There ARE a race of super beavers in Idaho. Soon all mankind will be subservient to the Great King Beaver (BTW: King Beaver was the original name for the DHC 3… better known as the otter). It’s still largely the way it looks in the film, as might be expected for an area about the size of England with only 1.3 million people.
Oddly, I just returned from a tour of a school chum’s recently acquired 45 acre Idaho back country property. Lovely place….but hardly user friendly, you have to dig a well, put in a septic system, use solar power or install water turbines in the creek. Of course, first you have to grade a road to the home site. Not exactly pre-fab suburbia.

To answer your question…for those of you who haven’t watched the film…spoiler alert….
The state developed crates with a door that would spring open on contact.
The parachutes were modified war surplus units which were then inexpensive and plentiful.

Nowadays, I suppose they’d use helicopters….so you’d likely have bearers flying around in squirrels.