Sometimes it's where the rain falls
Another winter storm forecast to move into Southern Oregon Wednesday doesn't look to pack nearly the punch as last weekend's storm, which barely kept the Rogue River within its banks Sunday with virtually no assistance from flood-control dams.
The Rogue at Highway 234's Dodge Bridge near Eagle Point is forecast to begin rising again late Wednesday, with peak runoff coming early Friday at around 7,200 cubic feet per second — well short of flood stage, according to the federal Natural Resources Conservation Service.
The Rogue can flow at 20,000 cfs and still be under flood stage at Dodge Bridge.
"It doesn't look like it's going to be as strong as last weekend, at least for now," says Alan Donner, a U.S. Army Corps of Engineers hydrologist who regulates Lost Creek and Applegate dams in the Rogue Basin.
But forecasters last week called for rain and snow levels far beneath what actually hit the Rogue Basin, and the way the storm hit left Corps managers virtual bystanders.
Normally, the Corps will dial Lost Creek Lake outflows up and down during a storm to keep the Rogue about a foot below flood stage at Dodge Bridge.
Flows into the basin's largest reservoir didn't eclipse 7,200 cfs last weekend, but intense flows from tributaries Big Butte and Little Butte creeks downstream sent the Rogue skyrocketing to within a few inches of flood stage at Dodge Bridge and at the former Gold Ray Dam site near Gold Hill.
"It came up very fast," Donner says. "It was pretty impressive rises that we didn't see in the forecast."
There was nothing the Corps could do about it.
Outflows from Lost Creek Lake already were shaved back to a skinny 800 cfs as hydrologists worked to capture as much runoff into the reservoir as possible to replace 65,000 acre-feet of carryover storage released last summer to protect migrating chinook salmon amid record-low stream levels.
All the Corps could do was dial Lost Creek Lake outflows to the bare minimum of 500 cfs Sunday, Donner says.
Last weekend's storm was almost the opposite of the storm that hit Dec. 22 last year, when the majority of the runoff occurred upstream of Lost Creek Lake, Corps records show. That storm saw Lost Creek Lake inflows spike at more than 23,000 cfs, second only to the New Year's Day flood of 1997 in the reservoir's 38-year history, records show.
Last weekend's storm created localized flooding in places such as the Lazy Acres RV Park near Gold Hill and along Little Butte Creek in Eagle Point.
The Rogue eclipsed flood stage briefly Sunday in the town of Agness about 27 river miles from the Pacific.