Go with the flow
TRAIL — A wet winter and once-plentiful snowpack have recharged Jackson County's two reservoirs enough that both the Rogue and Applegate rivers head into summer with the first near-normal forecasted flows in three years.
The newly forged water-release strategies for Lost Creek and Applegate reservoirs boast flow levels that will help keep the Rogue high and cool for migrating chinook salmon while providing midsummer flows for river recreators and keeping Lost Creek Lake's main boat ramp operable through the summer boating season.
The plan calls for late-June releases at about 20 percent higher than last year to help migrating spring chinook, followed by July and early August releases that will be 10 percent higher than 2015, according to the U.S. Army Corps of Engineers, which operates the two dams.
Finally, the mid-August "spike" of water meant to cool off the Lower Rogue Canyon and stave off a natural disease outbreak in migrating fall chinook salmon will be 12 percent higher than last year, Corps documents show.
The wildcard on whether the releases achieve their wild salmon-survival goals depends upon whether the runoff, forecast to be 96 percent of average upstream of Lost Creek, materializes in the reservoir or sees losses sinking into the water table parched from three years of drought.
"I'm cautiously optimistic," says Pete Samarin, the Oregon Department of Fish and Wildlife biologist who helps craft the flow strategy. "We just don't know how that water table is going to react."
ODFW biologists and state water-resources officials set the summer release schedule for how the Corps spills the 180,000 acre-feet of reservoir water set aside specifically for Rogue fisheries, which are the main driver for summer releases. Upstream recreation benefits are considered secondary, and access to the reservoir's boat ramps takes a back seat to salmon and steelhead needs.
Biologists over time have developed a systematic water-release strategy that treats Lost Creek Lake water like a savings account, spending that water when needed most, first in June for spring chinook and then in August and early September for fall chinook.
Periods such as July and early August are lulls between the needs of the two chinook runs, and releases are kept low but still higher than natural flows at those times. This year, however, more water will be released during those periods than during the past three drought years.
That news is being greeted positively by river recreators and the businesses that cater to them, such as the Grants Pass-based Hellgate Jetboat Excursions, whose large powerboats had to reduce riders to be able to negotiate some rapids downstream of the city throughout summer 2015.
"It's really a vast improvement over last year," says Travis Hamlyn, the company's general manager. "I think ODFW and the Corps have done a great job at protecting fish but still keep those water levels up for recreators. The recreational jetboaters are going to like this, too."
Last year's July flows were held at 1,500 cfs to keep as much water available as possible for later upstream migration of fall chinook. This year's strategy calls for releases of 1,650 cfs at that time.
Hamlyn says how much natural tributary flow adds to that release will determine whether Hellgate will have to do some weight-adjustments on its boats.
"It's still going to be a little skinny in July and August," Hamlyn says.
Lost Creek Lake boaters also will have it much better off this year than last year.
The lake elevation heading into the Memorial Day weekend was 32 feet higher than the unofficial start of the boating season last year, says Jim Buck, the Corps' Rogue Basin operations manager.
Last year, water levels dropped enough that the marina ramp at Stewart State Park was inoperable Aug. 11, and the water dropped another 21 feet by the time Labor Day rolled around, according to Corps graphs.
The current water-release plan calls for the ramp tip at Stewart to be under more than 7 feet of water, the graphs show.
It's even more dramatic at Applegate Lake, which didn't fill last year but officially did May 8 this year, Buck says. That reservoir entered Memorial Day weekend 37 feet higher than the same time last year, he says.
In 2015, the ODFW requested that the Corps dip 70,000 acre-feet into Lost Creek Lake's carryover storage. That storage was recovered, allowing for a more normal water-release plan this year that likely won't include any carryover water this year, Samarin says.