THE SAME RIVER TWICE

(two stars)

Running time: 78 minutes. Not rated (nudity). At the Film Forum, Houston Street, west of Sixth Avenue. Through Sept. 23.

I N 1978, Robb Moss took 17 friends on a rafting trip through the Grand Canyon. But this wasn’t your ordinary rafting: The young hippies on this trip spent most of the journey in the nude.

Fast-forward to today, when five of the rafters are interviewed by Moss – who has taught filmmaking at Harvard for 15 years – in his documentary “The Same River Twice.”

For the most part, they’re fully clothed, middle-class citizens who have maintaned their youthful idealism.

They’re married and/or divorced, with kids and respectable jobs. One is the mayor of Ashland, Ore. Another is director of a small-town mental hospital.

Only one, Jim, still rides the river (except for six months when “he tried to be a dentist”).

Cutting between new footage and old 16mm film he took of his friends letting it all hang out on the Colorado River, Moss allows the five to tell their stories.

“Back then, you didn’t need a good reason to take off your clothes – you needed a good reason to keep them on,” one offers.

Nicely put, although “The Same River Twice” is (except for the naked bodies) only marginally interesting.

Do we really care about these people?

It would make a worthy entry on public TV, but just doesn’t have the heft for a theatrical release.