For those curious, here's one useful source talking about the water usage

https://www.vox.com/the-highlight/23655640/colorado-river-water-alfalfa-dairy-beef-meat

For some more numbers. Per liter, dairy milk requires 628.2 L of freshwater vs almond milk requiring 371.46 L of freshwater. And if you use something like oat milk instead that gets you to 48.24 L

https://ourworldindata.org/environmental-impact-milks