This a beautiful river. You can go further downstream of it to hike on a trail to be able to swim in the river (small fee). Definitely worth it.
Was there in December! Very beautiful, and a beautiful hike despite the traffic.
For those who may not know, the water gets its blue color from the mixing of two colorless rivers upstream - one carries aluminosilicates, and the other has high acidity. When combined, the drop in pH causes the aluminosilicates to form spherical aggregates that scatter light in a way that lets us see the turquoise color (an example of Mie scattering)!