possible if ice sank to the bottom!).