By Laura Zuckerman
SALMON, Idaho (Reuters) - Dangerous, high-water conditions in many popular rivers and streams of the Northern Rockies are prompting scores of anglers and rafters to cancel outings to a region where summer recreation drives the economy.
Heavy rains and runoff from record mountain snows have pushed flows on trout streams favored by fishermen and rivers prized by boaters for world-class rapids to levels considered hazardous even for the extreme sportsman.
High water, blamed for the deaths in recent weeks of at least six people in Idaho, Montana and Wyoming, may worsen over the July 4 holiday weekend, the traditional launch of the region's whitewater rafting and fly-fishing seasons.
The blow to boating and fishing comes as snow, mudslides and washed-out roads have blocked access to many choice mountain lakes and campgrounds in the Rockies.
In central Idaho, an international whitewater destination, rafting and fishing guides have scrapped trips on scenic rivers such as the Salmon that have been booked a year in advance.
"This has been one of the worst Junes, if not the worst June, we've ever experienced, and all the outfitters are in the same boat," said Jess Baugh, an 18-year outfitter in Idaho near Hell's Canyon, the deepest gorge in North America.
Baugh said rising, swift-flowing and icy waters are especially unsafe for children, the chief cause for cancellations among families.
U.S. Forest Service managers of the Middle Fork Salmon River in the Frank Church River of No Return Wilderness are reporting a plunge in the number of launches on an Idaho waterway famed for its granite-walled canyons, endless rapids, sandy beaches and views of forested peaks.
With flows on some launch dates in the high-hazard range, veteran guides of the remote river have scrambled to reschedule trips by raft, kayak and drift boat.
The multi-day trips in motorless boats are seasonally regulated by a government lottery and limited in number to preserve the wilderness experience. The vacation packages cost thousands of dollars, with their value to local economies estimated in the tens of millions.
"We're not going to get on there until things moderate," said Bill Bernt, a guide on the Middle Fork Salmon for more than 40 years.
High water, which can carry large debris such as whole trees and carve new rapids, was behind the June 16 drowning death in the Middle Fork Salmon of an experienced whitewater rafter.
In Montana, sediment-shifting high flows have muddied the waters of trout streams, where clarity is needed for fly-fishing excursions that should be in full swing.
Denny Gignoux, manager of Glacier Guides and Montana Raft Co., said trips to such premier fisheries as the Smith and Middle Fork Flathead rivers will be delayed for weeks because of weather-related circumstances.
"It's just not fun fishing," he said.
Gignoux said a years-long drought that preceded this season's deluge had previously spawned worries about the impact on cold-water fish of low, warming water.
The Independence Day holiday has traditionally lured thousands to the North Platte River in southeast Wyoming for rafting and fishing, but the danger posed this year by big water is expected to thin those crowds.
"Really high runoff in some places is making fishing pretty much impossible on a lot of stretches of the river," said Eric Keszler, spokesman for the Wyoming Game and Fish Department.
(Editing by Steve Gorman and Greg McCune)