After four summers of running a lending library on a floating raft, artist Sarah Peters has learned a few things:

• Slide the books into plastic sleeves to keep them dry, but keep the sleeve tops open to avoid condensation.

• Wipe the sunscreen off your hands before handling the books, to avoid grease stains.

• Beware the wind, which can whisk your whole collection overboard.

Now in its fifth year (out of six — they took last summer off), the Floating Library returns to Lake Phalen in St. Paul for three weekends, beginning Saturday. Boaters can glide up to the raft, browse the books, borrow a few, and then return them either to the raft or to a box on land.

The library first launched in 2013 on Cedar Lake in Minneapolis, where it was so far out in the water it was difficult to get to.

“It was like an hour’s paddle from the boat rental,” Peters said. “People would discover it in the wild.”

It returned to Cedar Lake the next year, moved to St. Anthony’s Silver Lake in Silverwood Park in 2015 and then to Phalen in 2016. It has also traveled — to Winona, and to Echo Park Lake in Los Angeles.

It had never been Peters’ plan to continue the library for so many years.

“Plan? Who plans? Who plans anything anymore?” she said, only half-kidding. “One of the joys of being an independent artist is that I don’t have a strategic plan. I don’t have a board to consult with. It’s just as the winds, the funding, and the energy dictate.”

The library is a custom-designed raft built of wood and kept afloat with pontoon-like 55-gallon drums that were once used to supply the University of Minnesota with hand soap.

The books are donated by artists from around the country, and some from overseas. Peters puts out the call in the spring and artists submit ideas.

“It’s a unique way for their work to be seen,” she said.

While these are handmade artist books, “most of the work is not super-duper fine press,” she said. “These aren’t books that come in a handmade box with the finest of onionskin papers. There’s a lot of ’zines and comics and some pieces that are beautifully constructed out of expensive paper. It runs the gamut.

“Every year I’m amazed at how many people submit their work for possible water damage.”

This year Peters — who is also co-director of the summer festival Northern Spark — is adding a public art component.

“Waves Unfolding: A Paper Memorial” by St. Paul artist Anh-Hoa Thi Nguyen will commemorate lives lost during the exodus of Vietnamese refugees between 1954 and 1992.

On the first two Sundays, visitors to the lake can contribute to Nguyen’s project by taking part in workshops on the construction of origami paper boats. The fleet of 1,000 paper boats will be ceremonially launched on the final Sunday.

The Floating Library (thefloatinglibrary.org) has been funded over the years by a variety of grants.

“I rely on the amazing support from our public sources here in Minnesota,” Peters said, including a Community Arts Grant from the Metropolitan Regional Arts Council, a State Arts Board Initiative Grant and a Knight Arts Challenge Grant.

“It’s the only reason it’s happening,” she said.

But happening it is — a project that brings together some of the best things about summer: sunshine, water, community and books.

Because you never know, when you’re out for a paddle, when you might be seized with a need for something to read.