More than a million visitors have ridden the chair lifts at the famous Whistler resort in British Columbia. That figure doesn't count skiers or snowboarders; it's just the number of mountain bikers there.
The brisk business at Whistler Mountain Bike Park has inspired ski areas from Stevens Pass in Washington to Mount Bachelor in Oregon to build their own summer bike parks.
But some environmental groups say mountain biking isn't an appropriate activity in alpine meadows -- a contention that's playing out on Oregon's Mount Hood.
The mountain's Timberline Lodge boasts that it's one of the only ski resorts in the U.S. that's open through the summer, thanks to its Palmer Lift, which shuttles skiers up a glacier at about 8,000 feet. Now Timberline hopes to attract a summer visitors interested in carving a different kind of turn.
Proposed trails map
Last year, after much debate, the U.S. Forest Service approved a proposal from RLK and Company, the managers of Timberline, to build 17 miles of new mountain bike trails on several ski slopes. Steve Kruse, who manages Timberline's mountain operations, says the bike park will be a natural fit for the adrenaline seekers, tourists, and local families who flock to the mountain.
"It's addictive. It's extremely fun," Kruse says.
The park at Timberline would be designed for beginner and intermediate flow riding. Kruse describes the flow style as something "close to a roller coaster ride. The design of the trails themselves control the pace of the rider. There's adventure when you go down a little swoop. We build in features to slow people down."
At the bottom, a modified chair lift with a bike rack will be waiting to take you back up the hill. Kruse says Timberline doesn't expect to make a huge amount of money from the park -- less than $380,000 a year. But running it would create about 20 new jobs for summer lift operators and a trail crew.
"We're going to be able to take people who are used to being seasonal and turn them into full time, and keep around good quality people," he says.
In fact, President Barack Obama signed a bill into law in 2011 that encourages this kind of summer development at ski areas as way to create jobs.
Kruse had planned to break ground on the trails this summer. But four environmental groups have sued to block the project. They include the Sierra Club and the Mount Hood watchdog group Bark. So what's their concern about bike trails?
"The sediment, and the impacts on the aquatic system," according to Russ Plaeger. He's with the environmental advocacy group Bark. Plaeger voiced those concerns while standing on the banks of a cold, clear stream that tumbles down the mountain spitting distance from the Jeff Flood Chair Lift -- right where the proposed bike park would go.
"Still Creek, where we're standing now — this is critical habitat for winter steelhead. Which means it's very important to the survival of that species," Plaeger says.
Plaeger says several miles downstream from here, Still Creek is also a key spawning ground for spring chinook salmon. Development in the ski area and the practice of sanding nearby roads has choked parts of Still Creek with sand and fine sediment, which can be deadly to salmonid eggs and fry. Plaeger believes that the planned mountain bike trails will cause further erosion, and undermine the effort to restore wild salmon populations on Mount Hood.
But Timberline's Kruse says the trails will be engineered and maintained to avoid triggering erosion. That's one of the reasons the Forest Service approved the new trails in the first place.
"They're designed to stop water from running. They're designed to be their own drainage systems. They're designed to be their own sediment traps."
Timberline also says it will remove several miles of old roads and plant new vegetation to offset any erosion caused by the bike park. But environmental groups counter that in alpine meadows, restoration is easy to promise and hard to deliver. Jon Rhodes, a hydrologist who is helping with the lawsuit, says Timberline's attempts to restore disturbed ski-slopes have failed in the past.
"The soils are not very productive. They don't grow vegetation very easily, especially once disturbed. The growing season is very short. It's very cold. And vegetation doesn't grow quickly."
Proponents of the bike park point out that the south side of Mount Hood, where Timberline sits, is a designated recreation area, a place that President Franklin Delano Roosevelt himself envisioned in a dedication speech as a center for summer sports and winter play. They argue that it makes sense to concentrate development in an area already impacted by heavy winter use.
Some in Portland's mountain biking community feel the environmental groups' lawsuit is driven in part by a stereotype that mountain bikers are thrill-seekers who don't appreciate the environment.
"It comes from fear. Fear from the unknown. And I think in reality, mountain bikers are just like hikers and just like equestrians who want to go out and convene with nature. And I think that having a mountain bike park at Timberline would make that more accessible for more people," says Barry O'Conner, a manager at Fat Tire Farm, a mountain bike specialty shop in Portland.
Bark's Plaeger acknowledges that part of what he and others at Bark object to is the speed and noise of the bikes.