Stephanie Mills, Tower of Power star at Russian River Jazz and Blues Festival

There’s a simple reason why the Russian River Jazz and Blues Festival - celebrating is 41st year next weekend at Johnson’s Beach in Guerneville - has lasted so long.

Who can resist two lazy days on the river with nonstop live music?

The festival typically draws fans from all over Northern California, who bring low-back chairs and picnics and settle in for a mellow day or two in the sun.

This year’s festival opens Sept. 9 with a day of jazz and headliner Stephanie Mills, the original Dorothy from “The Wiz” on Broadway, and a roster that also includes Stokely, Lenny Williams, Julian Vaughan, Frobeck and West Coast Jam with Richard Elliot, Rick Braun and Norman Brown.

The second day, Sept. 10, is devoted to blues, with Oakland rhythm-and-blues band Tower of Power, famed for its horn section. The rest of the day’s lineup features the Kenny Wayne Shepherd Band, Beth Hart, Con Brio, Southern Avenue and Mitch Woods and His Rocket 88s.

“I like summer festivals and touring,” Mills said by phone from her current tour. “And I like the more intimate houses where I can see people’s faces. I enjoy it all. I’m 60 now and I’m thankful to be doing what I do.”

Her fans can expect her to sing her hit “Home” from “The Wiz,” the hit song from Broadway musical version of “The Wizard of Oz,” later adapted as a film starring Diana Ross as Dorothy.

“The fans would kill me if I didn’t sing that song,” Mills said.

“There was a time when I didn’t want to sing it anymore, but as I matured, I began to appreciate it more. ‘Home’ and ‘The Wiz’ song made history.”

The audience also can expect a lot of classic R&B from Mills, and maybe a little hint of gospel, the music she learned as a girl growing up in Brooklyn and singing at the Cornerstone Baptist Church.

“I come from that background. It was a very strict world,” Mills recalled, and she thinks the discipline and priorities she learned as a child has helped master the demands of a long career.

“I don’t associate with a lot of people in my business,” she said.

“The only time I’m THE Stephanie Mills is when I am onstage. Then I’m ready to do business.” One of the highlights of the festival’s second day will be a set by singer-songwriter Beth Hart, who first won fame with her 1999 single, “L.A. Song (Out of This Town,)” a plaintive, sometimes angry lament about life choices.

Since then, Hart has firmly established herself as a blues artist.

She teamed up with blues guitarist Joe Bonamassa to both perform and record, and then toured with legendary English rock and blues guitarist Jeff Beck in Australia a few years ago. And she continues to branch out musically.

“Working with Joe Bonamassa on our first record, ‘Don’t Explain,’ we weren’t just doing some soul and bluesy stuff. We were doing some jazz,” Hart said by phone during a recent tour stop in Denmark.

“Jazz was in my childhood from my mother, who was like the ultimate femme fatale.”

Hart, 45, was wrapping up a six-week concert tour of Europe, where she has built a strong following, particularly in England, France and Germany.

And she was looking forward to a rest, and a chance to write some songs, at home in Los Angeles before heading north for the Russian River Jazz and Blues Festival.

“I can’t really write when I’m the road,” Hart said.

“I think that whole adrenaline rush you’re getting, and that false sense of security from doing shows, really get in my way. If I’m not humbled out, and on the normal plane of real life, I can’t write.”

Unlike Mills, who always sings her signature song, “Home,” Hart can’t guarantee she’ll perform her own trademark tune, which is “L.A. Song.”

“It’s a totally different set list every night,” Hart said. “When you and your band are challenged every night, that energy comes across to the audience.”

You can reach Staff Writer Dan Taylor at 707-521-5243 or dan.taylor@pressdemocrat.com. On Twitter @danarts