A good wave lifts all boats.

It also lifts the businesses that rent those crafts and the spirits of people who play in them.

The waves at Boise River Park even boosts sales of ice cream sandwiches.

“It’s bringing a ton of business to us,” said Colton Kerkman, who sells refreshments at the Yak Shack a few hundred feet from the whitewater park.

Since the city dedicated the park June 28, Kerkman said, the Yak Shack’s sales have doubled.

Boise River Park’s waves have been a hit with the Treasure Valley’s water sports community. As of Friday afternoon, the park’s Facebook page had 1,150 “likes.” Kayakers, surfers, body boarders and other wave junkies used the page to rave about their experiences.

But on any given afternoon and evening, people watching, playing and otherwise standing on the side of the river outnumber the people in the water by a wide margin.

That comes as no surprise to city officials and private fundraisers who designed the park. After conversations with cities throughout the country that are home to river parks, they expected to see more pedestrians than wave users.

It’s why they added wide standing areas to the Boise River Greenbelt directly between the waves and Quinn’s Pond.

“I’m not so much surprised by the number of people,” said Tom Governale, Boise’s superintendent of parks. “I’m more surprised by how consistent it is. I expected large crowds. I didn’t expect them throughout the day.”

Governale said he’s been impressed by the variety of activities that people who use the park pursue. Besides boaters and surfers, he said, he’s seen triathletes-in-training show up.

One of the main reasons for building the $3.7 million park was to enhance the Greenbelt’s capacity as an economic development tool, Governale said. On that level, it appears to have been a success.

Pamela Tucker, who’s worked at Idaho River Sports just east of Quinn’s Pond for five years, said she’s never seen the store busier. Mostly, she said, that’s thanks to increased rentals of kayaks, stand-up paddle boards and other toys customers use to play on the park’s waves.

Governale said a broad swath of Boise hotels, gas stations, restaurants and other businesses will benefit as the park’s reputation grows.

“We’ve just increased our reputation as a whitewater capital,” he said.

The idea for the river park first came about in the late 1990s, but a twisting, complicated series of events stood between it and reality. There were delays and delicate negotiations with irrigators who divert water from the river just upstream of the wave-shapers.

The fact that the park is not only open, but thriving, is “a huge vindication because there was more than one person publicly saying, ‘This isn’t going to happen,’ ” said Beth Markley, campaign counsel for Boise Friends of the Park, a group founded with the purpose of raising money for the river park.

Some in the boating community second-guessed the park’s design, Markley said.

Whether it’s because the river park’s open or because the hot weather drives people to water, traffic at Quinn’s Pond seems to have picked up as well. Annie Chamberlain of Boise said having the pond a few feet from the waves makes it possible to bring her whole family out.

While her 14-year-old son watches her two young children playing in the pond, Chamberlain takes a few runs at the waves in her playboat — a short version of a kayak. After a while, she trades places with her son so he can play on the waves, she said.

Chamberlain said the river park’s popularity doesn’t surprise her at all.

“People in Boise, they just get out,” she said.

A quasi-culture has emerged at the park. The waves attract an older, more-equipped crowd, while the pond is a popular hangout spot for teenagers, said Heather Ragsdale, a 20-year-old who lives in Boise.

Ragsdale’s friend, Aliccia Morentin, 17, said she visited the pond almost every day last month.

“I run into people here I haven’t seen in three years,” Morentin said.

But Governale sees age groups mixing, too. Watching the wave junkies play, he’s gained an appreciation for just how social river rats can be. If they’re not in the water, he said, they’re talking about the water, their boats, their techniques — just talking.

“You’re getting crossed generations and they’re hanging out with each other, so there’s some real social benefits there as well,” Governale said.

With this notch on their belts, Boise Friends of the Park and city Parks and Recreation officials have shifted their focus to expanding the project.

Markley said her group is planning to install a parking area and bathrooms at the planned Esther Simplot Park nearby.

Governale said the city hopes to build the river park’s second phase, which would include more play waves, by 2015.

He admits the river park in its current state might grow so popular that the crowd consistently chokes traffic passing through on the Greenbelt. Already, he said, “There are days when it gets a little iffy.”

But he’s not too worried about it.

“That’s a good problem to have,” he said.

Sven Berg: 377-6275