The Matanuska River, swollen with a surge of snowmelt brought on by 70 degree temperatures this week, is carving up riverbanks and threatening property from Sutton to the Butte.
The braided glacial river's high water comes in July or August, as predictably as fireweed blossoming or salmon running.
But this year it's thundering at 20,000 cubic feet per second just as summer is officially beginning, according to the Mat-Su Borough.
"It's a month early," said Patty Sullivan, a borough spokeswoman.
People who use the river for recreation are being advised to stay off of it, Sullivan said.
Water levels are high because a string of balmy days and rain combined to unlock heavy winter snow lingering in the mountains, said National Weather Service river hydrologist Ben Balk.
The highest reading of the Matanuska River in recent days, taken at the Old Glenn Highway near Palmer, peaked at 9.85 feet, Balk said. Flood stage, when the river goes over its bank, is 12 feet, he said.
"From our standpoint it's not necessarily a flood threat," Balk said. "It's an erosion threat."
In Butte, the concern is flooding. The fire chief knocked on doors there Tuesday night, warning around a dozen homeowners near Ye Old River Road about the possibility, Sullivan said. About 1,000 sandbags are available for residents to pick up at the Butte Fire Station.
So far, water hasn't flowed into the developed area of the road, Sullivan said.
On Thursday, there were reports of standing water on Maud Road near the river. A bike path that parallels the Old Glenn Highway had been closed.
In Chickaloon, Nova River Runners has canceled rafting trips at a peak time in their season -- not only on the Matanuska River but on other rivers like the Chickaloon and Talkeetna too. The water is just too high and moving too fast, said owner Chuck Spaulding.
"It's like the perfect storm," he said. "We've got the snowpack which is not out of the norm. But it's how it's coming out. It's not quitting."
In Sutton, a homeowner lost 35 feet of land in two days, according to Sullivan.
Nancy Bertels, a librarian in Sutton, said property owners have fought erosion for decades.
A few families are again close to losing chunks of their land to the river. On one riverfront property a wood pile has almost gone, she said. On another a septic tank is close.
High water levels along with warm weather will continue into the weekend before cooler, cloudier weather moves in starting Sunday, Balk said.
At the moment, Bertels said, the river is muddy and churning and appears to be looking for a fight.
"It looks angry," she said.
Reach Michelle Theriault Boots at email@example.com or 257-4344.