Except it’s not really white, unless it’s frozen and snow covered. And given that it is 2234m above sea level (over 7000ft) that happens quite frequently.
If you happen to be staying in the Bernina area of Switzerland, you might want to travel along the Bernina Pass and take a look at this little lake. It’s about 1.5 square km, which is less than a square mile, so there’s not masses of walking to get round it, but expect to do some clambering.
The milky green colour of the lake is caused by the high degree of oxygen in the water that has melted from the two glaciers.