North Idaho's Silverwood Theme Park expects another record-breaking year in 2011, with season pass sales already up by 4 percent from last year, says Silverwood spokeswoman Nancy DiGiammarco.

Following a record of more than 628,000 guests in 2010, Silverwood is projecting a 2 percent to 5 percent increase in attendance this year, DiGiammarco says, adding that she would characterize that estimate as "very conservative."

As its attendance is growing, the theme park is expanding as well. Silverwood plans to spend more than $2.3 million this year on new attractions, including $1.9 million to build a 72-foot-tall water slide, which Hayden-based specialty thrill-ride contractor Rocky Mountain Construction Group Inc. is set to begin installing this week. Named Ricochet Rapids, the slide should be completed by June 17, says DiGiammarco.

While Silverwood doesn't disclose revenue, DiGiammarco says the park saw a "definite increase" in revenue last year.

"Which is one of the reasons we're reinvesting back into the park and our local economy by bringing new attractions this year," she adds. "We expect to see an increase in attendance again this year, and that's based on season pass sales that are up, and our group business interest is up."

Group business includes family reunions and corporate events, among other types of gatherings, she says.

"We see more people coming to our website trying to plan their vacation trips," she says.

In addition to Ricochet Rapids, other new attractions planned for this season are two family rides in the original Silverwood area, Butterflyer and Froghopper, as well as a shooting gallery. Silverwood's main park opens for the weekends in May, before going to a daily schedule in early June, while the Boulder Beach water park is scheduled to start June 4.

Fred Grubb, Rocky Mountain's president and co-owner along with his wife, Susan Dedmon, says a crew of about eight people from North Idaho, all full-time employees, will work on the new slide. Ricochet Rapids is described as a raft ride for five to six riders who will ricochet up and down the sides of a giant tube as they ride through sharp turns and drops.

"It's enclosed and open, both, in different portions of the ride," Grubb says. "It's new technology because in the middle of the ride, there's a big 30-foot diameter circular inversion that you'll go through."

The 216-acre Silverwood, located near Athol, Idaho, is entering its 24th season and has more than 65 rides, slides, shows, and attractions. It sells full-priced season passes for $139.99 and offers a VIP pass, called a Gold Pass, for $369.99 that allows the owner to bring two guests for a day.

Silverwood began its search this month to hire up to 1,200 seasonal workers for the upcoming season. That number is up by only about 10 positions from the prior season, to allow for staffing the new attractions, DiGiammarco says. The park has 78 full-time employees.

Starting in 2009, Silverwood extended its season by a month with its Scarywood transformation in the fall, when the park created two scary-themed attractions and some scare zones. The park took the fright night scare to a grander scale last year, and it was wildly popular, says DiGiammarco.

"In 2009, we spent several hundred thousand dollars on two attractions and some scare zones just to see if public would enjoy it. It was a big success," she says. "Because of that, we pumped over a million dollars into Scarywood in 2010."

This included running the roller coaster Timber Terror backwards, construction of Blood Bayou, a "huge" clown scare zone, and the transformation of the train ride as a zombie express. The impact also increased area hotel bookings and extended Silverwood's employment season, says DiGiammarco.

"This year, we'll being doing some re-theming of the (Scarywood) attractions, some changes as far as schedule and dates, to get a better flow on attendance per day, so those attending will have a better experience but hopefully not as much standing in line," she says.

Before 2009, the park closed after the last weekend in September, but now with Scarywood, Silverwood continues operation, mostly on weekends, through the end of October. Overall, Silverwood has continued adding new rides and attractions since installing the Tremors rollercoaster in 1999.

Although new attractions typically cause a spike in attendance, Silverwood wants to add the new elements this year more for guest satisfaction and less waiting times per ride, says DiGiammarco. For example, Ricochet Rapids is considered a sister slide to the theme park's existing Avalanche Mountain slide.

"The park seems to grow every year," adds DiGiammarco. "It is getting to be a true tourist destination. We see more people come from the Seattle and Portland areas and from Canada from up as far as Calgary."