Designed to mimic the most exciting rapids in the world, the artificial river being constructed as part of the U.S. National Whitewater Center in Charlotte, NC, will be the future site of the official U.S. Olympic team training center for the U.S.A. canoe and kayak teams.
According to Director of Development Lance Kinerk, the $35-million Whitewater Center, which sits on 306-acres, will include a conference center, restaurant, parking, high ropes course, mountain bike trails, rock climbing, and a 49-acre rafting attraction.
“The designer of the river attraction is Scott Shipley, an Olympic kayaker, who based the water system on his favorite rapids from around the world,” Kinerk said. “This will be the first of its kind in the United States.”
The lead designer of the entire center is Michael Williams, of Liquid Design in Charlotte, NC.
The two prime contractors are Rodgers Builders and R.T. Dooley Construction Company, both of Charlotte, NC.
Kinerk said the man-made river will be .75 mi. long with an upper and lower pond and four courses named competition, big water, freestyle and wilderness — each with its own unique rapids.
“Two channels flow from the upper pond of the water system, then one channel splits, coming back together before flowing into a three acre lower pond,” Kinerk said.
Three types of obstructions provide varying degrees of rapids within each of the channels.
“Two movable obstacles in the man-made river will allow configurations of rapids to be changed,” Kinerk said. “These include omni floats placed on a pegboard type system and flippers on a pinball type system capable of creating between three- and seven-foot waves.
“A third obstacle will remain stationary and includes natural rocks and boulders.”
Rock work at the Center began in early February.
Colorado-based Burough Construction is responsible for all the natural rockwork and placement, and acts as an advisor to the design engineers. Burough employs seven people and specializes in river restoration, whitewater parks and boulder handling projects.
“The company is building drop structures that will be anchored with high bounding grout and rebar pins to the concrete liner,” Burough said. “The boulders will be placed to create a natural drop in the flow of water, which produces waves. The boulders will also direct the water in the direction of the next obstacle on the water course.”
He said the most demanding aspect of this job has been building the drop structures so that they won’t dislodge from the force of the water flow.
“The water pumps are capable of filling an Olympic-size pool in eight seconds. That’s a tremendous amount of water pressure,” Burough said.
The collection of rocks for this project began three years ago.
“The granite rocks, ranging in size from two to 10 tons, all came from North Carolina roadwork and other construction sites. Some rocks were donated, while others had to be purchased, Borough said.
Two-thirds of the rocks are on site, while the remainder are being stored at an off-site location.
“Rocks are transported in a 38-ft. half round Clement trailer pulled by a 2000 International truck,” said Burough. “The rocks are so large that often we can only transport three at a time.”
The rocks are set into place with a John Deere 270 CLC excavator and 100-ton crane. Also on site are 5-yd. John Deere loaders, which move the rocks from the stock pile to the staging area.
“This is a unique project for us, because it is the first man-made system we have worked on. Working in a man-made system is more difficult than working in a natural setting,” Burough said. “It is a tremendous challenge to set the boulders on a concrete slab, with no foundation, so that they won’t slide down the river from the force of the water flow.”
When working in a natural river, the firm builds cofferdams to channel the water away from the working area during construction.
Work Began in Spring 2005
According to Scott Carr, senior project manager of Rodgers Builders, on-site preparations for the center began in March 2005.
“Preparation work included clearing the area of forest and excavating 300,000 cu. yds. of dirt that was cut and filled on site to construct the channels,” Carr said. “Showalter Construction of Charlotte, NC, supplied the equipment and was responsible for all the excavation and grading. Concrete work will all be done by Rodgers Construction.”
The steep slope of the channel’s walls created a challenge during the concrete work.
“Placement and finishing of the concrete was difficult because of the 3:2 slope of the channel,” Carr said. “The construction crew created a piece of equipment, utilizing a fork lift and adding extended steel arms, that could screed the concrete smoothly in sweeping curves to create the channel walls. Workers named it ’The Castle,’ after its inventor, Project Superintendent Mark Cassel.”
According to Cassel, prior to pouring the concrete, a strux fiber was placed on the bottom of the channel, which prevents the concrete from cracking and the water from leaking.
“The concrete was placed on the slopes using concrete pumps with booms capable of reaching 130 feet,” Cassel explained. “The Castle then screeds and vibrates the concrete to the slope. The vibrations keeps the concrete compact when it hits the slope. The final step is to manually finish with a concrete light broom.”
Approximately 12,000 cu. yds. of concrete was used for the 6-in. concrete liner of the channel.
Carr said a 4000-psi additive was added to the low slump concrete (which contains minimal water) so that the concrete would stick better to the slopes.
Moving the Water
Pumps will push water from the lower pond to the upper pond.
Seven pumps will move 537,000 gal. of water per minute from the lower pond, up the 25 ft. to the upper pond. Then, gravity will pull the water down forming rapids.
According to Carr, Rodgers Builders will install the Sweden ITT flight 750-hp pumps while Starr Electric, of Charlotte, NC, will be responsible for the wiring.
Creative Financing Moved
The financing for the Whitewater rafting attraction involved convincing backers of Mecklenburg County, Charlotte and several Gaston County governments to guarantee their bank loans. If the project makes money as expected, local officials won’t be responsible for any debt. The business plan estimates at least 177,000 people will raft the center’s rapids each year. If the number of rafters paying to use the facility drops below 100,000, the center will fail to cover its expenses.
The river and mountain bike trails will be open June 15. The rest of the attractions will open in phases.
On most days the Center’s water attraction will be open to visitors for rafting, canoeing and kayaking. However, several times a year, organizers expect to host Olympic trials, World Cup events and other competitions.
For more information, visit www.usnwc.org. CEG