Surf’s up!

Kem Pinpimai’s kayak slid down the wave at the Boise River Park, bounced up and down as if it was in a washing machine, and then flipped over as Pinpimai disappeared in the sparkling white foam.

A second later, Pinpimai rolled the kayak right-side up, his face coming out of the water with a big smile on it.

With the first phase of the Boise River Park completed, there are a lot of big smiles among whitewater boaters.

“This is one of the best I’ve seen,” Pinpimai said. He was lured to Idaho’s whitewater this summer because of the drought in Colorado, and he made a stop at Boise’s park.

“It’s good,” he yelled, plowing right back into the thunderous wave.

After more than a decade of wishing, talking, planning and — finally — construction, the new park is being officially dedicated on Thursday, June 28.

It’s on a portion of the river between Main Street and Veterans Memorial Park, and accessible from a Greenbelt connector path starting at 3400 W. Pleasanton Ave.

It’s now a place where kayakers, rafters and even tubers have been seen bouncing on newly manicured waves.

Nearby is a refurbished Greenbelt section where bicyclists, joggers and strollers stop along the banks of the river to rest, watch kayakers, or just gaze at the water and birds.

A year ago, the river park was the site of an aging irrigation diversion, with hunks of concrete, wood and metal lurking beneath the surface of the river.

The river’s banks were eroded and hid industrial debris. The stretch of river was unfriendly to floaters, and also those who wanted a place to sit along its banks.

Today, the park is a scenic area complete with a new footbridge, paved paths, river-viewing areas, newly planted willows, grass, and a high-tech diversion dam with wave-shaping devices that create fun for surf-crazed whitewater boaters.

Kayakers waited decades for the park to be built as whitewater parks popped up in Golden, Colo., Reno, Spokane and other cities across the country.

Now phase one has been completed in Boise, and it’s making a splash.

A community celebration is planned from 5 to 7 p.m. Thursday; it will honor the civic leaders and donors who helped make it happen. A formal ceremony will begin at 6 p.m. Everyone’s invited to attend and to paddle across Quinn’s Pond.

“Fourteen years ago, a group of volunteers laid the groundwork for this park,” said Boise Mayor David Bieter, announcing the event a few weeks ago. “This month we will see that vision become reality as we gather together to celebrate this wonderful new amenity.”

Phase one, with a cost of about $3.6 million, was funded by the city, the J.A. and Kathryn Albertson Foundation, and private donations from $100 to $250,000, all generated by the volunteer group Friends of the Park.

Construction of the in-river pieces of the park was completed in February, with crews taking advantage of the river’s low winter level. Water was diverted through Quinn’s Pond while crews worked in the dry river bed. The old Thurman Mill Diversion Dam was rebuilt and two wave shapers were installed in the new diversion.

The shapers, with hydraulic flaps and other computerized gizmos, are designed to create a 20-foot-wide wave and a 25-foot secondary wave coming off the diversion for kayakers. The waves are expected to be in use most of the year, depending on river flows.

Jetties were constructed on both sides of the river to make it easier for boaters to get in and out of the water.

The river park is being billed as something for everyone. The Greenbelt between the river and Quinn’s Pond also was rebuilt and landscaped.

A new footbridge was built across the river to provide access between the paths in Garden City and Boise and to connect neighborhoods.

“The park is revitalizing a portion of the river that had been neglected for decades,” said Tom Governale, superintendent of parks for the Boise Parks and Recreation Department.

It is near the site of a former concrete plant and where the river was channelized in the early 1900s. The riparian zone (shoreline brushy areas) and riverbed were considered marginal for fish and wildlife habitat.

The trout habitat has already been restored by the project, Governale said. The local chapter of Trout Unlimited got behind the project because of the improvements in fish and wildlife habitat.

The riverbanks are also being restored and protected from erosion.

Greenbelt users are finding two parallel paths at the wave area. That’s so there won’t be a traffic jam for bicyclists and walkers with kayakers heading to the river.

There’s also a viewpoint for watching the river and boaters.

And it’s not over yet. Phase two of construction on the park will begin in the fall. It will be the Esther Simplot Community Park, which will have a system of ponds connected by streams, viewpoints, fishing docks and gathering places.

The park is being designed as a place for family gatherings, school outings and impromptu gatherings in a natural setting.

A $1 million gift from J.R. and Esther Simplot in January 2003 allowed the parks department to complete the purchase of riverfront property.

The Simplots are footing the bill for planning and construction.

Phase three will be construction of more in-river elements downstream that will create drops and chutes for whitewater boaters. Although the features are designed for whitewater boaters, operators of the wave shapers say the section of the river will be more friendly to casual floaters and tubers.

Costs of planning and construction of phase three are yet to be determined.

Even though the new diversion and wave shapers are providing safer passage on this part of the river, there is still a gnarly concrete-rubble diversion near Veterans Park. It is not friendly for casual floaters.

When that area is cleaned up and improved, the river from below the Americana diversion to the Glenwood Bridge is expected to add another segment for float fishing, kayaking, canoeing, rafting and tubing.

Ideas for the Boise River Recreation Park first started floating around as early as the 1980s. Support for the park came about in the early 2000s during public meetings and hearings.

At the time, proponents pitched improving the river and quality of life in the area, and also economic benefits. They saw new housing springing up in the area, which is being seen as a river community. Ponds and flat-water paddling places in Quinn’s Pond and also in the new Esther Simplot Park would add to the attractiveness of the area, which was an industrial site.

Reports at the time of public hearings showed that more than 150,000 Idahoans, or 16 percent of the population, enjoy paddle sports.

It was reported that in Golden, Colo., a whitewater park on Clear Creek contributed about $2 million annually to the city’s economy. A river recreation park in Vail contributed $1.8 million annually, and a park in Breckenridge $1.4 million.

The Boise River Park has the potential to have a tremendous economic impact, city officials said.

It has already lured kayaker Kem Pinpimai.

Pete Zimowsky: 377-6445, Twitter: @Zimosoutdoors