As someone who knows nothing about canals (or what they are even used for), anyone want to explain why they are used, why they are dumb, and what we should do instead?
An irrigation canal like this is a big ditch to move water from a river to near farm fields. Without the extra water taken from the river, there wouldn't be enough water in the soil for crops to grow in the area.
Being a big ditch open to the sky, the hot sun and dry air make a bunch of the irrigation water evaporate before it even gets to the field. So we went to all the effort of taking water out of the river just to waste it humidifying the nearby air.
Why did we do it in the first place? Because it's way easier and cheaper to dig a ditch than to lay a big pipe, and I don't know if the US had any other water-delivery tech at the right scale when these were built.
The US has lots of land that doesn't require irrigation, but also lots of land that can grow crops if irrigated. Some of that land in California is some of the best farmland in the whole country, growing things that prefer California's Mediterranean climate (similar to parts of Australia's southwest coast).
We have the technology and have had it for a while. But we don't have the laws and habits of dry countries so US water laws are a wasteful mess.
As someone who knows nothing about canals (or what they are even used for), anyone want to explain why they are used, why they are dumb, and what we should do instead?
An irrigation canal like this is a big ditch to move water from a river to near farm fields. Without the extra water taken from the river, there wouldn't be enough water in the soil for crops to grow in the area.
Being a big ditch open to the sky, the hot sun and dry air make a bunch of the irrigation water evaporate before it even gets to the field. So we went to all the effort of taking water out of the river just to waste it humidifying the nearby air.
Why did we do it in the first place? Because it's way easier and cheaper to dig a ditch than to lay a big pipe, and I don't know if the US had any other water-delivery tech at the right scale when these were built.
Are there not enough areas of the US that get rainfall suitable for growing the needed food?
The US has lots of land that doesn't require irrigation, but also lots of land that can grow crops if irrigated. Some of that land in California is some of the best farmland in the whole country, growing things that prefer California's Mediterranean climate (similar to parts of Australia's southwest coast).
We have the technology and have had it for a while. But we don't have the laws and habits of dry countries so US water laws are a wasteful mess.