Sighting 4010: The Waterford Incident - Project U.F.O. [ Project UFO ]

 First aired on Sunday, May 7, 1978

Rerun on Sunday, September 3, 1978

TV Guide for Rerun on Sunday, September 3, 1978

Side-By-Side

A clip from this episode is shown on The Why Files video at 21:13

My comment thread in this video linked here

And evidently this book was published about it

Aliens in the Forest: The Cisco Grove UFO Encounter