system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5 Why can't we pipe water to southwest US?

We pipeline oil from Canada to Texas, why can't we pipeline water from the Great lakes to the south?

Edit: thank you all who replied, I've gathered that it is technically possible, but would come with a huge amount of legal, environmental, and practical issues due to the amount of water that would actually be needed. It sounds like there are far more practical solutions available if the need became dire enough.
gpt
Just the extreme cost.

So, there's costs involved to move things in a pipeline. And it's not hard to recoup those costs with oil. Right now, the market price for a gallon of crude oil is about $2.65.

The market price for a gallon of water is less than a penny. In fact, a penny would get you about six gallons of water at wholesale prices.

On average, it costs about $5/barrel to move oil in a pipeline. Of course this will depend on distance, but it's a convenient number. That's about 12 cents per gallon.

The cost of pipeline transport for oil is about 4% of the cost of the oil. If we had that cost for transporting water, it would raise the cost of the water by 7200%.