A displaced segment of the Olmstead Aqueduct in Provo Canyon was boosted back into place by bulldozers Thursday as water officials were briefed on plans to permanently fix the line.
A mile-long tunnel through the mountain that would bypass an active landslide is being contemplated, but engineers reported Thursday that one more test hole needs to be completed before the feasibility and cost issues of boring a tunnel can even be approached. The cost could range anywhere from $1,000 to $2,000 a foot, said Doug Hansen, senior geologist with the engineering firm CH2M Hill.A segment of the green pipeline has been plagued for years by a slide area that causes the line to kink and buckle as the ground moves underneath it.
Dragging the slipping section back up the hill periodically has been the typical solution to the problem during the decades since Utah Power & Light built the line to carry water from Deer Creek Reservoir to the Olmstead power plant at the mouth of Provo Canyon.
But the federal government condemned the line so it could be used to carry Central Utah Project water, and CUP officials now say a permanent solution to the sliding pipeline problem must be found to make the pipe reliable.
Test results from the fourth and final test hole should be available sometime next week, then CUP officials will engage in intense discussions with the Bureau of Reclamation on how to proceed with repairs.
"We are still trying to determine whether a tunnel is feasible," said Don Christiansen, Central Utah Water Conservancy District general manager. "Then to be decided is who will collect data, and design and construct it. It is jointly recognized that problem is unresolved between the district and the Bureau of Reclamation."
Christiansen said the bureau will likely have oversight and approval of the project's design, and the conservancy district would do most of the balance of the work.
A tunneling project would take more than two years to complete, so temporary repairs on the line will continue at least that long, Christiansen said.
"The slide is very active right now," Hansen said. Recent rains caused the slide area to displace the pipeline about 6 inches.
The line is currently empty, and bulldozers were used Thursday to pull the line back into place.