TID fixes breached canal that resulted in landslide, turbidity in stream flows
APPLEGATE — Talent Irrigation District crews have completed repairs to a broken irrigation canal blamed for causing a landslide that muddied stream flows throughout the Applegate Valley over the weekend, authorities said.
Muddy water in the Applegate River was reported from its confluence with the Little Applegate River downstream past the community of Applegate, according to the state Department of Environmental Quality.
TID Manager Jim Pendleton said his crews on Monday discovered that a tree had fallen into the 1920-era earthen canal in a slide-prone area near McDonald Creek.
The branches caused the water to back up in the canal, eventually causing one side to fail, sending mud and water into McDonald Creek, which flows into the Little Applegate, Pendleton said.
"That's when we shut the whole Mary Ann down Monday," Pendleton said.
Pendleton said the canal was carrying less than 3 cubic feet per second of water — far less than the 15 cfs that flows there during the height of irrigation season.
Pendleton said he believes the canal was not responsible for all the turbidity in the water, saying earlier rain and recent snowmelt likely contributed to it, too.
However, Forest Service officials and Oregon State Police troopers searched for other causes of the weekend turbidity without success, said Bill Meyers, the DEQ's Rogue Basin coordinator.
"Nothing else has been located as a source," Meyers said.
Based on the timing of complaints from Applegate Valley residents who saw unusually dirty stream flows, the ditch likely collapsed late Friday or Saturday, Meyers said.
TID crews fixed the ditch by installing a pipe in the breached portion of the canal. Other Rogue Valley streams joined the mud party Wednesday after dirty runoff from heavy rain caused streams throughout the Rogue Basin to rise.
By Wednesday afternoon, the Rogue River was dirty from the mouth of Big Butte Creek on down, while streams such as Bear Creek rose from 200 cfs to 700 cfs overnight, records show.
"That was a pretty good rain event we experienced yesterday," Meyers said. "I'd expect things to get a little brown and dirty."
Flows out of the Rogue Valley were strong enough to set a record Wednesday at the U.S. Geological Survey gauge in the Rogue River at Agness, about 35 miles east of the Pacific Ocean.
Flows there peaked Wednesday at slightly more than 16,500 cfs, which is the highest flow ever recorded there for April 28 during the gauge's 49-year history, USGS records show.
The previous high for April 28 at Agness was about 10,400 cfs, in 1996. The average flow for late April is slightly more than 5,500 cfs.
Reach reporter Mark Freeman at 541-776-4470, or e-mail at email@example.com.