This gem was written by E. B. White in 1937 as a story in the New Yorker, reflecting the unintended consequences of government action. The 8-minute animated film was directed by Yvon Mailette in 1973, and the amazing part of the story is that E. B. White did the narration!
The reel was in an educational setting, and the liner notes suggest how it can be used in Creative Writing and Film study. It gives a great summary, and there is a fabulous 2012 blog post about it at the National Film Board of Canada, which produced it.
Another piece called it a "forgotten story about the tyranny of good intentions."
Of particular note here is that I have been unable to find any online source for a digitized version... there are lots of stories about this, but the footage itself is obscure (with one on the 'tube locked as private). A bit of history, which other than the usual red fade (accurately shown in the scan) appears to be in very good shape. 7-inch reel in plastic case with Dymo label title on edge.
The NFB blog closes with this:
The Family That Dwelt Apart remains fresh and lively. The story, even though it is set in the 1930s, is still topical. The wonderful narration is a perfect complement to the zany animation (not to mention the folksy music) and the themes are still pertinent today. As the old saying goes, the road to hell is paved with good intentions. If this had been a documentary, it would be a tragedy. As an animated fiction film, it remains a very black comedy. I invite you to watch it and be amused.