In the West you can have chilled water all day - - cheap, easily.
A wet sock not only provides evaporative cooling, but blocks the sun.
My experience is that water is up to 40 degrees cooler - i.e. chilled.
If you keep the sock wet. It's worth it.
Insulated bottles leave you about 10 ounces and cost a bundle.
Camelback water tastes like hot plastic.
I've toured with ice-cold water for 30+ years.