‘Herculean’ effort to rebuild RVID canal
Jun 20, 2017 – By Daniel Bendtsen, Staff Writer
Crews are on their way to completing a rebuild of the Riverton Valley Irrigation District canal.
The work must take place in order to restore water access to roughly 50 family farms before crops are lost.
Joe Crofts, who runs a farm on the RVID ditch, gave permission to the district Sunday night to have a re-routed section of canal run through his private property, bypassing a 300-foot section where stream flows had blown out the canal’s south bank and returned to the main channel during record-setting flooding on the Wind River a week prior.
Crofts granted the easement without receiving compensation.
Army Corps of Engineers
On Monday morning, a surveyor from North State Environmental charted a route for the new canal. After receiving approval from the Army Corps of Engineers by the afternoon the North State Environmental team began digging a 1,250-foot section of canal using two Caterpillar D10 bulldozers and three track hoes — all of which had been shipped in over the weekend.
“I can’t believe we got all this equipment this fast,” NSE project manager Shane Trotter said Monday morning. “It just worked out perfect.” Working 20 hours per day, crews had excavated several hundred feet of the canal by mid-day Tuesday.
Trotter said the new canal would require the removal of about 20,000 yards of material.
Meanwhile, water continues to run unfettered around the ditches’ head gate and a half mile downstream to the blown-out section.
If the new canal section is completed before the head gate is secured, the new canal section could still be connected, restoring water access to 8,500 acres downstream.
If that ultimately becomes possible, some water access could be restored by the end of this week.
However, the canal is only designed to hold 150 cubic feet of water, and deciding whether to breach into the new canal section could depend on how much the river’s stream flow has fallen by the time of completion.
The rebuild was expected to take three to four days, beginning Monday.
“If they can at least restore access to the row crops, there would be a lot of thankful farmers,” said Steve Doyle, who relies on Riverton Valley to irrigate his crops.
On Tuesday afternoon, the Wind River near Kinnear had roughly 8,500 cubic feet per second of water flowing. High temperatures are expected to keep the stream flow at above 8,000 cfs until at least Friday.
When the Wind River swung north June 9, well out of its established channel, it ran around Riverton Valley’s head gate, forcing 1,200 cfs of water into the canal designed to hold one-eighth that amount.
By Thursday, the river had annexed much of the land around the canal, and a lengthy stretch of water stood between the head gate and dry land accessible by Quartz Drive, the nearest access point.
Driving down Quartz Road, 10 belly dump tractor-trailers each were filled with 25 tons of gravel before crossing over the canal on a rickety wooden trestle bridge and continuing on a two-track road toward six dump trucks.
In what local Doyle called a “Herculean effort,” the crews fought against the current, dumping truckload after truckload of gravel into the water in an attempt to reach the head gate.
Dike and road
Work continued through Fathers Day. By Sunday night, crews had brought in roughly 7,400 tons of gravel, reaching the head gate and beginning to construct a 1,400-foot dike to force water back into the main channel.
Doyle said the crews were completing roughly 300 feet of dike on Thursday, Friday and Saturday while constantly repairing the road.
“They have to get these big trucks through there, and they’re continuously destroying the road that they just built,” he said. “They’ve been putting in quite a bit of fill just to keep the road maintained.”
Despite the effort, Mother Nature wasn’t kind.
Heavy rain near Dubois on Friday night led to a sudden surge in the Wind River. Equipment and supplies were moved to higher ground Sunday to wait out the flood.
Crews feared the river might wash out the bridge they relied on to cross over the canal and, in preparation, intentionally breached a section of the road they had just built.
The plan didn’t work.
The stream flow Monday at Riverton came within 90 cfs of breaking the record of 12,060 cfs that was set just nine days prior. By that morning, the bridge was broken down and underwater.
The river also washed out much of the newly constructed dike, as well as several sections of the newly constructed roadway. Meanwhile, the increased flow east of town flooded the local gravel pit, making it impossible for crews to load or deliver gravel. Work stopped while Wayne Neil, the district’s manager, searched for a portable replacement bridge Monday.
By Tuesday afternoon, the crews were building a new bridge and hoping water would begin receding so construction could continue.
Once water access is restored, Riverton Valley will begin to repair roads, clean up debris and fix other damaged infrastructure, including weirs and bridges, Neil said.
At this point, the district is absorbing all costs for construction with the anticipation that there will be reimbursement through federal funding.
Riverton Valley’s board of directors has been meeting with First Interstate Bank officials to secure an emergency loan.