AFAIK it's been available since the 1870s but after the 20s they clamped down a lot harder on ensuring you were actually irrigating it and had agricultural plans.
I'm not sure if the BLM has relaxed their discretion under Trump.
Do you think laws go away just because they're old?
The Colorado River compact came into effect in 1922 and I'm almost surprised literal fist fights haven't erupted over it during the modern negotiations.
I’m no lawyer, but according to my perusing (sourced directly from the BLM), the 1877 Desert Land Act is very much obsolete.
The age of a law does not matter with regards to its validity, you are pedantically correct. But it very much matters to its relevancy, which was my argument. Laws regarding horse traffic in Manhattan may still be valid, but a lot less relevant than they were hundreds of years ago - assuming they haven’t been repealed.
Regarding the “Colorado River compact”, I would say my qualifier of “quite niche” is important. Ownership and water rights over the second largest watershed in the US by affected population is far from “niche”.
On the other hand, how settlers can claim public land in the desert (which happens incredibly rarely now, by design) is quite niche.
Even if you presume it's obsolete, the fact remains the land was distributed under a model where it had to be claimed, developed, and irrigated for agriculture. The water distribution and well systems alone required for agriculture far surpass use for residential purposes, for example, but once you have wells and irrigation suitable (not cheap in the desert, and also valuable) for agriculture it may be more economical to just keep going with it. The momentum of that remains and the economic incentives aligned with those policy choices remain with us as to part of the reason why desert land is used as it is. The first developed use of land can have a lot of influence on what happens next, it's quite different from starting from an undeveloped state with pure free market forces on development.