Moving freshwater around on continents

The gasoline here in Phoenix and Tucson comes in a 6-inch pipeline from Texas. When somebody poked a hole in it between here and Tucson it had to be trucked in. Supplies were very short and the delivered cost was more than $5 per gallon when the retail price was around $3.20. The prices rose to about $4.50 and people screamed but the retailers were losing money on every sale, making it up in cigarette and jerky sales.

A couple weeks later the repairs were done and the prices slowly declined back to normal over a month as they tried to recoup their losses.

Oh yeah? And what happens when those pipelines bust and hundreds of thousands of gallons of dihydrogen monoxide poison the land?

The Central Arizona Project is a canal system that runs from Lake Havasu (elevation a hair over 700’) through the Phoenix area to Tucson (1100’) to Tucson (2400’). From end to end the water passes through 14 pumping stations that lift the water a total of 2900’:

The 456 billion gallons (1.4 million acre feet) of water is lifted by up to 2,900 feet by 14 pumps using 2.5 million MWh of electricity each year, making CAP the largest power user in Arizona.

Admittedly only a fraction of the water goes the whole distance (most of it is used along the way), there are still five pumping stations before the water gets to Phoenix.

Stone him! Heretic!

Yes, very much yes.

Sam Kinison did a bit on moving people to where the food is (with Uhauls).

If it were just that easy. You could also say just have people move to where the floods aren’t, and to where the hurricanes aren’t.

I doubt it. If we used eminent domain to seize all the farm land in the central valley of California that would be about 7,000,000 acres it would have to be paid for at today’s cost which seems to be $10k/acre or about $70b.

Then we’d have to convince all of those millionaires to spend their millions to buy land on the Mississippi area or in Northern Idaho based on where that map had water sustainable farming. We’d also have to have all of the labor and associated business to move too. The million people in California picking up and moving would mess with the California economy and wherever they settled would see a huge population influx and cause huge problems in their economy.

In the long term your solution is the best one but it would be massively damaging in the short term and probably destroy the political party that carried out the idea.

Why are you positing some sort of forced paid removal?

People moved out there for reasons: they wanted lots of sunshine, and assumed that all the water they wanted would be provided for cheap. If what they assumed were the facts behind those reasons change, they will then find reason to move elsewhere.

It’s true that it’s better if this happens gradually instead of all at once; but nobody said otherwise.

People moved there during the dustbowl. Aside from the government intervening they will stay there until the next dust bowl and will expect their politicians to keep them farming long past the viability point. Water will be warred over and stolen long before those farmers pack up and move voluntarily.

What about splitting the water at the source then piping hydrogen. You could regain some of the energy by burning it at the destination, perhaps to make electricity. The output would be pure water. You could even use some of it to power the pumps along the pipeline.
Would this be more or less energy efficient?

Piping masses of hydrogen across the country? What could possibly go wrong?

Stranger

We pipe natural gas. Nothing is 100% safe.

I’ll leave the question of energy efficiency to someone else, but you can be damn sure it will be less water efficient. You’d be cannibalizing your water supply at Point A to move it to Point B, and then consuming even more water from Point A to turn it into fuel to move it to Point B.

I was thinking primarily tunneling and digging canals over a period of a hundred years or even more something that would last forever

Natural gas tends to stay readily confined in normal pressurized systems, and if dry and oxygen-free doesn’t really tend to cause corrosion internal to pipes and tankage. Hydrogen gas leaks from the tiniest crack or misfit joint, causes hydrogen embrittlement, and is also extremely low density unless compressed to cryogenic liquid temperatures. Having worked with hydrogen as a fuel and dealt with the multitude of safety issues, I feel pretty confident in saying that a nationwide network of hydrogen pipelines would be a catastrophe in the making.

It would be spectacularly inefficient; the energy cost of a theoretically 100% efficient electrolyser would be almost 40 kilowatt-hours per kilogram of hydrogen, which would be 8.94 kg of water. Even if you are assuming you could recover all of this energy at the other end through combustion with complete thermodynamic recovery (impossible, of course, says Carnot), you are still having to produce this energy at the source and with sufficient power to deliver large volumes of water to the end user, so the source gets no benefit or recovery. Desalination of sea water, while also enormously energy-intensive, would still be more feasible than piping hydrogen cross-country.

Stranger

You could use solar, wind, or nuclear to split the water.

Regarding desalination, you’d still have to somehow deliver that water to non-coastal regions.

There’d be no net energy gain but the point isn’t an energy gain. The point is transporting water as energy efficiently as possible.

Uh, how about using clouds.

“Sometimes the old ways are the best…”

Stranger

For moving volumes of water there are two sciences/technologies: gravity and evaporation. Anything else is uneconomic, unless it’s Perrier.

The places that have the water don’t have the weather to grow the crops. The kind of Mediterranean cash crops they grow in California - almonds, grapes - aren’t going to grow nearly as well around the Great Lakes.