Weather Radar Gave No Clues Rivers Drop, But Expected Melt From Recent Snow Still A Worry

Flood warnings remained in effect late Friday for nine Montana counties, but most of the state’s swollen rivers seemed to be receding.

A state emergency announcement warned, however, that snowfall from recent days soon will be melting.

“It’s not over,” said Jim Anderson, operations officer at the state Disaster and Emergency Services office in Helena.

Three new $5 million weather radar systems failed to detect the approaching rainstorm, which also caused flooding near Kalispell.

Poor monitoring of rising rivers also contributed.

“We got just no warning,” said Kim Potter, Flathead County disaster and emergency services director. He had harsh words for the new weather radar systems installed in Spokane, Missoula and Great Falls.

The new systems have eliminated the night shift at the National Weather Service office in Kalispell, which is scheduled for eventual closure, so there was no one to track the storm that moved through Tuesday night.

The new radar systems were supposed to detect such storms. But the radar at Missoula is angled upward one-half of 1 degree, as are others around the nation. While that causes no harm in the flatlands, in the mountains it means the radar scans above 12,000 feet high over Kalispell and 18,000 feet high at the U.S.Canadian border. Radar in Spokane and Great Falls scan even higher by the time the signals reach Kalispell.

“This whole storm was under the 18,000-foot level,” Potter said.

The fierce early summer storm washed out a 60-foot section of the celebrated Going-to-the-Sun Road in Glacier National Park, and floodwaters took out at least 35 of the park’s 200 backcountry bridges.

The storm dumped 3 to 5 inches of rain in 24 hours in the headwaters of the North Fork of the Flathead River, and 7 inches in the Belly River drainage in the park’s northeast corner.

The deluge washed out the outside lane near the West Side Tunnel on the scenic mountain road that twists over the Continental Divide at Logan Pass and is the centerpiece attraction for the park’s summer visitors. It eroded a swath 80-100 feet down the slope, biting as deep as 15 feet into the 22-foot-wide roadway.

No one was injured in the storm and flooding.

On the Clark Fork River, Washington Water Power Co. dams are spilling 20,000 cubic feet of water each second - water that cannot be funneled through the turbines to generate electricity, spokeswoman Dana Anderson said.

Normal spring runoff peaks at 65,000 cubic feet per second, she said. Flows this week have been 70,000 feet per second. The turbines at Noxon Rapid and Cabinet Gorge dams can handle only 50,000 feet per second.

By comparison, the Spokane River spring runoff peaks at 25,000 feet per second.

Near Kalispell, flood waters subsided but nearly 20 mobile homes remained flooded early Friday.

“I can’t even get into my house,” said Sharon Elavsky, who evacuated her family early Thursday and hadn’t returned since.

Most of the estimated 100 homes in the flood area appeared to have escaped serious water damage, however. Homes were elevated on blocks and gravel pads, just inches above the high-water mark.

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