Unseasonably cool temperatures and sprinkling rain provided the perfect environment Friday for Randy Christianson to make his point.

"We should be open right now, having fun," he said. "But it's 50 degrees out."

The owner of Mandan's Raging Rivers Water Park has had to battle the weather in each of his five summers of operation. It's time, he said, to take Mother Nature out of the equation.

Christianson unveiled plans Friday for a major addition to Raging Rivers that will include a massive indoor water park and a 90-room hotel.

"The industry is going to indoor parks," he said. "It takes the No. 1 enemy of water parks - the weather - out."

If all goes according to plan, the new complex could be completed by 2008. Funding is about 90 percent secure right now, he said.

Christianson has been working on the idea for the indoor-outdoor complex for nearly three years, he said. The $25 million addition would include a 52,000-square-foot indoor water park, which would include a retractable glass roof. Part of the sides of the enclosure could be lifted, too, to allow sunshine and warm weather to enter the complex.

The plan also calls for a 22,000-square-foot enclosed retail area, where Christianson envisions putting a food court, arcade, indoor mini-golf course and other shops. Attached to the retail area and the indoor water park would be the hotel.

"Water parks used to be places where mom and dad would drop off the kids and come pick them up in four or five hours," Christianson said. "That's changed. Now it's become a place where the whole family wants to spend the day or the weekend. We want to offer more to mom, dad and the kids."

The addition would be located on the southwest corner of the property. The current enclosure would be removed to make way for the new structure. The current waterslides, the water play area, the go-cart tracks and the mini-golf course will remain unchanged.

The indoor water park will include three new tube slides and a 120-foot-wide wave pool that will be incorporated into a 500-foot-long "lazy river." The river will be connected to the existing lazy river, so guests can float inside, outside or both. Part of the river, Christianson said, will pass through a bar area where adults can pull over for a cocktail.

Eventually, a full-menu restaurant will be added to the south side of the retail area, he said.

An indoor roller-coaster will run throughout the new complex.

Christianson said he needs to make Raging Rivers a year-round operation, and he said this addition will allow him to do that. When asked about Canad Inn's proposed water park near the Bismarck Civic Center, Christianson said he wouldn't mind the competition, as long as the company is financing all of its own project.

"Cities should not be involved in any venture where there is private enterprise," he said, "especially if it is going to give the competition a competitive edge by utilizing city facilities."

Canad Inns last month presented a proposal to a city advisory group to build a 16-story hotel and water park adjacent to the Civic Center.

The company's proposal was contingent upon the city completing its master plan for the Civic Center, which includes a 20,000-square-foot addition for a banquet hall and offices. The price tag for that addition was estimated to be between $12 million and $15 million.

Christianson has been in the entertainment business for more than 10 years. He and a California-based partner have invested more than $5 million into Raging Rivers but have averaged just about 50 days of business each summer.

"The weather here is so hit and miss,"he said. "We need to do the indoor water park and hotel to get the return we need on our money."

Christianson said the project is waiting on final environmental approval and the last bit of funding.

(Reach reporter Tony Spilde at 250-8260 or tony.spilde@;bismarcktribune.com.)